1. General description
The PCT2075 is a temperature-to-digital converter featuring 1C accuracy over 25 C
to +100 C range. It uses an on-chip band gap temperature sensor and Sigma-Delta
A-to-D conversion techniq ue with an overtemperature dete ction output that is a drop-in
replacement for othe r LM75 series thermal sensors. T he device contains a n umber of data
registers: Configuration register (Conf) to store the device settings such as device
operation mode, OS op eration mode, OS polarity and OS fault queue; temperature
register (Temp) to store the digital temp reading, set-point registers (Tos and Thyst) to
store programmable o vertem per ature shu tdown and hystere sis limits, and progra mma ble
temperature sensor sampling time T idle, that can b e communicated by a controller via the
2-wire serial I2C-bus Fast-mode Plus interface.
The PCT2075 also includes an open-drain output (OS) which becomes active when the
temperature exceeds the programmed limits. The OS output operates in either of two
selectable modes: OS comparator mode or OS interrupt mode. Its active state can be
selected as either HIGH or LOW. The fault queue that defines the number of consecutive
faults in order to activate the OS output is programmable as well as the set-point limits.
The PCT2075 can be configure d fo r different operation conditions. It can b e set in n ormal
mode to periodically monitor the ambient temperature, or in shut-down mode to minimize
power consum p tion .
The temperature register always stores an 11-bit two’s complement data, giving a
temperature resolution of 0.125 C. This high temperature resolution is particularly useful
in applications of measuring precisely the thermal drift or runaway. When the device is
accessed the conversion in process is not interrup ted (that is, the I 2C-bus section is totally
independent of the Sigma-Delta con verter section) and acce ssing the device continuou sly
without waiting at least one conversion time between communications will not prevent the
device from updating the Temp register with a new con version result. The new conversion
result is available immediately after the Temp register is updated. It is also possible to
read just one of the temperature register bytes without lock-up.
The PCT2075 powers up in the normal operation mode with the OS in comparator mode,
temperature threshold of 80 C and hysteresis of 75 C, so that it can be used as a
stand- alone thermostat with those pre-defined temperature set points. The default
set points can be modified during manufacture and ordered under custom pa rt number.
There are three selectable logic address pins with three logic states so that 27 8-pin
devices or thre e 6-pin devices can be connected on the same bus withou t address
conflict.
PCT2075
I2C-bus Fm+, 1 C accuracy, digital temperature sensor and
thermal watchdog
Rev. 10 — 20 November 2017 Product data sheet
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Product data sheet Rev. 10 — 20 November 2017 2 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
2. Features and benefits
Pin-for-pin replacement for LM75 series but allows up to 27 devices on the bus
Power supply rang e from 2.7 V to 5.5 V
Temperatures range from 55 C to +125 C
Frequency rang e 20 kHz to 1 MHz with SMBus time-ou t to prevent h anging up the bu s
1 MHz Fast-mode Plus 30 mA SDA drive allows more devices on the same bus but is
backward comp atible to Fast-mode and Standard-mode
11-bit ADC that offers a temperature resolution of 0.125 C
Temperature accuracy of:
1C (max.) from 25 C to +100 C
2C (max.) from 55 C to +125 C
Programmable temperature threshold and hysteresis set points during operation
Supply current of <1.0 A in shut-down mode for power conservation
Stand-alone operation as thermostat at power-up
ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per
JESD22-C101
Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
Small 8-pin package types: SO8, TSSOP8 and 2 mm 3mmHWSON8
Small 6-pin package type: TSOP6
3. Applications
System therma l ma na ge m en t
Personal comput er s
Electronics equipment
Industrial controllers
Cooling system: turn on when the temperature is higher (hotter) than -5C; turn off
when the temperature is below -10C
Fig 1. Cooling system using custom part PCT2075GV/N005
aaa-027129
-5°C T
ots
OS reset
OS active
AC off
-10°C T
hys
AC on
AC off
reading temperature limits
AC on
OS output in comparator mode
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Product data sheet Rev. 10 — 20 November 2017 3 of 37
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
4. Ordering information
[1] ‘x’ changes depending on the assembly work week 1 through 5
[2] PCT2075GV/N005 is a custom part with Tos = 5C and Thyst = 10 C
[3] PCT2075GV/P110 is a custom part with Tos = 110 C and Thyst = 105 C
4.1 Ordering options
Table 1. Ordering information
Type number Topside
mark Package
Name Description Version
PCT2075D PCT2075 SO8 plastic small outline package; 8 leads; body width 3.9 mm SOT96-1
PCT2075DP P2075 TSSOP8 plastic thin shrink small outline package; 8 leads;
body width 3 mm SOT505-1
PCT2075TP 075 HWSON8 plastic thermal enhanced very very thin small outline
package; no leads; 8 terminals, 2 30.8 mm SOT1069-2
PCT2075GV 20x[1] TSOP6 plastic thin small outline package; 6 leads SOT1353-1
PCT2075GV/N005[2] 05x[1] TSOP6 plastic thin small outline package; 6 leads SOT1353-1
PCT2075GV/P110[3] 10x[1] TSOP6 plastic thin small outline package; 6 leads SOT1353-1
Table 2. Ordering options
Type number Orderable
part number Package Packing method Minimum
order
quantity
Temperature
PCT2075D PCT2075D,118 SO8 Reel 13” Q1/T1
*standard mark SMD 2500 Tamb =55 C to +125 C
PCT2075DP PCT2075DP,118 TSSOP8 Reel 13” Q1/T1
*standard mark SMD 2500 Tamb =55 C to +125 C
PCT2075TP PCT2075TP,1 47 HWSON8 Reel 7” Q2/T3
*standard mark 4000 Tamb =55 C to +125 C
PCT2075GV PCT2075GVJ TSOP6 Reel 13” Q1/T1
*standard mark SMD 5000 Tamb =55 C to +125 C
PCT2075GV PCT2075GVX TSOP6 Reel 7” Q1/T1
*standard mark SMD 3000 Tamb =55 C to +125 C
PCT2075GV/N005 PCT2075GV/N005X TSOP6 Reel 7” Q1/T1
*standard mark SMD 3000 Tamb =55 C to +125 C
PCT2075GV/P110 PCT2075GV/P110X TSOP6 Reel 7” Q1/T1
*standard mark SMD 3000 Tamb =55 C to +125 C
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Product data sheet Rev. 10 — 20 November 2017 4 of 37
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
5. Block diagram
6. Pinning information
6.1 Pinning
Fig 2. Block diagram of PCT2075
PCT2075
SDA
VCC
SCLA0
OS
A1 GNDA2
002aag634
BIAS
REFERENCE
BAND GAP
TEMP SENSOR
OSCILLATOR
POWER-ON
RESET
11-BIT
SIGMA-DELTA
A-to-D
CONVERTER
POINTER
REGISTER
TIDLE/TIMER
COMPARATOR/
INTERRUPT
COUNTER
LOGIC CONTROL AND INTERFACE
CONFIGURATION
REGISTER
THYST
REGISTER
TOS
REGISTER
TEMPERATURE
REGISTER
Fig 3. Pin configuration for SO8 Fig 4. Pin configuration for TSSOP8
Fig 5. Pin configuration for HWSON8 Fig 6. Pin configuration for TSOP6
PCT2075D
SDA V
CC
SCL A0
OS A1
GND A2
002aag635
1
2
3
4
6
5
8
7
PCT2075DP
SDA VCC
SCL A0
OS A1
GND A2
002aag636
1
2
3
4
6
5
8
7
002aag637
terminal 1
index area
1SDA
PCT2075TP
Transparent top view
2SCL
3OS
4
8
7
6
5GND
VCC
A0
A1
A2
PCT2075GV
A0 SDA
GND
VCC SCL
002aag638
1
2
3
6
OS
5
4
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Product data sheet Rev. 10 — 20 November 2017 5 of 37
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
6.2 Pin description
[1] HWSON8 package die supply ground is connected to both the GND pin and the exposed center pad. The
GND pin must be connected to supply ground for proper device operation. For enhanced thermal,
electrical, and board-level performance, the exposed pad should be soldered to the board using a
corresponding thermal pad on the board, and for proper head conduction through the board thermal vias
need to be incorporated in the PCB in the thermal pad region.
