DS75LV Digital Thermometer and Thermostat General Description The DS75LV low-voltage (1.7V to 3.7V) digital thermometer and thermostat provides 9, 10, 11, or 12-bit digital temperature readings over a -55C to +125C range with 2C accuracy over a -25C to +100C range. At power-up, the DS75LV defaults to 9-bit resolution for software compatibility with the LM75. Communication with the DS75LV is achieved through a simple 2-wire serial interface. The DS75LV thermostat has a dedicated open-drain output (OS) and programmable fault tolerance, which allows the user to define the number of consecutive error conditions that must occur before OS is activated. There are two thermostatic operating modes that control thermostat operation based on user-defined trip-points (TOS and THYST). Applications Benefits and Features Extend Performance Range with Low-Voltage, 1.7V to 3.7V Operating Range Maximize System Accuracy in Broad Range of Thermal Management Applications * Measures Temperature from -55C to +125C (-67F to +257F) * 2C Accuracy over a -25C to 100C Range * User-Configurable Resolution from 9 Bits (Default) to 12 Bits (0.5C to 0.0625C) Easy Upgrade to LM75: Pin and Software Compatible Simplify Distributed Temperature-Sensing Applications with Multidrop Capability * Up to Eight DS75LVs Can Operate on 2-Wire Bus Increase Reliability and System Robustness * Internally Filtered Data Lines for Noise Immunity (50ns Deglitch) * Bus Timeout Feature Prevents Lockup on 2-Wire Interface Personal Computers Cellular Base Stations Office Equipment Any Thermally Sensitive System Ordering Information appears at end of data sheet. Minimize Power Consumption with Built-In Shutdown Mode Flexible User-Defined Thermostatic Modes with Programmable Fault Tolerance Functional Block Diagram PRECISION REFERENCE OVERSAMPLING MODULATOR DIGITAL DECIMATOR VDD CONFIGURATION REGISTER SCL SDA A0 A1 A2 ADDRESS AND I/O CONTROL TEMPERATURE REGISTER OS TOS AND THYST REGISTERS GND 19-7469; Rev 5; 11/16 DS75LV THERMOSTAT COMPARATOR RP DS75LV Digital Thermometer and Thermostat Absolute Maximum Ratings Voltage on VDD, Relative to Ground.....................-0.3V to +4.0V Voltage on Any Other Pin, Relative to Ground ....-0.3V to +6.0V Operating Temperature Range.......................... -55C to +125C Storage Temperature Range............................. -55C to +125C Lead Temperature (soldering, 10s).................................. +260C Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC Electrical Characteristics (1.7V VDD 3.7V, TA = -55C to +125C, unless otherwise noted.) PARAMETER SYMBOL Supply Voltage VDD Thermometer Error (Note 1) TERR Input Logic-High Input Logic-Low VIH VIL CONDITIONS MIN MAX UNITS 3.7 V -25 to +100 2.0 C -55 to +125 3.0 0 to +50 0.5 (Note 2) 0.7 x VDD (Note 2) -0.5 SDA Output Logic Low Voltage (Note 2) VOL1 3mA sink current 0 VOL2 6mA sink current 0 OS Saturation Voltage VOL 4mA sink current (Notes 1, 2) Input Current Each I/O Pin I/O Capacitance CI/O Standby Current IDD1 Active Current (Notes 3, 4) IDD TYP 1.7 0.4 < VI/O< 0.9 x VDD 5.5 V 0.3 x VDD V 0.4 0.6 -10 (Notes 3, 4) V 0.8 V +10 A 10 pF 2 A Active temp conversions 1000 Communication only 100 A AC Electrical Characteristics (1.7V VDD 3.7V, TA = -55C to +125C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS Resolution MIN 9 9-bit conversions Temperature Conversion Time tCONVT SCL Frequency fSCL Bus Free Time Between a STOP and START Condition tBUF START and Repeated START Hold Time from Falling SCL www.maximintegrated.com tHD:STA TYP MAX UNITS 12 Bits 25 10-bit conversions 50 11-bit conversions 100 12-bit conversions 200 400 ms kHz (Note 5) 1.3 s (Notes 5, 6) 600 ns Maxim Integrated 2 DS75LV Digital Thermometer and Thermostat AC Electrical Characteristics (continued) (1.7V VDD 3.7V, TA = -55C to +125C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS tLOW (Note 5) 1.3 s tHIGH (Note 5) 0.6 s Repeated START Condition Setup Time to Rising SCL tSU:STA (Note 5) 600 ns Data-Out Hold Time from Falling SCL tHD:DAT (Notes 5, 7) Data-In Setup Time to Rising SCL tSU:DAT (Note 5) Rise Time of SDA and SCL (Receive) tR (Note 5) 1000 ns Fall Time of SDA and SCL (Receive) tF (Note 5) 300 ns 50 ns Low Period of SCL High Period of SCL Spike Suppression Filter Time (Deglitch Filter) STOP Setup Time to Rising SCL Capacitive Load for Each Bus Line Input Capacitance Serial Interface Reset Time Note 1: Note Note Note Note Note Note 2: 3: 4: 5: 6: 7: Note 8: tSS tSU:STO 0 0.9 100 ns 0 (Note 5) 600 ns CB CI tTIMEOUT 400 pF 325 ms 5 SDA time low (Note 8) 75 s pF Internal heating caused by OS loading causes the DS75LV to read approximately 0.5C higher if OS is sinking the max rated current. All voltages are referenced to ground. IDD specified with VDD at 3.0V and SDA, SCL = 3.0V, 0C to +70C. IDD specified with OS pin open. See Figure 2 for timing diagram. All timing is referenced to 0.9 x VDD and 0.1 x VDD. After this period, the first clock pulse is generated. The DS75LV provides an internal hold time of at least 75ns on the SDA signal to bridge the undefined region of SCL's falling edge. This timeout applies only when the DS75LV is holding SDA low. Other devices can hold SDA low indefinitely and the DS75LV does not reset. www.maximintegrated.com Maxim Integrated 3 DS75LV Digital Thermometer and Thermostat Pin Description PIN NAME FUNCTION 1 SDA Data Input/Output. For 2-wire serial communication port. Open drain. 