IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 1/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Features
General
• Minimum number of inexpensive external components
• Auto shutdown in case of over temperature with internal or
external temperature sensor
• Small package allows compact module design with minimised
wire runs and short connections to achieve improved EMI
performance
• MLX10801 is offered in 2 package options: SOIC8 and MLPD8
5x5. The MLPD8 5x5 package option allows to take out a higher
peak and average current than the SOIC8 package option
LED driver
• High energy efficiency
• Light control via PWM possible
• Light output has a minimized dependency on supply and
temperature variations
• Adjustable LED parameters are stored in an internal
NV memory
Coil driver
• Additional use for driving coils like relays and micro valves in a
power saving mode
• Works with a wide range of coils
Electronic fuse
• Additional use as electronic fuse.
• Fuse current adjust possibility
VS
CALIB
TEST
DRVOUT
DSENSE
GND
RSENSE
10801
(SO8)
CONTR
VS
CALIB
TEST
DRVOUT
DSENSE
GND
RSENSE
MLX10801
(M LPD8
5x5)
CONTR
Orderi ng I nfor m ati on
Part Nr Temperature Code Package Code
MLX10801 R (-40°C to 105°C) DC (SOIC8)
MLX10801 R (-40°C to 105°C) LDC (MLPD8 5x5)
General Description
The MLX10801 is a multi-purpose LED driver for high power LEDs designed for automotive applications.
A lot of adjustment possibilities allow for the design of different LED applications using only a few external
components.
The circuit is load dump protected for a 40V load dump pulse.
As a second use, a variety of coils like relays and micro valves can be driven in a very efficient power saving mode.
A third use is a simple electronic fuse, to protect circuits from overcurrent or overtemperature.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 2/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Table of content
Features............................................................................................................................... 1
Ordering Information............................................................................................................1
General Description .............................................................................................................1
Table of content ................................................................................................................... 2
Block diagram ...................................................................................................................... 4
1. Typical application data............................................................................................. 5
1.1. LED driver applications .................................................................................... 5
1.1.1. Complete schematic LED driver diagram .................................................... 5
1.1.2. Minimum schematic LED driver diagram..................................................... 5
1.1.3. LED driver application notes ........................................................................ 6
1.1.3.1. LED driver application notes for MLX10801 in MLPD8 5x5 .................. 7
1.2. Coil driver applications ..................................................................................... 8
1.2.1. Coil driver schematic diagram ..................................................................... 8
1.2.2. Coil driver application notes......................................................................... 8
1.3. Electronic fuse applications.............................................................................. 9
1.3.1. Electronic fuse schematic diagram .............................................................. 9
1.3.2. Electronic fuse application notes ................................................................. 9
2. Application pins....................................................................................................... 10
3. Absolute maximum ratings ..................................................................................... 11
4. Electrical characteristics ......................................................................................... 13
5. EE-Latch characteristics ......................................................................................... 16
6. ESD/EMI recommendations for MLX10801............................................................ 16
7. Automotive test pulses............................................................................................ 17
7.1. Test pulse definition ....................................................................................... 18
8. LED driving principle ............................................................................................... 21
8.1. General........................................................................................................... 21
8.2. The principle in detail ..................................................................................... 22
8.3. Coil inductance, EMI and selected parameter set.......................................... 23
8.4. Switching frequency considerations and constant light output....................... 25
9. Coil driving principle................................................................................................ 26
9.1. General........................................................................................................... 26
9.2. The principle in detail ..................................................................................... 26
10. Electronic fuse principle .......................................................................................... 26
11. Sleep mode............................................................................................................. 27
12. Temperature shutdown........................................................................................... 27
13. Load dump protection ............................................................................................. 27
14. The calibration ........................................................................................................ 27
14.1. The internal control register ........................................................................... 27
14.2. The Influence of the pseudo random generator to the monoflop time ........... 29
14.3. The calibration interface................................................................................. 30
14.4. The calibration procedure .............................................................................. 31
14.4.1. Calibration procedure for LED driver applications ................................. 31
14.4.2. Calibration procedure for coil driver applications:.................................. 32
14.4.3. Calibration procedure for electronic fuse applications:.......................... 32
15. Data content of delivered parts ............................................................................... 33
16. Mechanical Data ..................................................................................................... 34
16.1. Mechanical data of the MLX10801 in SOIC8 ................................................. 34
16.2. Mechanical data of the MLX10801 in MLPD8 5x5 ......................................... 35
16.3. Melexis standard soldering information.......................................................... 38
17. History record.......................................................................................................... 39
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 3/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
18. Disclaimer ............................................................................................................... 41
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 4/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Block diagram
Serial interface
EE-Latches
DAC
COMP
FF
6 Bit Free running counter
DAC
COMP
Regulator
VDD
VDD
RSENSE
DRVOUT
DSENSE
TEST
CALIB
CONTR
GND
VS
COMP
VDD
Tresh.
detect.
Reference 3V+/-5%
Debouncing
time 32ms
Sleep
3 Bit Johnson
counter for jitter
on monoflop time
CLK
6 Bit Compare register as
programmable Monoflop
1 MHz oscillator
Divider / 1024
POR POR
VDD
EE-
Latch
EE-
Latch
EE-
Latch
Programmable devider:
not used;/1;/2;/4;/8;/16;/32
3 Bit devider selection for
delay generation after POR
CLK
POR
Stop
CLK Start
MonoflopDelay
Jitter
Test-
mode
detect.
Digital
Testmode
POR
Hysteresis
Debouncing
1us
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 5/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
1. Typical application data
1.1. LED driver applications
1.1.1. Complete schematic LED driver diagram
VS
GND
CALIB
TEST RSENSE
DSENSE
DRVOUT
CONTR
Diode only needed, in case
temperature shut off is done
with an external diode
temperature sensor
VBAT
CONTROL
GND
47k
100nF
Calibration point
Calibration
point
Calibration points
optional Cap for
EMC reduction
10...100uF
Cap for EMC directly
on the connector
100nF...1uF
1.1.2. Minimum schematic LED driver diagram
VS
GND
CALIB
TEST RSENSE
DSENSE
DRVOUT
CONTR
VBAT
GND
47k
100nF
Calibration point
Calibration
point
Calibration points
10...100uF
Cap for EMC directly
on the connector
100nF...1uF
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 6/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
1.1.3. LED driver application notes
The MLX10801 is optimised for the use of low cost coils. For a standard application with 1 LED and an average
current of 350mA a coil of about 100µH…470µH having ≤ 1R omic resistance should be chosen. The sense resistor
should have a value between 0.47R…1R / 250mW.
As a general rule: the higher the load current, the lower the inductance of the coil should be, since higher currents
lengthen the charging time of the coil. Switching frequencies lower than 20kHz are often not desired.