Table 3. Pin description for SO8, TSSOP8 and HWSON8
Symbol Pin Description
SDA 1 Digital I/O. I2C-bus serial bidirectional data line; open-drain.
SCL 2 Digital input. I2C-bus serial clock input.
OS 3 Overtemp Shutdown output; open-drain.
GND 4[1] Ground. To be connected to the system ground.
A2 5 Digital input. User-defined address bit 2.
A1 6 Digital input. User-defined address bit 1.
A0 7 Digital input. User-defined address bit 0.
VCC 8 Power supply.
Table 4. Pin description for TSOP6
Symbol Pin Description
A0 1 Digital input. User-defined address bit 0.
GND 2 Ground. To be connected to the system ground.
VCC 3 Power supply.
SCL 4 Digital input. I2C-bus serial clock input.
OS 5 Overtemp Shutdown output; open-drain.
SDA 6 Digital I/O. I2C-bus serial bidirectional data line; open-drain.
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7. Functional description
7.1 General operation
The PCT2075 uses the on-ch ip band gap sensor to measure the device temperatur e with
the resolution of 0.125 C and stores the 11-bit two’s complement digital data, resulted
from 11-bit A-to-D conversion, into the device Temp register. This Temp register can be
read at any time b y a con t roller on the I 2C-b us. Read ing tempe ratu re data does not affect
the conversion in progress during the read ope ration.
The PCT2075 can be set to operate in either mode: normal or shutdown. In normal
operation mode, the temp-to-digital conversion is executed every 100 ms or other
programmed value and the Temp register is updated at the end of each conversion.
During each ‘conversion period’ (Tconv) of about 100 ms, the device takes only about
28 ms, called ‘temperature conversion time’ (tconv(T)), to complete a temperatur e-to-data
conversion and then becomes idle for the time remaining in the period. This feature is
implemented to significantly reduce the device power dissipatio n.
In shutdown mode, the device becomes idle, data conversion is disabled and the Temp
register holds the latest result; however, the device I2C-bus interface is still active and
register write/read ope ration can be performe d. The device opera tion mode is controllable
by programming bit B0 of the configuration register. The temperature conversion is
initiated when the device is powered-up or put back into normal mode from shutdown.
In addition, at the end of each conv ersion in normal mode, the temperatur e data (or Temp)
in the Temp register is automatically compared with the overtemperatur e shutdown
threshold data (or Tots) stored in the Tos register, and the hysteresis data (or Thys) stored
in the Thyst register, in order to set the state of the device OS output accordingly. The
device Tos and Thyst registers are write/read capable, and both operate with 9-bit
two’s complement digital data. To match with this 9-bit operation, the Temp register uses
only the 9 MSB bits of its 11-bit data for the comparison. Tots must always be higher than
Thys.
The way that the OS output responds to the comparison operation depends upon the OS
operation mode selected by configur ation bit B1, and the user-defined fault que ue defined
by configuration bits B3 and B4.
In OS comparator mode, the OS output behaves like a thermosta t. It becomes active
when the Temp exceeds the Tots, and is reset when the Temp drops below the Thys.
Reading the device registers or putting the device into shutdown does not change the
state of the OS ou tput. The OS output in this case can be used to control cooling fans or
thermal switches.
In OS interrupt mode, the OS ou tp ut is used for thermal interruption. When the device is
powered-up, the OS output is first activated only when the Temp exceeds the Tots, then it
remains active indefinitely until being reset by a read of any register. Once the OS output
has been activated by crossing Tots and then reset, it can be activated again only when
the Temp drops below the Thys; then again, it remains active indefinitely until being reset
by a read of any register . The OS inte rrupt operation would be continued in thi s sequence:
Tots trip, Reset, Thys trip, Reset, Tots trip, Reset, Thys trip, Reset, etc. Putting the device
into the shut down mode by se tting the bit 0 of the configuration register al so resets the OS
output.
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
In both cases, comparator mode and interrupt mode, the OS output is activated only if a
number of consecutive faults, defined by the device fault queue, has been met. The fault
queue is programmable and stored in the two bits, B3 and B4, of the Configuration
register. Also, the OS output active state is selectable as HIGH or LOW by setting
accordingly the configuration register bit B2.
At power-up, the PCT2075 is put into normal operation mode in OS compa rator mode, the
Tots is set to 80 C, the Thys is set to 75 C, the OS active state is selected LOW and the
fault queue is equal to 1. The temp reading data is 0 C and not updated until the first
conversion is completed in about 28 ms. The default Tots and Thys is set at th e factory an d
can be modified on custom part number.
The OS response to the temperature is illustrated in Figure 7.
7.2 I2C-bus serial interface
The device can be connected to a compatible 2-wire serial interface Fast-mode Plus
I2C-bus as a slave device under the control of a controller or master devic e, us ing tw o
device terminals, SCL and SDA. The controller must provide the SCL clock signal and
write/read data to/from the device through the SDA terminal. Notice that if the I2C-bus
common pull-up resistors have not been inst alled as required for I2C-bus, then an external
pull-up resisto r, about 1.5 k, is needed for each of these two terminals. The bus
communication protocols are described in Section 7.10.
(1) OS is reset by either reading register or putting the device in shutdown mode. It is assumed that
the fault queue is met at each Tots and Thys crossing point.
Fig 7. OS response to temperature
002aah455
(1) (1) (1)
Tots
Thys
OS reset
OS active
OS reset
OS active
OS output in comparator mode
OS output in interrupt mode
reading temperature limits
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.2.1 Bus fault time-out
If the SDA line is held LOW for longer than tto (25 ms minimum; guaranteed at 35 ms
maximum), the device resets to the idle state (SDA released) and waits for a new START
condition. This ensures tha t the device never han gs up the bus if there ar e conflict s in the
transmission sequence. The bus fault time-out can be disabled during manufacture and
shipped under custom part number.
7.3 Slave address
To communicate with the device, the master must first address slave devices via a slave
address byte. The slave address byte consists of seven address bits, and a direction bit
indicating the intent of executing a read or write operation. The device features three
address pins to allo w up to 27 devic es to be addressed on a sing le bu s in te r fac e. Table 5
describes the pin logic levels used to properly connect up to 27 8-pin devices. Table 6
describes the pin logic levels used to properly connect up to three 6-pin devices.
‘1’ indicates the pin is connected to the supply (VCC); ‘0’ indicates the pin is connected to
GND; ‘Float’ indicates the pin is left unconnected. The states of pins A0/A1/A2 are
sampled only at power-up. After sampling the address is latched to minimize power
dissipation associated with detection.
Table 5. PCT2075 address table (SO8, TSSOP8, HWSON8 packages)
No. Address pin coding Slave address
A2 A1 A0
1 0 0 0 1001 000
2 0 0 1 1001 001
3 0 1 0 1001 010
4 0 1 1 1001 011
5 1 0 0 1001100
6 1 0 1 1001101
7 1 1 0 1001110
8 1 1 1 1001111
9 floating 0 0 1110 000
10 floating 0 floating 1110 001
11 floating 0 1 1110 010
12 floating 1 0 1110 011
13 floating 1 floating 1110 100
14 floating 1 1 1110 101
15 floating floating 0 1110 110
16 floating floating 1 1110 111
17 0 floating 0 0101 000
18 0 floating 1 0101 001
19 1 floating 0 0101 010
20 1 floating 1 0101 011
21 0 0 floating 0101 100
22 0 1 floating 0101 101
23 1 0 floating 0101 110
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.4 Register list
The PCT2075 contains four data registers beside the pointer register as listed in Table 7.
The pointer value, read/write capability and default content at power-up of the registers
are also shown in Table 7.
24 1 1 floating 0101 111
25 0 floating floating 0110 101
26 1 floating floating 0110 110
27 floating floating floating 0110 111
Table 6. PCT2075 address table (TSOP6 package)
No. Address pin coding Slave address
A0
1 float 1001 000
2 0 1001 001
3 1 1001 010
Table 5. PCT2075 address table (SO8, TSSOP8, HWSON8 packages) …continued
No. Address pin coding Slave address
A2 A1 A0
Table 7. Register table
Register
name Pointer
value R/W POR
state Description
Conf 01h R/W 00h Configuration register: contains a single 8-bit data
byte; to set the device operating condition; default = 0.
Temp 00h read only 0000h Temperature register: contains two 8-bit data bytes;
to store the measured Temp data.
Tos 03h R/W 5000h Overtemperature shutdown threshold register:
contains two 8-bit data bytes; to store the
overtemperature shutdown Tots limit; default = 80 C.
6E00h Default = 110C for PCT2075GV/P110 only.
FB00h Default = -5C for PCT2075GV/N005 only.
Thyst 02h R/W 4B00h Hysteresis register: contains two 8-bit data bytes;
to store the hysteresis Thys limit; default = 75 C.
6900h Default = 105C for PCT2075GV/P11 0 only.
F600h Default = -10C for PCT2075GV/N005 only.
Tidle 04h R/W 00h Temperature conversion cycle default to 100 ms.
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.4.1 Pointer register
The Pointer regi ster contains an 8-bit data byte, of wh ich the thr ee LSB bits represent the
pointer value of the other five registers, and the other five MSB bits are equal to 0, as
shown in Table 8 and Table 9. The Pointer register is not accessible to the user, but is
used to select the data register for write/read operation by including the pointer data byte
in the bus comma nd .
Because the Pointer value is latched into the Pointer register when the bus command
(which includes the pointer byte) is executed, a r ead from the device may or may not
include the pointer byte in th e statement. To read again a register that has been recently
read and the pointer has been preset, the pointer byte does not have to be included. To
read a register that is different from the one that has been recently read, the pointer byte
must be included. However, a write to the device must always include the pointer byte in
the statement. The bus communica tion protocols are described in Section 7.10.
At power-up, the Pointer value is equal to 000b and the Temp register is selected; users
can then read the Temp data without specifying the pointer byte.
Anything not shown in Table 9 is reserved and should not be used.
Table 8. Pointer register
B7 B6 B5 B4 B3 B[2:0]
00000pointer value
Table 9. Pointer value
B2 B1 B0 Selected register
0 0 0 Temperature register (Temp)
0 0 1 Configuration register (Conf)
0 1 0 Hysteresis register (Thyst)
0 1 1 Overtemperature shutdown register (Tos)
1 0 0 Idle register (Tidle)
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.4.2 Configuration register
The Configuration register (Conf) is a write/read register and contains an 8-bit
non-complement data byte that is used to configure the device for different operation
conditions. Table 10 shows the bit assignments of this register.
7.4.3 Temperature register
The Temperature register (Temp) holds the digital result of temperature measurement or
monitor at the end of each analog-to-digital conversion. This register is read-only and
contains two 8-bit data bytes consisting of one Most Significan t Byte (MSByte) and one
Least Significant Byte (LSByte). However , only 1 1 bits of those two bytes are used to store
the Temp data in two’ s complement format with the resolution of 0.125 C. Table 11 shows
the bit arrangement of the Temp data in the data bytes.
When reading register Temp, all 16 bits of the two data bytes (MSByte and LSByte) are
provided to the bus and should be all collected by the controller for a valid temperature
reading. However, only the 11 most significant bits should be used, and the five least
significant bits of the LSByte are zero and sh ould be ignored. One of the ways to calculate
the Temp valu e in C from the 11-bit Temp data is:
1. If the Temp data MSByte bit D10 = 0, then the temperature is positive and Temp value
(C) = +(Temp data) 0.125 C.
2. If the Temp data MSByte bit D10 = 1, then the temperature is negative and
Temp value (C) = (two’s complement of Temp data) 0.125 C.
Table 10. Conf register
Legend: * = default value.
Bit Symbol Access Value Description
B[7:5] reserved R/W 000* unused; any value written to these bits does not
affect operation
B[4:3] OS_F_QUE[1:0] R/W OS fault queue programming
00* queue value = 1
01 queue value = 2
10 queue value = 4
11 queue value = 6
B2 OS_POL R/W OS polarity selection
0* OS active LOW
1 OS active HIGH
B1 OS_COMP_INT R/W OS operation mode selection
0* OS comparator
1 OS interrupt
B0 SHUTDOWN R/W device operation mode selection
0* normal
1 shutdown
Table 11. Temp regi ster
MSByte LSByte
7654321076543210
D10D9D8D7D6D5D4D3D2D1D0 X X X X X
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Examples of the Temp data and va lue are shown in Table 12.
For 9-bit Temp data application in repl acing the industry standard LM75, just use only
9 MSB bits of the two bytes and disregard 7 LSB of the LSByte. The 9-bit Temp data with
0.5 C resolution of the device is defined exactly in the same way as for the standard
LM75 and it is here similar to the Tos and Thyst registers.
A single byte read (MSByte) of the Temp register is allowed. Then the temperature
resolution is 1.00 C instead.
7.4.4 Overtemperature shutdown threshold (Tos) and hysteresis (Thyst) registers
These two registers, are write/read r egister s, and also called set-po int reg isters. They ar e
used to store the user-defined temperature limits, called overtemperature shutdown
threshold (Tots) and hysteresis temperature (Thys), for the device watchdog operation. At
the end of each conversion the Temp data is compared with the dat a stored in these two
registers in order to set the state of the device OS output; see Section 7.1.
Each of the set-point registers cont ains two 8-bit dat a bytes consisting of one MSByte and
one LSByte in the same format as the Temperature register. However, only 9 bits of th e
two bytes are used to store the set-point data in two’s complement format with the
resolution of 0.5 C. Table 13 and Table 14 show the bit arrangement of the Tos data and
Thyst data in the data bytes.