It is possible (without manipulating the internal IC trimming data) to set the peak current and the average current of
the LED by a variation of sense resistor and coil value. The same can be achieved by programming a modified
parameter set to the EEPROM of the IC.
The free wheel diode that carries the load current during the passive state (driver OFF) should be a very fast
switching diode like ES1D or BYG80 with a recommended trr<30ns in order to avoid parasitic spikes on RSENSE.
The diode must be able to carry the current flowing in the LED.
For applications that use an external temperature sensor, virtually any low cost diode with a temperature coefficient
of -2mV/K can be used.
In case of longer lines between the IC and the coil (which should be avoided because of EMI), a capacitor might be
placed in parallel to RSENSE to avoid crosstalk and parasitic switching.
A well chosen parameter set can help to avoid such a condition. The goal should be to unload the coil as much as
possible during the selected monoflop time (see as well chapter 8.3).
The schematic diagram under 1.1.1 is used in applications, where the LED is controlled by external control
electronics. A PWM with a frequency between 30Hz..4kHz can be applied to the CONTROL pin in order to
dim the light output. This frequency is limited by the debouncing time for the sleep mode on the lower side
and the selected monoflop time on the upper side of that range.
This function can be used to achieve different light outputs or also be used in a temperature down
regulation.
It is recommended to have the PWM frequency at least 5-10 times lower than the selected driver switching
frequency.
The minimum schematic diagram under 1.1.2 is sufficient for all applications with a constant light output.
Nevertheless a dimming function could be achieved by a PWM driving directly on the module supply.
In this mode, the PWM frequency should be chosen between 0 and 1kHz. It is limited by the maximum
IC settling time.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 7/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
1.1.3.1.LED driver application notes for MLX10801 in MLPD8 5x5
The MLX10801 assembled in a MLPD8 5x5 package allows to take out of the IC a higher average and a higher
peak current.
The pre calibration data of the MLX10801 in all types of packages is identical.
In order to take advantage of the bigger output current capability without changing the ICs pre trimmed parameter
set, the user can change the values of the coil and the sense resistor.
A typical LED average current of approx. 700mA can be achieved by using a coil of 220uH and a sense resistor of
0,3 Ohm.
In case of such typical high current applications, the user must provide a suitable heat sink possibility on the PCB.
Changing the pre calibrated data, which is stored in the internal EEPROM, allows to tune the IC also to other
coil and sense resistor values, the EMC performance can be influenced as well.
Please check as we ll out the MLX10801 application notes for different driving solutions,
which allow to drive more than one high power LED on a single MLX10801.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 8/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
1.2. Coil driver applications
1.2.1. Coil driver schematic diagram
VS
GND
CALIB
TEST RSENSE
DSENSE
DRVOUT
CONTR
VBAT
GND
47k
100nF
Calibration point
Calibration
point
Calibration points
optional cap for
EMC reduction
10...100uF
Cap for EMC directly
on the connector
RF
RSENSE
CF
COIL
1.2.2. Coil driver application notes
The purpose of this application is to drive a coil in a power saving efficient way using a switched mode power
supply. Coils of 10mH…5H can be driven. Attention has to be drawn to the maximum allowed current which
must not be exceeded.
In case of high inductive coils and/or longer cables between the IC and the coil, CF and RF might be needed for
reducing electromagnetic emissions.
When the driver switches on, the coil still contains a certain amount of energy, which is connected to a high voltage
on node COIL. Via the RDSon of the driver this voltage together with switching oscillations is then coupled to
RSENSE. If these switching oscillations do not disappear within the debouncing time of the comparator (typically
1µs) the driver is switched off immediately, an effect known as “parasitic switching”. A solution to that could be:
• CF, RDSon+ RF form a filter
• CF only acts in case the driver switches ON (in the OFF state it is quickly discharged by RSENSE)
• R
DSon + RF should be larger than RSENSE
• RSENSE and CF must be directly connected to pin RSENSE
• CF and RF must be figured out in the application. However, typical start values are RF=0 (not used)
and CF=1.5uF.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 9/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
The idea is to decouple the node COIL from RSENSE so that the switch off voltage can not be reached.
Thus, parasitic switching is avoided.
Instead of using RF and CF, “parasitic switching” can also be avoided by a well chosen parameter set
(see also chapter 8.3) and a well designed PCB that avoids switching oscillations.
Note: Melexis designed in a debouncing time of 1µs to the internal comparator due to the fact that the
MLX10801 can be used with a wide range of inductances.
1.3. Electronic fuse applications
1.3.1. Electronic fuse schematic diagram
VS
GND
CALIB
TEST RSENSE
DSENSE
DRVOUT
CONTR
VBAT
CONTROL
GND
47k
100nF
Calibration point
Calibration
point
Calibration points
10...100uF
RL
1.3.2. Electronic fuse application notes
The purpose of this application is the protection of an external load against overcurrent. In this mode, the switch
mode regulator is disabled. The driver is permanently ON as long as the current remains below a specified level.
Once this level is reached, the driver switches OFF and remains OFF until a POR is given.
A shutdown of the module due to overtemperature is also achievable if the internal or external temperature
sensor is used.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 10/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
2. Application pins
Nr. Name Function
1 VS Supply Voltage
2 GND Ground
3 TEST MELEXIS test pin for test modes enable
4 CALIB Serial clock/data for end of line programming
5 DSENSE External diode pin for temperature measurement and temperature shutdown condition
6 RSENSE External sense resistor pin for peak current detection
7 DRVOUT Driver output
8 CONTR Light control input, ON/OFF or dimming via PWM signal, sleep mode possibility
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 11/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
3. Absolute maximum ratings
Parameter Symbol Condition Min Max Unit
Power supply vs DC
max. 2h
max. 0.5s
-0.3
-0.3
-0.3
28
36
40
V
V
V
Maximum input current in protection circuitry
on any pin
iprot In case of
maximum
supply
ratings
-10 10 mA
Maximum input voltage on CONTR vicontr without
external
resistor
protected
with
external
47k
resistor
-0.3
-40V
(0.5s)
18
40
(0.5s)
V
V
Maximum input voltage on RSENSE,
DSENSE, TEST
vilv -0.3 vdd+0,3 V
Maximum input voltage on CALIB vicalib -0.3 18 V
Maximum input voltage on DRVOUT vdrvoutmax with load
DC
max. 2h
max. 0.5s
-0.3
-0.3
-0.3
28
36
40
V
V
V
Maximum peak current on DRVOUT for
MLX10801 in SOIC8
ipkdrvout 550 mA
Maximum average current on DRVOUT
for MLX10801 in SOIC8
iavgdrvout 400 mA
Maximum peak current on DRVOUT
for MLX10801 in MLPD8 5x5
ipkdrvout *) 1.2 A
Maximum average current on DRVOUT
for MLX10801 in MLPD8 5x5
iavgdrvout *) 750 mA
Maximum junction temperature
Lifetime
Dynamic
In case of EE Latch write
Storage temperature
tjunc
-40
-40
-40
-55
130
150
85
125
150 (100h)
C
C
C
C
C
Ambient temperature range tambient -40C 105 C
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 12/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Thermal resistance junction to ambient
for MLX10801 in SOIC8
rth 120 K/W
Thermal resistance junction to ambient
for MLX10801 in MLPD8 5x5
(Under consideration of the thermal
application notes for MLPD packages
published under www.carsem.com )
rth *) 37 K/W
*) The parameters are only valid, in case the specified rth is insured by having a suitable heat sink capability on the
PCB.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 13/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
4. Electrical characteristics
Following characteristics are valid
- for the full temperature range of T = -40°C to +105°C,
- a supply range of 28V ≥ VS > 6V
- and the IC settling time after power on reset
unless other conditions noted.
With 6V ≥ VS > vporh analog parameters can not be guaranteed.
Note: The correct operation of the MLX10801 as a switching mode power supply for voltages lower than the
nominal supply voltage is dependent on the forward bias voltage of the used LED.
The user must ensure that at low supply voltage the peak current threshold voltage on the RSENSE pin can
be reached in order to keep the switching principle working.
If several pins are charged with transients above VS and below GND, the sum of all substrate currents of the
influenced pins should not exceed 10mA for correct operation of the device.
Normal operating supply voltage is supposed to be 13.8V.
Parameter Symbol Conditions Limits Units
Min Typ Max
Global parameters
Maximum current during
40V load dump
ihv VS=40V
CONTR=H
10 mA
Normal supply current
at highest DC voltage
inomdch VS=28V
CONTR=H
4 mA
Normal supply current inom VS=13.8V
CONTR=H
2 mA
Sleep mode current isleep VS=13.8V
Chip in sleep
T=25C
105 µA
IC settling time
IC settling time after
power on reset
tsettle 300 µs
IC settling time after wake
up
tssettle 300 µs
Oscillator related parameters
The min/max specification influences directly all derived timings in the same deviation
Oscillator frequency fosc (frequency can
only be adjusted by
Melexis during final
parts test)
0.7 1.0 1.3 MHz
Debouncing time for sleep mode
Debouncing time on
CONTR for sleep mode
tdebsleep 32 ms
Wake up time twakeup 8 µs
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 14/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
RESET related parameters
Power on reset level, if
VS is ramped up
vporh (Reset is
connected to the
internal VDD, but
vporh is measured
on pin VS)
5.0 V
VDD related parameters (VDD stays only internal)
5V supply voltage range vdd VS=13.8V 4.0 5.5 V
Monoflop related parameters
Monoflop time tmon specified under 14.1
Delay time generation for current reduction after power on reset
Delay time tdelay specified under 14.1
DAC reference related parameters
DAC reference voltage vdacref 2,75 3 3,25 V
RSENSE related parameters
Input leakage current ileakrsense DRVOUT is
switched off
-5 5 µA
Minimum threshold
voltage on RSENSE of a
given step
vrsensemin specified under 14.1
Maximum threshold
voltage on RSENSE of a
given step
vrsensemax specified under 14.1
Stability of a selected step
due to temperature and
supply influence and long
term drift
vrsensestab -3
1) 3
1) %
DSENSE related parameters
Output leakage current ileakdsense CONTR=0 -5 5 µA
Output current for
temperature measure-
ment
idsense CONTR=1
(current can only
be adjusted by
Melexis during final
parts test)
80 120 µA
Minimum temperature
shutdown voltage on pin
DSENSE of a given step
vdsensemin specified under 14.1
Maximum temperature
shutdown voltage on pin
DSENSE of a given step
vdsensemax specified under 14.1
Hysteresis between
shutdown and switch on
for a selected trimming
step
vdsensehyst 13 35 mV
Stability of a selected step
due to temperature and
supply influence and long
term drift
vdsensestab -3
1) 3
1) %
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 15/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Temperature shutdown related parameters for the internal temperature sensor
Forward bias voltage of
internal diode at 25°C
vfwdrt idsense trimmed 630 660 690 mV
Forward bias voltage of
internal diode at 105°C
vfwdht idsense trimmed 460 490 520 mV
CONTR related parameters
Input leakage current ileakcontr -5 5 µA
Comparator digital
threshold level
L => H, switching point
vin5vhcontr
vdd=5V
0.6*vdd
3
0.65*vdd
3.25
0.7*vdd
3.5
V
V
Comparator digital
threshold level
H => L, switching point
vin5vlcontr
vdd=5V
0.3*vdd
1.5
0.35*vdd
1.75
0.4*vdd
2
V
V
DRVOUT related parameters
Input leakage of DRVOUT
when switched off
ileakdrvout -5 5 µA
On resistance of
DRVOUT @Tj=150C
rdsdrvout 1.4
Ω
CALIB related parameters
Pull down resistance of
pin CALIB
rpdcalib 5 10 20 k
1) Guaranteed by design
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 16/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
5. EE-Latch characteristics
The NV memory carrying the trimming information is composed of an EEPROM latch. The data, that is
written to this latch during final parts programming at Melexis or by the customer, is permanently stored
in this latch, even after the chip is powered down.
Data retention
25°C permanent ambient 20 years
55°C permanent ambient 20 years
85°C permanent ambient 10 years
125°C permanent ambient 1 year
6. ESD/EMI recommendations for MLX10801
• In order to minimise EMI, the PCB has to be designed according to EMI guidelines. Additional components may
be needed, other than what is shown in the application diagrams, in order to comply with
the EMI requirements.
• The MLX10801 is an ESD sensitive device and has to be handled according to EN100015 part 1.
• The MLX10801 will fulfil the requirements in the application according to the specification and to DIN 40839 part
1.
• The MLX10801 is designed with ESD protection >1000V HBM according to MIL883D.
• After ESD stress, the sleep mode current (specified in chapter 4) of the component can not be guaranteed
anymore.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 17/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
7. Automotive test pulses
The following chapter is valid for a completely assembled module. That means, that automotive test pulses are
applied to the module and not to the single IC.
In the recommended application according to chapter 1, the reverse polarity diode together with the capacitors
on the supply and the load dump protected IC itself protects the module against the automotive test pulses listed
below.
The exact values of the capacitors for the application have to be figured out according to the automotive and
EMI requirements.
No damage occurs for any of the test pulses.
A deviation of characteristics is allowed during pulse 1, 2, 4; the module returns to normal operation
after the pulse without any additional action.
During test pulse 3a, 3b, 5 the module operates within characteristic limits.