Notice that because only 9-bit data are used in the set-point registers, the device uses
only the 9 MSB of the Temp data for data comparison.
Table 12. Temp register valu e
11-bit binary
(two’s complement) Hexadecimal value Decimal value Value
011 1111 1000 3F8 1016 +127.000 C
011 1111 0111 3F7 1015 +126.875 C
011 1111 0001 3F1 1009 +126.125 C
011 1110 1000 3E8 1000 +125.000 C
000 1100 1000 0C8 20 0 +25.000 C
000 0000 0001 001 1 +0.125 C
000 0000 0000 000 0 0.000 C
111 1111 1111 7FF 10.125 C
111 0011 1000 738 200 25.000 C
110 0100 1001 649 439 54.875 C
110 0100 1000 648 440 55.000 C
Table 13. Tos register
MSByte LSByte
7654321076543210
D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X X
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I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
When a set-point register is read, all 16 bits are provided to th e bus and must be collected
by the controller for a valid temperature. However, only the 9 most significant bits should
be used and the 7 LSB of the LSByte are equal to zero and should be ignored.
A single byte read of either Tos or Thyst is allowed.
Table 15 shows examples of the limit data and value.
7.4.5 Tidle register
For the device temperature sensor, the temperature is measured periodically to save
power. When the temperature is being measured, the device burns approximately 70 A
active current. Since the ambient temper ature changes slowly, it is unnecessary to let the
temperature measurem ent co ntinuously active. Instead , the dev ice temperature sensor is
set to idle for a user-specified time to save power after temperature measurement is done.
The Tidle register allows users to specify the sampling period to measure the
temperature. The register is composed of 5-bit values TIDLE[4:0] at pointer address 04h.
The values of TIDLE[7:5] are ‘don’t care’ and have no effect on the temperature
measurement period. The temperature measurement period can be calculated by
TIDLE[4:0] 100 ms. For example, if TIDLE[4:0] = 00001, the temperature sampling is
‘00001’ 100 ms = 100 ms. the temperature sensor allows a sampling period from
100 ms to 3.1 s by programming Tidle. If Tidle is set to ‘00000’, it is treated the same as
Tidle = ‘00001’ and the temperature sensor measures temperature at 100 ms period.
Table 14. Thyst register
MSByte LSByte
7654321076543210
D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X X
Table 15. Tos and Thyst limit data and value
11-bit binary
(two’s complement) Hexadecimal value Decimal value Value
0 1111 1010 0FA 250 +125.0 C
0 0011 0010 032 50 +25.0 C
0 0000 0001 001 1 +0.5 C
0 0000 0000 00 0 0 0.0 C
1 1111 1111 1FF 10.5 C
1 1100 1110 1CE 50 25.0 C
1 1001 0010 192 110 55.0 C
Table 16. Tidle - Temperature idle register (address 04h) bit allocation
Temperature idle register contains the value of time in between temperature measurements.
TIDLE[4:0] is the 5-bit Tidle value. Tidle
100 ms is the temperature sampling period.
Bit 7 6 5 4 3 2 1 0
Symbol - - - TIDLE[4] TIDLE[3] TIDLE[2] TIDLE[1] TIDLE[0]
Reset - - -00001
Access - - - R/W R/W R/W R/W R/W
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Product data sheet Rev. 10 — 20 November 2017 14 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
The device temperature sensor powers up to measure temperature every 100 ms, with
Tidle = 00001 by default. For the PCT2075 with 11-bit accuracy, the ADC conversion is
about 28 ms. As a result, the PCT2075 is idle for (1 00 ms 28 ms) = 72 ms between two
temperature meas urements.
7.5 OS output and polarity
The OS output is an open-drain output and its state represents results of the device
watchdog operation as descri bed in Section 7.1. In order to obse rve this output state, an
external pull-up resistor is needed. The resistor should be as large as possible, up to
1.5 k, to minimize the Temp reading error du e to inter nal heating by the high OS sinking
current.
The OS output active state can be selected as HIGH or LOW by programming bit B2
(OS_POL) of register Conf: setting bit OS_POL to logic 1 selects OS active HIGH and
setting bit B2 to logic 0 sets OS active LOW. At power-up, bit OS_POL is equal to logic 0
and the OS active state is LOW.
7.6 OS comparator and interrupt modes
As described in Section 7.1, the device OS outp ut responds to the result of the
comparison between register Temp data and the programmed limits, in registers Tos and
Thyst, in different ways depending on the selected OS mode: OS comparator or
OS interrupt. The OS mode is selected by programming bit B1 (OS_COMP_INT) of
register Conf: setting bit OS_COMP_INT to logic 1 selects the OS interrupt mode, and
setting to logic 0 selects the OS compar ator mode. At power-up, bit OS_COMP_INT is
equal to logic 0 and th e OS co mparat or is selected.
The main difference between the two modes is that in OS comp arator mode, the OS
output becomes active when Temp has e xceeded T ots and reset when Temp has dropp ed
below Thys, reading a register or putting the device into shutdown mode does not change
the state of the OS output; while in OS interrupt mode, once it has been activated either
by exceeding Tots or dropping below Thys, the OS output remains active indefinitely until
reading a register, then the OS output is reset.
Temperature limits Tots and Thys must be selected so that Tots > Thys. Otherwise, the OS
output sta te is undefined.
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Product data sheet Rev. 10 — 20 November 2017 15 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.7 OS fault queue
Fault queue is defined as the number of faults that must occur consecutively to activate
the OS output. It is provided to avoid false tripping due to noise. Because faults are
determined at th e en d of data conver sio ns , fault queue is also defined as the number of
consecutive conversions returning a temperature trip. The value of fault queue is
selectable by programming the two bits B4 and B3 (OS_F_QUE[1:0 ]) in register Conf.
Notice that the programmed data and the fault queue value are not the same. Table 17
shows the one-to-one relationship between them. At power-up, fault queue data = 0 and
fault queue value = 1.
7.8 Shutdown mode
The device operation mode is selected by programming bit B0 (SHUTDOWN) of register
Conf. Setting bit SHUTDOWN to logic 1 puts the device into shut down mode. Resetting bit
SHUTDOWN to logic 0 returns the device t o norm a l mode .
In shutdown mode, the PCT2075 draws a small current of <1.0 A and the power
dissipation is minimized; th e tem p er at ur e co nv er sio n sto ps, but the I 2C-bus interface
remains active and register write/read operat ion can be per formed. When th e shut down is
set, the OS output is unchanged in comparator mode and reset in interrupt mode.
7.9 Power-up default and power-on reset
The PCT2075 always powers-up in its default state with:
•Normal operation mode
•OS comparator mode
•Tots = 80 C (or as specified for the custom part number)
•Thys = 75 C (or as specified for the custom part number)
•OS output active state is LOW
•Pointer value is logic 000 (Temp)
•SMBus time-out enabled (or as specified for the custom part number)
When the power supply voltage is dropped below the device power-on reset level of
approximately 1.0 V (POR) for over 2 s and then rises up again, th e PCT 2075 is r eset to
its default condition as listed above.
In some applications a higher or lower default Tots and Thys values or no SMBus time-out
may be required. Please contact NXP for information on custom part number.