Parameter Symbol Min Max Dim Test condition,
Functional status
Transient test pulses in accordance to DIN40839 part 1&3 and ISO7637 part 1&3,
IC pin CONTR connected to IC pin VS via 47k, module schematics are according to application
notes. Module acts as a single light source
Test pulse #1 at module pin VBAT, GND vpulse1 -100 0 V 5000 pulses,
functional state C
Test pulse #2 at module pin VBAT, GND vpulse2 0 100 V 5000 pulses
functional state C
Test pulse #3a at module pin VBAT, GND vpulse3a -150 0 V 1h,
functional state A
Test pulse #3b at module pin VBAT, GND vpulse3b 0 100 V 1h,
functional state A
Test pulse #4 at module pin VBAT, GND vspulse4
vapulse4
-6
-5
-4
-2,5
V
V
1 pulse,
functional state C
Test pulse #5 at module pin VBAT, GND vpulse5 26,5 86,5 V 1 pulse clamped to <=40V
functional state C,
Description of functional status:
A: All functions of the module are performed as designed during and after the disturbance.
B: All functions of the module are performed as designed during and after the disturbance:
However, one or more can deviate from specified tolerance. All functions return automatically
to normal limits after exposure is removed. Memory functions shall remain class A.
C: A function of the module is not performed as designed during disturbance but returns automatically to
a normal operation after the disturbance
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 18/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
7.1. Test pulse definition
Test Pulse 1
Ri = 10R
vpulse1
10%
90%
1µs
2ms
200ms
<100µ
0.5s…5s
12V
V
t
Test pulse 2
Ri=10R
200ms
1µs
50µs
0.5…5s
10%
90%
vpulse2
12V
V
t
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 19/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Test Pulse 3a
Ri = 50R
12V
vpulse3a
100µs
10ms 90ms
10%
90%
5ns
100ns
t
V
Test Pulse 3b
Ri = 50R
12V
vpulse3b
100µs
10ms 90ms
90%
10%
5ns
100ns
t
V
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 20/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Test Pulse 4 (Cranking)
Ri = 0.01R
12V
vapulse4
vspulse4
5ms 0.5-20s
V
t
15ms 50
ms
100 ms
Test Pulse 5 (Load Dump)
Ri = 0.5…4R (clamped to 40V during test)
90%
10%
Pulse 5
Pulse 5 at
device
40V
td = 40...400ms
tr = 0.1...10ms
12V
V
t
vpulse5
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 21/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
8. LED dri v i ng princi pl e
8.1. General
The LED is driven by a switched mode power supply using an inductor as the energy storage element. This method
has several advantages. The supply voltage has to be set down to the forward bias voltage of the
LED. In ordinary applications this is achieved by a resistor with the following drawbacks:
- A resistor dissipates power which is transformed to heat
- Efficiency is reduced drastically
- The light output of the LED is dependent on the supply and the temperature of the resistor
The MLX10801 avoids this disadvantages as the following calculation shows (all values according to
the Melexis demo board EVB10801,standard configuration with L=220µH, RSENSE =0.47R):
Supposed:
Vbat = 13.8V
VfLED ≈ 3.4V
IfLED ≈ 350mA
Vf1 ≈ 0.7V (reverse polarity diode)
Vf2 ≈ 0.7V (free wheel diode)
VRSENSE ≈ 0.4V (@IfLED, RSENSE=0.47R)
VRDS ON ≈ 0.3V (@IfLED)
VCoil ≈ 0.2V (@IfLED)
Efficiency using a simple resistor:
Efficiency n: n = VfLED / Vbat ≈ 25%
Efficiency using the MLX10801:
The following calculation is an approximation only, due to the fact the coil current is not constant. It is therefore
calculated with average currents.
1) During OFF time, the coil acts as the storage element and puts its energy to the free wheel diode
and the LED:
n1 = VfLED / (VfLED+ Vf2+ VCoil) ≈ 79%
2) During ON time, current flows through the reverse polarity diode, LED, coil , FET driver and RSENSE,
which causes the following voltage drops:
n2= VfLED / (VfLED +Vf1 +VCoil +VRDS ON +VRSENSE ) ≈ 68%
3) ON and OFF times are in ratio of roughly 40:60
Efficiency n: n = (n1*0.4 + n2*0.6) = 72.4%
Measurements have given an efficiency of about 70% and confirm this estimation. Note, that the ratio of ON and
OFF time depends on many factors like supply voltage, coil inductance, forward bias voltage etc. and is therefore
an application specific value. For ordinary applications, efficiency ranges from about 65% - 75%.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 22/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
8.2. The principle in detail
The driver is switched on until a maximum current through the LED is reached. This maximum current is
programmable by the customer. After reaching the maximum current, the driver is switched off for an
adjustable monoflop time that is formed by a counter compare unit. The monoflop time is also programmable
by the customer. Both parameters, the peak current threshold voltage and the monoflop time, create an ON/OFF
period to form an average current through the LED. By programming these parameters, an adjustment of the
average load current is possible in a wide range.
Note: The current sense comparator has a typical debouncing time of 1µs as shown in the block diagram.
This delay time prevents the driver from being switched off due to short term switching oscillations etc.
When working with very short monoflop times this time has to be taken into account for calculations.
I
t
Imax
Iavg
tmon
Note: The circuit is active only in case CONTR=H.
By applying a PWM signal on CONTR, the LED can be dimmed from 0% to 100%.
CONTR=0 LED with 0%
CONTR=PWM LED dimmed with PWM
CONTR=H LED with 100%
Dimming can also be achieved by applying a PWM directly to the module supply.
IC settling times have always to be considered in PWM mode. Please refer also to chapter 1.1.3 for
additional PWM frequency considerations.
With a configuration bit, a pseudo random generator can be applied to the last 3 LSBs of the 6 setting bits for the
monoflop time. The pseudo random generator runs with the clock derived out of the monoflop time and adds
a random distribution on these 3 LSBs. Therefore, the monoflop time gets a random variation from its
trimmed value. This occurs in every monoflop period. It will influence the average current in the same
manner. By using this jitter mode feature, the EMI behaviour of the complete module is improved,
due to the variation of the otherwise fixed switching frequency.
Please refer to 14.2 for additional information.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 23/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
jitter mode
8.3. Coil inductance, EMI and selected parameter set
The inductance L of a coil describes the amount of magnetical energy that can be stored in it.
Consequently, high inductive coils will be discharged less than low inductive coils in a given time.
Generally the coil can be driven in two different ways:
1) The coil will only be discharged partially. That means the coil still carries a significant amount of energy
when going from discharging to charging. In that moment the charging current rises immediately to
the coil current that was flowing just before switching. This is connected with large dI/dt transients
on the RSENSE pin that have a negative impact on EMI.
2) The coil will be discharged completely. Thus, at the end of a discharging cycle, the coil doesn’t carry energy
anymore. With the next charging cycle, current increases steadily from around zero. This way,
large dI/dt transients are completely avoided.
Care has to be taken when working in jitter mode. In this case, monoflop time (=discharging time) is
not constant but varies in a certain range (see chapter 14.2 for details). It must be ensured that only
the longest possible monoflop time completely discharges the coil. Otherwise the coil is discharged
before the monflop time ends which results in a loss of efficiency.
I
t
Imax1
Iavg
tmon1
tmon2
Imax2
Conclusion: In most cases the coil is driven in a combination of both ways. A tradeoff has to be made between
EMI behaviour and maximum allowed LED current. By varying these parameters, an optimum can be found for
virtually every application.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 24/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Below are some examples for typical parameter sets given for a 350mA LED current and the following
application data:
Standard application used according to 1.1.1:
• RSENSE = 0.47R (1R)
• LED: Luxeon LXHL-MW1C
• L = 220µH, 470µH
L=470µH, RSENSE=1R
;Selection of temperature sensor (1-internal). Bit[19].
1
;Jitter enabled (1-enabled). Bit [18].
1
;Delay after POR. Bits [17:15].
000
;Temperature shut off. Bits [14:10].
01001
;TMonoflop time. Bits [9:4].
100100
;Peak current. Bits [3:0].
1111
w
L=220µH, RSENSE=0.47R
;Selection of temperature sensor (1-internal). Bit[19].
1
;Jitter enabled (1-enabled). Bit [18].
1
;Delay after POR. Bits [17:15].
000
;Temperature shut off. Bits [14:10].
01001
;TMonoflop time. Bits [9:4].
011100
;Peak current. Bits [3:0].
0111
w
L=100µH, RSENSE=0.47R
;Selection of temperature sensor (1-internal). Bit[19].
1
;Jitter enabled (1-enabled). Bit [18].
1
;Delay after POR. Bits [17:15].
000
;Temperature shut off. Bits [14:10].
01001
;TMonoflop time. Bits [9:4].
001100
;Peak current. Bits [3:0].
0111
w
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 25/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
8.4. Switching frequency considerations and constant light output
As already shown, the switching frequency depends on the peak current as well as on the monoflop time for a given
coil. Furthermore it depends on the coil inductance itself.
Due to the principle of switch mode power supplies, the current through the LED is kept constant for any
supply changes. The parameter that changes in order to keep the current constant is the switching
frequency itself. The lower the supply voltage, the lower the switching frequency. Furthermore, the supply
current is affected by supply changes: with an increasing supply voltage the average supply current decreases.
Melexis delivers the MLX10801 with a pre-trimmed parameter set according to chapter 15, where an average
switching frequency for a supply voltage of 13.8V is given.
The graph below shows the relative luminous flux versus the power supply for a typical application.
The luminous flux at 14V has been set to 100%. The graph indicates that the light output is not as
dependent on supply changes.
MLX10801 wit h Luxeon LX HL BBO 1, blue
Relat ive Lumi nous Fl ux
Tv/Tv(14V) =f(Vbat)
0,97
0,98
0,99
1,00
1,01
1,02
1,03
1,04
1,05
1,06
1,07
10 12 14 16 18 20 22 24 26 28 30
Vbat [V]
Tv/Tv(14V)
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 26/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
9. Coil drivi ng principle
9.1. General
Coils like relays or micro valves consume a relatively large amount of energy. At the moment of switching on,
energy is needed in order to switch a relay or a micro valve to the ON position. Once this position is reached,
the energy can be reduced drastically, while still keeping the mechanics of the relay or micro valve activated.
9.2. The principle in detail
After power on reset, a delay time tdelay can be enabled, which disables the peak current detection during that
time. This delay time can be selected as described in 14.
The maximum current Imax that can flow during tdelay, is just dependent on the omic resistance of the selected
coil. After tdelay, the trimmed configuration is valid and the current drops down to the trimmed current value Iavg.
Due to the fact that the inductance of relays and micro valves is quite high, the monoflop operation in the range
of microseconds does not have much of an impact on the average current. So, in this configuration the selected
peak current is nearly the same as the average current. The monoflop time should be selected according to the
inductance of the selected coil and for the best EMI behaviour.
I
t
Imax
Iavg
tdelay
tmon
10. Electronic fuse principle
The principle is very simple. The monoflop will not be used and stays deselected. This way, the driver is always
on and the current of a given load is sensed by RSENSE. If it exceeds the specified limit or the selected shutdown
temperature, the module will be switched off. It can only be switched on again by a power on reset to the
system or by reducing the module temperature.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 27/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
11. Sleep mode
In case CONTR=0 for t>tdebsleep, the MLX10801 goes to sleep mode, which reduces the IC current
drastically. Only the internal regulator and the input comparator for CONTR are still working.
In case CONTR=1 again, the chip is waken up after t>twakeup.
The settling time for wake up, given in chapter 4, has to be considered.
12. Temperature shutdown
The temperature shutdown feature can be enabled or disabled. In case it is enabled, an internal or external diode
can be used as temperature sensor.
The internal temperature sensor is used to protect the chip (FET driver) from overtemperature. If the adjustable
temperature shutdown voltage, which is in fact the forward bias voltage of the diode, is reached, the IC shuts
down. An external temperature sensor is usually used to protect the load (LED) from overtemperature. Therefore
it should be thermally connected to the load.
Between the temperature shutdown and release point, there is a hysteresis in order to avoid oscillations.
When this point is reached, the IC automatically returns to its normal mode.
The hysteresis is specified in chapter 4.
The thermal behaviour of the system should be characterised during the design-in of the product by the
customer. The chip can be programmed for a fixed temperature shutdown voltage thereafter during the
end of line programming.
For a system that is designed for thermal conditions, temperature shutdown may not be needed. In this case, the
temperature shutdown can be disabled completely.
13. Load dump protecti on
The MLX10801 is protected against 40V load dump, in case the application proposals described under 1 are used.
14. The calibration
14.1. The internal control register
The internal control register consists of the following bits.
Bits are shifted in from MSB to LSB, starting with Bit19 and ending with Bit0.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 28/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Nr of
Bits
Bits Scope Remark
Peak current shutdown calibration data.
The DAC behaviour is monotonic.
vrsensetyp stepwide is 30mV
Bits vrsensemin vrsensetyp vrsensemax
3 2 1 0
0 0 0 0 -10 % 90 mV +10 %
0 0 0 1 -10 % 120 mV +10 %
…
4 0…3
1 1 1 1 -10 % 540 mV +10 %
Monoflop time calibration data.
Bits Monoflop time tmon
9 8 7 6 5 4
0 0 0 0 0 0 Monoflop disabled
0 0 0 0 0 1 1 µs
0 0 0 0 1 0 2 µs
…
6 4…9
1 1 1 1 1 1 63 µs
Temperature shutdown calibration data.