Table 17. Fault queue table
Fault queue data Fault queue value
OS_F_QUE[1] OS_F_QUE[0] Decimal
001
012
104
116
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Product data sheet Rev. 10 — 20 November 2017 16 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
7.10 Protocols for writing and reading the registers
The communication between the host and the device must strictly follow the rules as
defined by the I2C-bus management. The protocols for device register read/write
operations are illustrated in Figure 8 to Figure 13 to gether with the following definitions:
1. Before a communication, th e I 2C- bu s must be free or no t b usy. It m ean s th at th e SCL
and SDA lines must both be released by all devices on the bus, and they become
HIGH by the bus pull-u p re sist or s.
2. The host must provide SCL clock pulses necessary for the communication. Data is
transferred in a sequence of 9 SCL clock pulses for every 8-bit data byte followed by
1-bit status of the acknowledgement.
3. During data transfer, except the START and STOP signals, the SDA signal must be
stable while the SCL signal is HIGH. It means that the SDA signal can be changed
only during the LOW du ra tio n of the SCL line.
4. S: START signal, initiated by the host to start a communication, the SDA goes from
HIGH to LOW while the SCL is HIGH.
5. RS: RE-START signal, same as the START signal, to start a read command that
follows a write command.
6. P: STOP signal, generated by the host to stop a communication, the SDA goes from
LOW to HIGH while the SCL is HIGH. The bus becomes free thereafter.
7. W: write bit, when the write/read bit = LOW in a write com m a nd .
8. R: read bit, when the write/read bit = HIGH in a read command.
9. A: device acknowledge bit, returned by the device. It is LOW if the device works
properly and HIGH if not. The host must release the SDA line during this period in
order to give the device the control on the SDA line.
10. A’: master acknowledge bit, not returned by the device, but set by the master or host
in reading 2-byte data. During this clock period, the host must set the SDA line to
LOW in order to notify the device that the first byte has been read for th e de vice to
provide the second byte onto the bus.
11. NA: Not Acknowledge bit. During this clock period, both the device and host release
the SDA line at the end of a data transfer, the host is then enabled to generate the
STOP signal.
12. In a write protocol, data is sent from the host to the device and the host controls the
SDA line, except during the clock period when the device sends the device
acknowledgement signal to the bus.
13. In a read protocol, d at a is sent to the bus by the device and the host must release the
SDA line during the time th at the device is providing d at a onto the bus and contro lling
the SDA line, except during the clock period when the master sends the master
acknowledgement signal to the bus.
14. For best temperature accuracy both temperature bytes should be read as shown in
Figure 12 and Figure 13, bu t for a quick less a ccurate check/r educe bus tr ansmission
then only one byte, the MSByte, needs to be read as shown in Figure 10.
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Product data sheet Rev. 10 — 20 November 2017 17 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
(1) See Table 5 or Table 6 for device address.
Fig 8. Write configuration register (1-byte data)
002aah777
1
B6SSDA
SCL
B5B4B3B2B1B0WA 00000001A 000D4D3D2D1D0A P
23456789123456789123456789
START STOP
write device
acknowledge
device
acknowledge
device
acknowledge
device address(1) pointer byte configuration data byte
(1) See Table 5 or Table 6 for device address.
Fig 9. Read configuration register including pointer byte (1-byte data)
002aah778
SCL
SDA
(next)
(next)
123456789123456789
device address(1) pointer byte
START RE-START
write device
acknowledge
device
acknowledge
SCL (cont.)
SDA (cont.)
123456789123456789
device address(1) data byte from device
STOP
read master not
acknowledged
device
acknowledge
D7 D6 D5 D4 D3 D2 D1 D0 PB6 B5 B4 B3 B2 B1 B0 R A NA
00000001A
RS
B6
SB5 B4 B3 B2 B1 B0 W A
(1) See Table 5 or Table 6 for device address.
Fig 10. Read configuration or temp register with preset pointer (1-byte data)
002aah779
START
S
SCL
SDA
123456789123456789
device address
(1)
data byte from device
STOP
read master not
acknowledged
device
acknowledge
D7 D6 D5 D4 D3 D2 D1 D0 PB6 B5 B4 B3 B2 B1 B0 R A NA
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Product data sheet Rev. 10 — 20 November 2017 18 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
(1) See Table 5 or Table 6 for device address.
Fig 11. Write Tos or Thyst register (2-byte data)
002aah780
123456789123456789
D7SDA (cont.)
SCL (cont.)
D6 D5 D4 D3 D2 D1 D0 A D7 D6 D5 D4 D3 D2 D1 D0 A P
B6SSDA
SCL
B5 B4 B3 B2 B1 B0 W A 0 0 0 0 0 0 P1 P0 A (next)
(next)
123456789123456789
device address(1) pointer byte
MSByte data LSByte data
START write device
acknowledge
device
acknowledge
STOP
device
acknowledge
device
acknowledge
(1) See Table 5 or Table 6 for device address.
Fig 12. Re ad Temp, Tos or Thyst register including pointer byte (2-byte data)
123456789
123456789123456789123456789
B6 B5 B4 B3 B2 B1 B0 R A D7 D6 D5 D4 D3 D2 D1 D0 A' D7 D6 D5 D4 D3 D2 D1 D0 NA P
1234567890
B6S B5 B4 B3 B2 B1 B0 W A 0 0 0 0 0 0 P1 P0 A (next)
(next)
SDA
SCL
SDA (cont)
SCL (cont)
RS
002aah781
device address(1) pointer byte
device address(1) MSByte from device LSByte from device
START RE-START
write device
acknowledge
device
acknowledge
read master
acknowledge
master not
acknowledged
device
acknowledge
STOP
(1) See Table 5 or Table 6 for device address.
Fig 13. Read Temp, Tos or T hyst register with preset pointer (2-byte da ta)
123456789123456789123456789
B6S B5B4B3B2B1B0 R A D7D6D5D4D3D2D1D0 A' D7D6D5D4D3D2D1D0NA P
SDA
SCL
002aah782
device address(1) MSByte from device LSByte from device
START read master
acknowledge
master not
acknowledged
device
acknowledge
STOP
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Product data sheet Rev. 10 — 20 November 2017 19 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
8. Application design-in information
8.1 Typical application
8.2 Temperature accuracy
Because the local channel of the temperature sensor measures its own die temperature
that is transferred fr om its body, the temperature of the device body must be st abilized and
saturated for it to provide the stable readings. Because the device operates at a
low-power level, the thermal gradient of the device package has a minor effect on the
measurement. The accuracy of the measurement is more dependent upon the definition
of the environment temperature, which is affected by different factors: the printed-circuit
board on which the device is mounted; the air flow contacting the device body (if the
ambient air temperature and the printed-circuit board temperature are much diffe rent,
then the measurement may not be stable because of the different thermal paths between
the die and the environment). The st abilized temperature liquid of a thermal bath provides
the best temperature environm ent when the d evice is completely dipped into it. A ther ma l
probe with the device mounted inside a sealed-end metal tube located in consistent
temperature air also provides a good method of temperature measurement.