The DAC behaviour is monotonic.
vdsensetyp stepwide is 10mV
Bits vdsensemin vdsensetyp vdsensemax
14 13 12 11 10
0 0 0 0 0 Temperature shutdown disabled
0 0 0 0 1 -10 % 300mV +10 %
0 0 0 1 0 -10 % 310mV +10 %
…
5 10…14
1 1 1 1 1 -10 % 600mV +10 %
Delay generation after power on reset for current reduction.
Bits Delay time tdelay
17 16 15
0 0 0 Delay time generation disabled
0 0 1 1 ms
0 1 0 2 ms
0 1 1 4 ms
1 0 0 8 ms
1 0 1 16 ms
1 1 0 32 ms
3 15…17
1 1 1 64 ms
Bit cleared Bit set
1 18 Pseudo random generator is
NOT applied to the monoflop
time generation.
Pseudo random generator is
applied to the monoflop time
generation.
1 19 External diode temperature
sensor is used at DSENSE.
Internal temperature diode
sensor is used at DSENSE.
4 20…23 Temperature shutdown current source calibration data.
5 24…28 Oscillator frequency calibration data.
5 29…33 DAC reference calibration data.
Only adjustable by
Melexis
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 29/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
14.2. The Influence of the pseudo random generator to the monoflop time
Code dez Code bin Monoflop- Jitter Jitter 1/ Monoflop- 1/Jitter 1/Jitter
dez bin Time min max Time max min
[us] [us] [us] [kHz] [kHz] [kHz]
1 000001 1 1 7 1000,0 1000,0 142,9
2 000010 2 1 7 500,0 1000,0 142,9
3 000011 3 1 7 333,3 1000,0 142,9
4 000100 4 1 7 250,0 1000,0 142,9
5 000101 5 1 7 200,0 1000,0 142,9
6 000110 6 1 7 166,7 1000,0 142,9
7 000111 7 1 7 142,9 1000,0 142,9
8 001000 8 8 14 125,0 125,0 71,4
9 001001 9 8 14 111,1 125,0 71,4
10 001010 10 8 14 100,0 125,0 71,4
11 001011 11 8 14 90,9 125,0 71,4
12 001100 12 8 14 83,3 125,0 71,4
13 001101 13 8 14 76,9 125,0 71,4
14 001110 14 8 14 71,4 125,0 71,4
15 001111 15 8 14 66,7 125,0 71,4
16 010000 16 16 22 62,5 62,5 45,5
17 010001 17 16 22 58,8 62,5 45,5
18 010010 18 16 22 55,6 62,5 45,5
19 010011 19 16 22 52,6 62,5 45,5
20 010100 20 16 22 50,0 62,5 45,5
21 010101 21 16 22 47,6 62,5 45,5
22 010110 22 16 22 45,5 62,5 45,5
23 010111 23 16 22 43,5 62,5 45,5
24 011000 24 24 30 41,7 41,7 33,3
25 011001 25 24 30 40,0 41,7 33,3
26 011010 26 24 30 38,5 41,7 33,3
27 011011 27 24 30 37,0 41,7 33,3
28 011100 28 24 30 35,7 41,7 33,3
29 011101 29 24 30 34,5 41,7 33,3
30 011110 30 24 30 33,3 41,7 33,3
31 011111 31 24 30 32,3 41,7 33,3
32 100000 32 32 38 31,3 31,3 26,3
33 100001 33 32 38 30,3 31,3 26,3
34 100010 34 32 38 29,4 31,3 26,3
35 100011 35 32 38 28,6 31,3 26,3
36 100100 36 32 38 27,8 31,3 26,3
37 100101 37 32 38 27,0 31,3 26,3
38 100110 38 32 38 26,3 31,3 26,3
39 100111 39 32 38 25,6 31,3 26,3
40 101000 40 40 46 25,0 25,0 21,7
41 101001 41 40 46 24,4 25,0 21,7
42 101010 42 40 46 23,8 25,0 21,7
43 101011 43 40 46 23,3 25,0 21,7
44 101100 44 40 46 22,7 25,0 21,7
45 101101 45 40 46 22,2 25,0 21,7
46 101110 46 40 46 21,7 25,0 21,7
47 101111 47 40 46 21,3 25,0 21,7
48 110000 48 48 54 20,8 20,8 18,5
49 110001 49 48 54 20,4 20,8 18,5
50 110010 50 48 54 20,0 20,8 18,5
51 110011 51 48 54 19,6 20,8 18,5
52 110100 52 48 54 19,2 20,8 18,5
53 110101 53 48 54 18,9 20,8 18,5
54 110110 54 48 54 18,5 20,8 18,5
55 110111 55 48 54 18,2 20,8 18,5
56 111000 56 56 62 17,9 17,9 16,1
57 111001 57 56 62 17,5 17,9 16,1
58 111010 58 56 62 17,2 17,9 16,1
59 111011 59 56 62 16,9 17,9 16,1
60 111100 60 56 62 16,7 17,9 16,1
61 111101 61 56 62 16,4 17,9 16,1
62 111110 62 56 62 16,1 17,9 16,1
63 111111 63 56 62 15,9 17,9 16,1
Monoflop-Time=f(code)
0
10
20
30
40
50
60
70
0 102030405060 70
Code
Monoflop-Time [us
]
Monoflop-Time [us]
Jitter min [us]
Jitter max [us]
1/Monoflop-Time=f(code)
0,0
200,0
400,0
600,0
800,0
1000,0
1200,0
0 10203040506070
Code
1/Monofloptime / kH
z
1/Monoflop-Time [kHz]
1/Jitter max [kHz]
1/Jitter min [kHz]
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 30/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
In case the pseudo random generator is enabled, a random value is applied to the 3 LSBs of the trimmed monoflop
time. The table above shows the relation between programmed monoflop time and the minimum/maximum
jitter, which can be seen in the related diagrams. All values are typical values. Note, that this is not the
drivers switching frequency but only the discharging cycle of a full switching period.
14.3. The calibration interface
The calibration interface consists of two blocks: The calibration pin (threshold detection) and the serial interface.
The calibration pin is a multi level pin and handles the following functions:
- sending clock and data to the serial interface
- latching the data to the EE-Latches
- programming the data to the EE-Latches
The pin itself is pulled down internally.
On pin CALIB, comparators are connected with the following threshold levels:
Threshold level Scope
0 Normal application mode
3*VS/10 Detects a logic “L” and generates a clock pulse
5*VS/10 Detects a logic “H” and generates a clock pulse
7*VS/10 Latches the data from the serial interface to the EE-Latches and generates a clock pulse.
Data is not stored permanently but will be immediately used
9*VS/10 Programmes the data permanently to the EE-Latches and generates a clock pulse.
Attention:
• A write cycle has to take 4ms…6ms. The user has to insure this time in order to
guarantee the specified EE-Latch data retention.
• Note, that the interface is fully static, thus only the threshold level is important.
However, the maximum transmission rate is limited to 20kBaud, which allows
50µs/bit.
• Note, that the CALIB pin needs to be left open (internally pulled down) in normal
application mode. If the threshold for programming is reached mistakenly (e.g. by
applying VBAT to pin CALIB), random data of the internal registers of the serial interface
will be programmed to the EE-Latches! It is even better to pull down CALIB hard to GND
after programming to avoid fail programming
• It is not possible to write a single bit to the EEPROM. A programming cycle always
consists of ALL bits of the scan chain.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 31/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
Following graph shows the driving of the pin and the modes:
0V
1*VS/5
2*VS/5
VS
3*VS/5
4*VS/5
Clock
Data
1*VS/10
3*VS/10
5*VS/10
7*VS/10
9*VS/10
Data=L
Data=H LLL LH HLL
Scan in Latch data and
try the
application
Scan in of new data Latch and try
data in the
application
Data is O.K. and will be
programmed to the EE-
Latch,
Intervall of 4ms...6ms
t
V(CALIB)
14.4. The calibration procedure
The simple end of line calibration algorithms described below give the possibility to use only
• VS,
• GND,
• CALIB as communication interface. No other signals need to be driven.
However, depending on the application requests, other calibration algorithms which stimulate RSENSE
and/or DSENSE are also possible.
14.4.1.Calibration procedure for LED driver applications
An end of line calibration of LED modules is recommended due to the variation in brightness of high power
LEDs at a given current. Assembled modules need to have the CALIB pin available for programming by the
customer during the end of line programming. Optical feedback, such as a light meter, can be used during
the end of line calibration for the adjustment of the LED brightness.
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 32/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
The following configuration parameters are trimmed using a configuration, that has been figured out during the
design in phase:
- Monoflop time
- Jitter enabled or disabled
- Temperature shutdown voltage
- Internal or external temperature sensor used
- Delay generation after power on reset disabled
The following algorithm can be used for the configuration of the LED module:
A) A start value for the peak current threshold voltage is used.
B) It is loaded and latched via CALIB together with the data above.
C) A power on reset is applied and the application is started.
D) The light output is measured and a new code for the peak current threshold voltage is calculated.
E) The new code is loaded and latched via CALIB together with the data above.
F) The routines C)…E) are executed until the specified light output is reached.
14.4.2.Calibration procedure for coil driver applications:
The module is assembled completely. End of line programming is performed at the customers side. The
CALIB pin must be available for programming.
An ampere meter is connected in the supply line of the module.
The following configuration parameters are uploaded using a configuration, that has been figured out during the
design in phase:
- Peak current threshold voltage
- Monoflop time
- Delay generation after power on reset
- Jitter enabled or disabled
- Temperature shutdown voltage
- Internal or external temperature sensor used
The following algorithm can now be used:
A) The parameters above are uploaded and latched via CALIB.
B) A power on reset is applied and the application is started.
C) The relay or micro valve current is measured and must be in spec after tdelay.
14.4.3.Calibration procedure for electronic fuse applications:
The module is assembled completely. End of line programming is performed at the customers side.
The CALIB pin must be available for programming.
The following configuration parameters are uploaded using a configuration, that has been figured out during the
design in phase:
- Peak current threshold voltage
- Monoflop (stays deselected)
- Delay generation after power on reset (is switched off)
- Jitter (stays disabled)
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 33/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
- Temperature shutdown voltage
- Internal or external temperature sensor is used
The following algorithm can now be used:
A) The parameters above are uploaded and latched via the CALIB pin.
B) A power on reset is applied and the application is started.
C) The application is working. Adding additional current to the load will switch off the load if the sum of both
currents is larger than the trimmed limit.
15. Data content of delivered parts
All parts delivered to a customer have the following default parameter set, which had been programmed to the
IC during Melexis’ final part test. It is up to the user to modify this data depending on application requests
(see also chapter 14).
Application diagram according to 1.1.1:
• RSENSE = 0.47R,
• L= 220µH,
• LED: Luxeon LXHL-MW1C.
Meaning Parameter Type Unit
Average current iavg 350 mA
Resulting average switching frequency
(jitter mode enabled) at 13.8V
fdrvout
24 kHz
Delay generation switched off
Jitter mode enabled
Internal temperature sensor selected, calibrated to 150°C IC junction temperature
for thermal IC protection
The related parameter set file looks like following:
;Selection of temperature sensor (1-internal). Bit[19].
1
;Jitter enabled (1-enabled). Bit [18].
1
;Delay after POR. Bits [17:15].
000
;Temperature shut off. Bits [14:10]. (code 9 = 380mV).
01001
;TMonoflop time. Bits [9:4]. (code 28 = 28µs)
011100
;Peak current. Bits [3:0]. (code 7 = 300mV)
0111
w
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 34/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
16. Mechanical Data
16.1. Mechanical data of the MLX10801 in SOIC8
DIMENSIONS
INCHES MILLIMETERS
Note
MIN. NOM. MAX
MIN. NOM. MAX
A .061 .064 .068 1.55 1.63 1.73
A1 .004 .006 .0098 0.127 0.15 0.25
A0 .055 .058 .061 1.40 1.47 1.55
B .0138 .016 .0192 0.35 0.41 0.49
C .0075 .008 .0098 0.19 0.20 0.25
D .189 .194 .196 4.80 4.93 4.98
E .150 .155 .157 3.81 3.94 3.99
e .050 1.27
H .230 .236 .244 5.84 5.99 6.20
h .010 .013 .016 0.25 0.33 0.41
L .016 .025 .035 0.41 0.64 0.89
oc 0° 5° 8° 0° 5° 8° Degrees
X .085 .093 .100 2.16 2.36 2.54
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 35/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
16.2. Mechanical data of the MLX10801 in MLPD8 5x5
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 36/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 37/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 38/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
16.3. Melexis standard soldering information
This Melexis device is classified and qualified regarding soldering technology, solderability and moisture sensitivity
level, as defined in this specification, according to following test methods:
• IPC/JEDEC J-STD-020
Moisture/Reflow Sensitivity Classification For Nonhermetic Solid State Surface Mount Devices (classification
reflow profiles according to table 5-2)
• EIA/JEDEC JESD22-A113 Preconditioning of Nonhermetic Surface Mount Devices Prior to Reliability Testing
(reflow profiles according to table 2)
• CECC00802 Standard Method For The Specification of Surface Mounting Components (SMDs) of Assessed
Quality
• EIA/JEDEC JESD22-B106 Resistance to soldering temperature for through-hole mounted devices
• EN60749-15 Resistance to soldering temperature for through-hole mounted devices
• MIL 883 Method 2003 / EIA/JEDEC JESD22-B102
Solderability
For all soldering technologies deviating from above mentioned standard conditions (regarding peak temperature,
temperature gradient, temperature profile etc) additional classification and qualification tests have to be agreed
upon with Melexis.