8.3 Noise effect
The device design includes the implementation of basic features for a good noise
immunity:
•The 50 ns low-pass filter on both the bus pins SCL and SDA;
•The hysteresis of the threshold volt ages to the bus inpu t signals SCL and SDA, about
500 mV minimum;
•All pins have ESD protection circuitry to prevent damage during electrical surges. The
ESD protection on the address, OS, SCL and SDA pins it to ground. The latch- back
based device br ea kd o wn vo ltage of add res s/OS is typically 11 V and SCL/SDA is
typically 9.5 V at any supp ly vo ltage but varies over process and temperature. Since
Fig 14. PCT2075 typical application
002aag640
0.1 μF
1.5 kΩ
DIGITAL LOGIC
PCT2075 DETECTOR OR
INTERRUPT LINE
BUS
PULL-UP
RESISTORS
I2C-BUS
8
2
SCL
SDA
A2
A1
A0
5
6
1
74
3OS
VCC
power supply
GND
1.5 kΩ1.5 kΩ
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Product data sheet Rev. 10 — 20 November 2017 20 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
there are no protection diodes from SCL or SDA to VCC, the device will not hold the
I2C lines LOW when VCC is not supplied and therefore allows continued I2C-bus
operation if the device is de-powered.
However, good layout practices and extra noise filters are re commended when th e device
is used in a very noisy environ m en t:
•Use decoupling capacitors at VCC pin.
•Keep the digital trace s away from switching power supplies.
•Apply proper terminations for the long board traces.
•Add capacitors to the SCL and SDA lines to increase the low-pass filter
characteristics.
9. Limiting values
10. Recommended operating conditions
Table 18. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol Parameter Conditions Min Max Unit
VCC supply voltage 0.3 +6.0 V
VIinput voltage at input pins 0.3 +6.0 V
IIinput current at input pins 5.0 +5.0 mA
IO(sink) output sink current on pin OS - 60 mA
VOoutput voltage on pin OS 0.3 +6.0 V
Tstg storage temperature 65 +150 C
Tjjunction temperature - 150 C
Table 19. Recommended operating characteristics
Symbol Parameter Conditions Min Typ Max Unit
VCC supply voltage 2.7 - 5.5 V
Tamb ambient temperature 55 - +125 C
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Product data sheet Rev. 10 — 20 November 2017 21 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
11. Static characteristics
[1] Typical values are at VCC = 3.3 V and Tamb =25C.
[2] Or values as specified for custom part number. See Table 7.
Table 20. Static characteristics
VCC = 2.7 V to 5.5 V; Tamb =
55
C to +125
C; unless otherwise specified.
Symbol Parameter Conditions Min Typ[1] Max Unit
Tacc temperature accuracy Tamb = 25 C to +100 C1-+1C
Tamb = 55 C to +125 C2-+2C
Tres temperature resolution 11-bit digital temp data - 0.125 - C
tconv(T) temperature conversion
time normal mode - 28 - ms
Tconv conversion period normal mode - 0.1 3.2 s
VPOR power-on reset voltage - - 2.6 V
ICC(AV) average supply current normal mode: I2C-bus inactive - 125 300 A
normal mode: I2C-bus active;
fSCL = 1000 kHz -200400A
shutdown mode
Tamb =25C-<0.1-A
Tamb =85C-<1-A
Tamb =125C--20A
VIH HIGH-level input voltage digital pins (SCL, SDA, A2 to A0) 0.7 VCC -V
CC +0.3 V
VIL LOW-level input voltage digital pins 0.3 - 0.3 VCC V
VI(hys) hysteresis of input voltage SCL and SDA pins - 300 - mV
A2, A1, A0 pins - 150 - mV
IIH HIGH-level input current digital pins; VI=V
CC
Tamb =25C-<0.1-A
Tamb =85C
(PCT2075D, DP and TP only) -<1-A
Tamb =85C (PCT2075GV only) - <2 - A
Tamb =125C
(PCT2075D, DP and TP only) --10A
Tamb =125C (PCT2075GV only) - - 20 A
IIL LOW-level input current d igital pins; VI = 0 V 1.0 - +1.0 A
VOL LOW-level output voltage OS pin; IOL =20mA - - 0.4 V
SDA pin; IOL =20mA - - 0.4 V
ILO output leakage current SDA and OS pins; VOH =V
CC --20A
Nfault number of faults programmable; conversions in
overtemperature-shutdown fault
queue
1-6
TBovertemperature
shutdown temperature default value - 80[2] -C
Thys hysteresis temperat ure default value - 75[2] -C
Ciinput capacitance digital pins - 20 - pF
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Product data sheet Rev. 10 — 20 November 2017 22 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 15. Average su pply current ver sus temperature;
I2C-bus inac tiv e Fig 16. Average supply current versus temperature;
I2C-bus activ e
Fig 17. Shutdown mode supply current
versus temperature Fig 18. LOW-level output voltage on OS pin
versus temperature; IOL =4mA
Fig 19. LOW-leve l ou tpu t curre nt on OS pin
versus temperature; VOL =0.4V Fig 20. LOW-level input current versus temperature;
digital pins
100
150
50
200
250
IDD
(μA)
0
Tamb (°C)
−75 12575−25 25
002aah437
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
0
300
200
100
400 002aah438
IDD
(μA)
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
4
6
2
8
10
IDD
(μA)
0
Tamb (°C)
−75 12575−25 25
002aah439
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
0
0.30
0.20
0.10
0.40 002aah440
VOL
(V)
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
0
60
40
20
80 002aah441
IOL
(mA)
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
−0.2
0.2
−0.6
0.6
1.0
IIL
(μA)
−1.0
Tamb (°C)
−75 12575−25 25
002aah442
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
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Product data sheet Rev. 10 — 20 November 2017 23 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 21. HIGH-level input current versus temperature;
digital pins Fig 22. LOW-level output voltage on SDA pin
versus temperature; IOL =20mA
Fig 23. LOW-level ou tpu t current on SDA pin
versus temperature; VOL =0.4V Fig 24. Temperature accuracy versus temperature;
VCC =2.8V to 5.5V
Fig 25. Power-on reset threshold voltage
versus temperature; rising VCC
Fig 26. Power-on reset voltage versus temperature;
falling VCC
4
6
2
8
10
IIH
(μA)
0
Tamb (°C)
−75 12575−25 25
002aah443
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
0
0.30
0.20
0.10
0.40 002aah453
VOL
(V)
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
0
60
40
20
80 002aah454
IOL
(mA)
VDD = 5.5 V
4.5 V
3.3 V
2.7 V
Tamb (°C)
−75 12575
−25 25
−2.0
1.0
0
−1.0
2.0 002aah444
Tacc
(°C)
1.0
2.0
3.0
Vth(POR)
(V)
0
Tamb (°C)
−75 12575−25 25
002aah451
1.0
2.0
3.0
VPOR
(V)
0
Tamb (°C)
−75 12575−25 25
002aah452
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Product data sheet Rev. 10 — 20 November 2017 24 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
12. Dynamic characteristics
[1] These specifications are guaranteed by design and not tested in production.
[2] This is the SDA time LOW for reset of serial interface.
[3] Holding the SDA line LOW for a time greater than tto causes the device to reset SDA to the idle state of the serial bus communication
(SDA set HIGH).
Table 21. I2C-bus interface dynamic characteristics[1]
VCC = 2.7 V to 5.5 V; Tamb =
55
C to +125
C; unless otherwise specified.
Symbol Parameter Conditions Min Typ Max Unit
fSCL SCL clock frequency see Figure 27 20 - 1000 kHz
tHIGH HIGH period of the SCL clock 0.26 - - s
tLOW LOW period of the SCL clock 0.5 - - s
tHD;STA hold time (repeated) START condition 0.26 - - s
tSU;DAT dat a set-up time 50 - - ns
tHD;DAT data hold time 0 - - ns
tSU;STO set-up time for STOP condition 0.26 - - s
tffall time SDA and OS outputs;
CL= 450 pF; IOL =30mA -120-ns
tto(SMBus) SMBus time-out time [2][3] 25 - 35 ms
Fig 27. Timing diagram
SDA
SCL
002aah456
t
f
SSr P S
t
HD;STA
t
LOW
t
r
t
SU;DAT
t
f
t
HD;DAT
t
HIGH
t
SU;STA
t
HD;STA
t
SP
t
SU;STO
t
r
t
BUF
0.7 × V
CC
0.3 × V
CC
0.7 × V
CC
0.3 × V
CC
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Product data sheet Rev. 10 — 20 November 2017 25 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
13. Package outline
Fig 28. Package outline SOT96-1 (SO8)
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PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 26 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 29. Package outline SOT505-1 (TSSOP8)
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PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 27 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 30. Package outline SOT1069-2 (HWSON8)
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 28 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 31. Package outline SOT1353-1 (TSOP6)
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 29 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
14. Soldering of SMD packages
This text provides a very brief insight into a complex technology. A more in-depth account
of soldering ICs can be found in Application Note AN10365 “Surface mount reflow
soldering description”.
14.1 Introduction to soldering
Soldering is one of the most common methods through which packages are attached to
Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both
the mechanical and the electrical connection. There is no single soldering method that is
ideal for all IC packages. Wave soldering is often preferred when through-hole and
Surface Mount Devices (SMDs) are mixed on on e printed wiring board; however, it is not
suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high
densities that come with increased miniaturization.
14.2 Wave and reflow soldering
W ave soldering is a joining te chnology in which the joints are m ade by solder coming from
a standing wave of liquid solder. The wave soldering process is suitable for the following:
•Through-hole components
•Leaded or leadless SMDs, which are glued to the surface of the printed circuit board
Not all SMDs can be wave soldered. Packages with solder balls, and some leadless
packages which have solde r lands underneath the body, cannot be wave soldered. Also,
leaded SMDs with leads ha ving a pitch smaller than ~0.6 mm cannot be wave soldered,
due to an increased probability of bridging.
The reflow soldering process involves applying solder paste to a board, followed by
component placement and exposure to a temperatur e profile. Leaded packages,
packages with solder balls, and leadless packages are all reflow solderable.
Key characteristics in both wave and reflow soldering are:
•Board specifications, including the board finish, solder masks and vias
•Package footprints, including solder thieves and orie ntation
•The moisture sensitivity level of the packages
•Package placement
•Inspection and repair
•Lead-free soldering ve rsus SnPb soldering
14.3 Wave soldering
Key characteristics in wave soldering are:
•Process issues, such as application of adhesive and flux, clinching of leads, board
transport, the solder wave parameters, and the time during which components are
exposed to the wave
•Solder bath specifications, including temperature and impurities
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 30 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
14.4 Reflow soldering
Key characteristics in reflow soldering are :
•Lead-free ve rsus SnPb soldering; note th at a lead-free reflow process usua lly leads to
higher minimum peak temperatures (see Figure 32) than a SnPb process, thus
reducing the process window
•Solder paste printing issues including smearing, release, and adjusting the process
window for a mix of large and small components on one board
•Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature) an d cooling down. It is imperative that the peak
temperature is high enoug h for the solder to make reliable solder joint s (a solder paste
characteristic). In addition, the peak temperature must be low enough that the
packages and/or boards ar e not damaged. The peak temperature of the package
depends on p ackage thickness and volume and is classified in accord ance with
Table 22 and 23
Moisture sensitivity precautions, as indicated on the packing, must be respected at all
times.
Studies have shown that small packages reach higher temperatures during reflow
soldering, see Figure 32.
Table 22. SnPb eutectic process (from J-STD-0 20D)
Package thickness (mm) Package reflow temperature (C)
Volume (mm3)
< 350 350
< 2.5 235 220
2.5 220 220
Table 23. Lead-free process (from J-STD-020D)
Package thickness (mm) Package reflow temperature (C)
Volume (mm3)
< 350 350 to 2000 > 2000
< 1.6 260 260 260
1.6 to 2.5 260 250 245
> 2.5 250 245 245
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 31 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
For further informa tion on temperature profiles, refer to Application Note AN10365
“Surface mount reflow soldering description”.
15. Soldering: PCB footprints
MSL: Moisture Sensitivity Level
Fig 32. Temperature profiles for large and small components
001aac844
temperature
time
minimum peak temperature
= minimum soldering temperature
maximum peak temperature
= MSL limit, damage level
peak
temperature
Fig 33. SOT96-1 (SO8); reflow soldering
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PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 32 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 34. SOT96-1 (SO8); wave soldering
Fig 35. SOT505-1 (TSSOP8); reflow sold ering
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PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 33 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Fig 36. SOT1069-2 (HWSON8); reflow soldering
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 34 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
16. Abbreviations
17. Revision history
Table 24. Abbreviations
Acronym Description
A-to-D Analog-to-Digital
CDM Charged Device Model
ESD ElectroStatic Discharge
HBM Human Body Model
I2C-bus Inter-Integrated Circuit bus
I/O Input/Output
LSB Least Significant Bit
LSByte Least Significant Byte
MSB Most Significant Bit
MSByte Most Significant Byte
PCB Printed-Circuit Board
POR Power-On Reset
SMD Solder Mask Defined
Table 25. Revision history
Document ID Release date Data sheet status Change notice Supersedes
PCT2075 v.1 0 20171120 Product data sheet - PCT2075 v.9.1
Modifications: •Removed “X” in part number PCT2075GV/N0 05X
•Section 4 “Ordering information”: Added PCT2075GV/P110
•Table 7 “Register table”: Added register information for PCT2075GV/P110
PCT2075 v.9 .1 20170421 Product data sheet - PCT2075 v.9
Modifications: •Section 4 “Ordering information”: Added PCT2075GV/N005X
•Table 7 “Register table”: Added register information for PCT2075GV/N005X
•Added Figure 1 “Cooling system using custom part PCT2075GV/N005”
PCT2075 v.9 20141 024 Product data sheet - PCT20 75 v.8
Modifications: •Table 1 “Ordering information”: Changed topside mark of PCT2075GV from ‘075’ to ‘20x’; added
Tab le note [1]
•Table 2 “Ordering options”: Added PCT2075GVX
PCT2075 v.8 20140 925 Product data sheet - PCT20 75 v.7
PCT2075 v.7 20140 306 Product data sheet - PCT20 75 v.6
PCT2075 v.6 20140 124 Product data sheet - PCT20 75 v.5
PCT2075 v.5 20131 209 Product data sheet - PCT20 75 v.4
PCT2075 v.4 20130 719 Product data sheet - PCT20 75 v.3
PCT2075 v.3 20130 521 Product data sheet - PCT20 75 v.2
PCT2075 v.2 20130 506 Product data sheet - PCT20 75 v.1
PCT2075 v.1 20130 405 Product data sheet - -
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 35 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
18. Legal information
18.1 Data sheet status
[1] Please consult the most recently issued document before initiating or completing a design.