The application of Wave Soldering for SMD's is allowed only after consulting Melexis regarding assurance of
adhesive strength between device and board.
Based on Melexis commitment to environmental responsibility, European legislation (Directive on the Restriction of
the Use of Certain Hazardous substances, RoHS) and customer requests, Melexis has installed a Roadmap to
qualify their package families for lead free processes also.
Various lead free generic qualifications are running, current results on request.
For more information on Melexis lead free statement see quality page at our website:
http://www.melexis.com/html/pdf/MLXleadfree-statement.pdf
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 39/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
17. History record
Rev. No. Change Date
1 1 Creation 21.09.01
2 1 IC settling times added 27.09.01
2 Minimum application diagram added
3 Efficiency calculation had been corrected
4 Calibration of the monoflop time had been changed
5 Debouncing time on CONTR for going to sleep mode added
6 Maximum ambient temperature for chip operation set to 105C
7 rth of the SOIC8 inserted, inomdch added
8 vs, ihv, inom, rdsdrvout adjusted
3 1 Pseudo random generator on the monoflop time added in order to improve EMI 04.10.01
4 1 Changes due to coil driver applications and electronic fuse applications 19.10.01
2 tbds have been defined
5 1 Device number MLX10801 assigned 16.11.01
2 Typing mistakes corrected
3 Maximum supply ratings now at 28V for industrial micro valve applications
4 tssettle set to 300us, -vbe replaced to –0.3V, ihv (typical) removed
5 Reset related parameters adjusted
6 Hysteresis for the temperature shutdown has been put in the block diagram
7 CALIB related parameters added to the electrical characteristics
6 1 Possible caps added for EMI improvement 15.01.02
2 Calibration procedure adjusted
3 Gain stages out of the RSENSE and DSENSE path have been removed
4 DSENSE is in tristate in case the internal temperature sensor is used
5 Twakeup=8us introduced in order not to wake up in case of HF on the pin CONTR
7 1 Pins DSENSE and RSENSE exchanged: pinning had been finalised 14.02.02
2 Melexis standard soldering information added
8 1 uF Capacitor added on the supply line for automotive test pulses 11.03.02
2 Chapter to automotive test pulses added
3 Data set added, which is stored in the devices to be delivered to a customer
4 Forward bias voltage vfwdlt replaced by vfwdrt
9 1 Exchange of the pin order of CALIB and TEST 15.05.02
10 1 Chapter “Data content of parts to be delivered” redefined: values, conditions 10.07.02
2 Application remark to the free wheel diode added: fast recovery time
3 Chapter “Switch frequency considerations” added
4 Pull down resistance on CALIB adjusted
11 1 Application schematics adjusted according to EMI results 27.09.02
2 Some additional application remarks have been added
3 iavgdrvoutr as parameter removed
4 Mechanical package drawings inserted
5 Application remarks for the PWM frequency added
6 Correction of the efficiency calculation
7 Relation between trimmed monoflop time and pseudo random generator jitter has
been added
8 Por levels adjusted
12 1 Spec of idsense adjusted 16.11.02
2 Chapter coil driver applications adjusted: “parasitic switching”, CF, RF introduced
3 Graph “relative luminous flux versus power supply” has been added
4 Calibration procedure adjusted
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 40/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
5 vdsensehyst specified as absolute voltage
6 ipeak removed as a specified value for the parts to be delivered
13 1 Block diagram because of coil driving principle adjusted 27.02.03
2 LED driver and coil driver application diagrams and -notes have been adjusted
3 Remark to MLX10801 applications below nominal supply voltage has been added
4 vfwdrt, vfwdht specified
5 rdsdrvout, vdd, vporh, idsense, vdsensehyst respecified; vporhyst removed
6 Chapter “Coil inductance, EMI and selected parameter set“ has been added
7 Coil driving principle adjusted
8 Influence of the pseudo random generator to the monoflop time adjusted
9 Trimming algorithms simplified
14 1 Addition of Ordering Information and Disclaimer 15.03.03
2 Layout changes
15 1 Adjustment of the parameter set of the parts to be delivered. Definition of the coil
value and sense resistor, to what this parameter set will fit.
25.03.03
16 1 vpor, isleep, vdacref, fosc respecified 29.10.03
2 Added remark, that the comparator on RSENSE is debounced with typ. 1µs
3 Added remark, that high voltage on Calib will program the IC as already shown in the
timing diagram
4 ESD respecification according to HBM
17 1 Idsense, vfwdht respecified 29.10.03
18 1 Explanations refined, example calculation adapted 10.12.03
19 1 Typing mistakes as well as formatting errors corrected 11.02.04
2 Working current changed to supply current in table electrical characteristics
3 “Johnson counter” corrected to “pseudo random generator”
4 Figure jitter mode corrected to true start-up behaviour and jitter
20 1 “Preliminary” statement removed 14.05.04
2 Melexis standard soldering information exchanged
21 1 Specification for the package option MLX10801 in MLPD8 5x5 has been worked in,
as well. For both versions there is now only one specification valid.
14.07.05
2 Exchange of SOIC8 package drawings for better visibility
3 Absolute maximum ratings: 36V for max 2h added as condition, vdrvoutmax re-
specified
IC specification MLX10801
Power LED driver for automotive applications
Power saving low side coil driver
Electronic fuse
3901010801 Page 41/41 Rev 021 14/July/05
Author: TFR revised: RAH/SSZ
18. Disclaimer
Devices sold by Melexis are covered by the warranty and patent indemnification provisions appearing in its Term of
Sale. Melexis makes no warranty, express, statutory, implied, or by description regarding the information set forth
herein or regarding the freedom of the described devices from patent infringement. Melexis reserves the right to
change specifications and prices at any time and without notice. Therefore, prior to designing this product into a
system, it is necessary to check with Melexis for current information. This product is intended for use in normal
commercial applications. Applications requiring extended temperature range, unusual environmental requirements,
or high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not
recommended without additional processing by Melexis for each application.
The information furnished by Melexis is believed to be correct and accurate. However, Melexis shall not be liable to
recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of
profits, loss of use, interrupt of business or indirect, special incidental or consequential damages, of any kind, in
connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or
liability to recipient or any third party shall arise or flow out of Melexis’ rendering of technical or other services.
© 2002 Melexis NV. All rights reserved.
For the latest version of this document, go to our website at:
www.melexis.com
Or for additional information contact Melexis Direct:
Europe and Japan: All other locations:
Phone: +32 13 61 16 31 Phone: +1 603 223 2362
E-mail: sales_europe@melexis.com E-mail: sales_usa@melexis.com
QS9000, VDA6.1 and ISO14001 Certified