[2] The term ‘short data sheet’ is explained in section “Definitions”.
[3] The product status of device (s) descr ibed in th is document m ay have cha nged since thi s document w as publish ed and may di ffe r in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
18.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warrant ies as to t he accuracy or completeness of
information included herein and shall have no liab ility for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and tit le. A short data sh eet is intended
for quick reference only and shou ld not b e relied u pon to cont ain det ailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semicond uctors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall pre va il.
Product specificat io n — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product is
deemed to off er functions and qualities beyon d those described in the
Product data sheet.
18.3 Disclaimers
Limited warr a nty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warrant ies, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information. NXP Se miconductors takes no
responsibility for the content in this document if provided by an information
source outside of NXP Semiconductors.
In no event shall NXP Semiconductors be liable for any indirect , incidental,
punitive, special or consequ ential damages (including - wit hout limitation - lost
profits, lost savings, business interruption, costs related to the removal or
replacement of any products or rework charges) whether or not such
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contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability t owards
customer for the products described herein shall be limited in accordance
with the Terms and conditions of commercial sale of NXP Semiconductors.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all informa tion supplied prior
to the publication hereof .
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
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malfunction of an NXP Semiconductors product can reasonably be expected
to result in perso nal injury, death or severe property or environmental
damage. NXP Semiconductors and its suppliers accept no liability for
inclusion and/or use of NXP Semiconducto rs products in such equipment or
applications and ther efore such inclu sion and/or use is at the cu stomer’s own
risk.
Applications — Applications that are described herein for any of these
products are for il lustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and ope ration of their applications
and products using NXP Semiconductors product s, and NXP Semiconductors
accepts no liability for any assistance with applications or customer product
design. It is customer’s sole responsibility to determine whether the NXP
Semiconductors product is suit able and fit for t he customer’s applications and
products planned, as well as fo r the planned application and use of
customer’s third party customer(s). Custo mers should provide appropriate
design and operating safeguards to minimize the risks associate d with t heir
applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party custo mer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and pro ducts using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by cust omer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress rating s only and (proper)
operation of the device at these or any other conditions above those given in
the Recommended operating conditions section (if presen t) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanently and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial sale — NXP Semiconductors
products are sold subject to the general terms and conditions of commercial
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agreed in a valid written individua l agreement. In case an individual
agreement is concluded only the ter m s and conditions of the respective
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applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
No offer to sell or license — Nothing i n this document may be interpreted or
construed as an of fer t o sell product s that is open for accept ance or the gr ant,
conveyance or implication of any license under any copyrights, patents or
other industrial or intellectual property rights.
Document status[1][2] Product status[3] Definition
Objective [short] data sheet Development This document contains data from the obj ective specification for product development.
Preliminary [short] dat a sheet Qualification This document contains data from the preliminary specification.
Product [short] data sheet Production This document contains the product specif ication.
PCT2075 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
Product data sheet Rev. 10 — 20 November 2017 36 of 37
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
Export control — This document as well as the item(s) described herein
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Non-automotive qualified products — Unless this data sheet expressly
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Semiconductors accepts no liability for inclusion and/or use of
non-automotive qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automot ive specifications and standards, custome r
(a) shall use the product without NXP Semiconductors’ warranty of the
product for such au tomotive applications, use and specifica tions, and (b)
whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconduct ors for an y
liability, damages or failed product claims resulting f rom customer design an d
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specif ications.
Translations — A non-English (translated) version of a document is for
reference only. The English version shall prevail in case of any discrepancy
between the translated and English versions.
18.4 Trademarks
Notice: All referenced b rands, produc t names, service names and trademarks
are the property of their respective ow ners.
I2C-bus — logo is a trademark of NXP Semi conductors N.V.
19. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
NXP Semiconductors PCT2075
I2C-bus Fm+ digital temperature sensor and thermal wa tchdog
© NXP Semiconductors N.V. 2017. All rights rese rved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
Date of release: 20 November 2017
Document identifier: PCT2075
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
20. Contents
1 General description. . . . . . . . . . . . . . . . . . . . . . 1
2 Features and benefits . . . . . . . . . . . . . . . . . . . . 2
3 Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
4 Ordering information. . . . . . . . . . . . . . . . . . . . . 3
4.1 Ordering options. . . . . . . . . . . . . . . . . . . . . . . . 3
5 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 4
6 Pinning information. . . . . . . . . . . . . . . . . . . . . . 4
6.1 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
6.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 5
7 Functional description . . . . . . . . . . . . . . . . . . . 6
7.1 General operation. . . . . . . . . . . . . . . . . . . . . . . 6
7.2 I2C-bus serial interface. . . . . . . . . . . . . . . . . . . 7
7.2.1 Bus fault time-out . . . . . . . . . . . . . . . . . . . . . . . 8
7.3 Slave address. . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.4 Register list. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.4.1 Pointer register . . . . . . . . . . . . . . . . . . . . . . . . 10
7.4.2 Configuration register . . . . . . . . . . . . . . . . . . . 11
7.4.3 Temperature register . . . . . . . . . . . . . . . . . . . 11
7.4.4 Overtemperature shutdown threshold (Tos) and
hysteresis (Thyst) registers. . . . . . . . . . . . . . . 12
7.4.5 Tidle register. . . . . . . . . . . . . . . . . . . . . . . . . . 13
7.5 OS output and polarity . . . . . . . . . . . . . . . . . . 14
7.6 OS comparator and interrupt modes . . . . . . . 14
7.7 OS fault queue . . . . . . . . . . . . . . . . . . . . . . . . 15
7.8 Shutdown mode . . . . . . . . . . . . . . . . . . . . . . . 15
7.9 Power-up default and power-on reset . . . . . . 15
7.10 Protocols for writing and re ading the registers 16
8 Application design-in information . . . . . . . . . 19
8.1 Typical application . . . . . . . . . . . . . . . . . . . . . 19
8.2 Temperature accuracy . . . . . . . . . . . . . . . . . . 19
8.3 Noise effect. . . . . . . . . . . . . . . . . . . . . . . . . . . 19
9 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 20
10 Recommended operating conditions. . . . . . . 20
11 Static characteristics. . . . . . . . . . . . . . . . . . . . 21
12 Dynamic characteristics . . . . . . . . . . . . . . . . . 24
13 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 25
14 Soldering of SMD packages . . . . . . . . . . . . . . 29
14.1 Introduction to soldering . . . . . . . . . . . . . . . . . 29
14.2 Wave and reflow soldering . . . . . . . . . . . . . . . 29
14.3 Wave soldering. . . . . . . . . . . . . . . . . . . . . . . . 29
14.4 Reflow soldering. . . . . . . . . . . . . . . . . . . . . . . 30
15 Soldering: PCB footprints. . . . . . . . . . . . . . . . 31
16 Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . 34
17 Revision history. . . . . . . . . . . . . . . . . . . . . . . . 34
18 Legal information . . . . . . . . . . . . . . . . . . . . . . 35
18.1 Data sheet status. . . . . . . . . . . . . . . . . . . . . . 35
18.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
18.3 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . 35
18.4 Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . 36
19 Contact information . . . . . . . . . . . . . . . . . . . . 36
20 Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37