2 SCL Clock Input. 2-wire serial communication port. 3 OS Thermostat Output. Open drain. 4 GND 5 A2 Address Input 6 A1 Address Input 7 A0 Address Input 8 VDD Ground Supply Voltage. +1.7V to +3.7V supply pin. PRECISION REFERENCE DIGITAL DECIMATOR OVERSAMPLING MODULATOR VDD CONFIGURATION REGISTER SCL SDA ADDRESS AND I/O CONTROL A0 A1 A2 TEMPERATURE REGISTER OS THERMOSTAT COMPARATOR TOS AND THYST REGISTERS GND RP DS75LV Figure 1. Block Diagram SDA tF tLOW tSU;DAT tR tF tHD;STA tSP tR tBUF SCL tHD;STA S tHD;DAT tSU;STA tSU;STO Sr P S Figure 2. Timing Diagram www.maximintegrated.com Maxim Integrated 4 DS75LV Digital Thermometer and Thermostat Detailed Description Measuring Temperature The DS75LV measures temperature using a bandgap temperature sensing architecture. An on-board delta-sigma analog-to-digital converter (ADC) converts the measured temperature to a digital value that is calibrated in degrees centigrade; for Fahrenheit applications a lookup table or conversion routine must be used. The DS75LV is factorycalibrated and requires no external components to measure temperature. At power-up the DS75LV immediately begins converting temperature to a digital value. The resolution of the digital output data is user-configurable to 9, 10, 11, or 12 bits, corresponding to temperature increments of 0.5C, 0.25C, 0.125C, and 0.0625C, respectively, with 9-bit default resolution at power-up. The resolution is controlled via the R0 and R1 bits in the configuration register as explained in the Configuration Register section. Note that the conversion time doubles for each additional bit of resolution. After each temperature measurement and analog-to-digital conversion, the DS75LV stores the temperature as a 16-bit two's complement number in the 2-byte temperature register (see Figure 3). The sign bit (S) indicates if the temperature is positive or negative: for positive numbers S = 0 and for negative numbers S = 1. The most recently converted digital measurement can be read from the temperature register at any time. Since temperature conversions are performed in the background, reading the temperature register does not affect the operation in progress. MS Byte LS Byte Bits 3 through 0 of the temperature register are hardwired to 0. When the DS75LV is configured for 12-bit resolution, the 12 MSbs (bits 15 through 4) of the temperature register contain temperature data. For 11-bit resolution, the 11 MSbs (bits 15 through 5) of the temperature register contain data, and bit 4 reads out as 0. Likewise, for 10-bit resolution, the 10 MSbs (bits 15 through 6) contain data, and for 9-bit the 9 MSbs (bits 15 through 7) contain data, and all unused LSbs contain 0s. Table 1 gives examples of 12-bit resolution digital output data and the corresponding temperatures. Table 1. 12-Bit Resolution Temperature/ Data Relationship TEMPERATURE (C) DIGITAL OUTPUT (BINARY) DIGITAL OUTPUT (HEX) +125 0111 1101 0000 0000 7D00h +25.0625 0001 1001 0001 0000 1910h +10.125 0000 1010 0010 0000 0A20h +0.5 0000 0000 1000 0000 0080h 0 0000 0000 0000 0000 0000h -0.5 1111 1111 1000 0000 FF80h -10.125 1111 0101 1110 0000 F5E0h -25.0625 1110 0110 1111 0000 E6F0h -55 1100 1001 0000 0000 C900h bit 15 bit 14 bit 13 bit 12 bit 11 bit 10 bit 9 bit 8 S 26 25 24 23 22 21 20 bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 2-1 2-2 2-3 2-4 0 0 0 0 Figure 3. Temperature, TOS, and THYST Register Format www.maximintegrated.com Maxim Integrated 5 DS75LV Shutdown Mode For power-sensitive applications, the DS75LV offers a low-power shutdown mode. The SD bit in the configuration register controls shutdown mode. When SD is changed to 1, the conversion in progress is completed and the result stored in the temperature register after which the DS75LV goes into a low-power standby state. The OS output is cleared if the thermostat is operating in interrupt mode and OS remains unchanged in comparator mode. The 2-wire interface remains operational in shutdown mode, and writing a 0 to the SD bit returns the DS75LV to normal operation. Thermostat The DS75LV thermostat has two operating modes, comparator mode and interrupt mode, which activate and deactivate the open-drain thermostat output (OS) based on user-programmable trip-points (TOS and THYST). The DS75LV powers up with the thermostat in comparator mode, active-low OS polarity, over-temperature trip-point (TOS) register set to 80C, and the hysteresis trip-point (THYST) register set to 75C. If these power-up settings are compatible with the application, the DS75LV can be used as a standalone thermostat (i.e., no 2-wire communication required). If interrupt mode operation, activehigh OS polarity or different TOS and THYST values are desired, they must be programmed after power-up, so standalone operation is not possible. In both operating modes, the user can program the thermostat fault tolerance, which sets how many consecutive temperature readings (1, 2, 4, or 6) must fall outside of the thermostat limits before the thermostat output is triggered. The fault tolerance is set by the F1 and F0 bits in the configuration register. At power-up the fault tolerance is set to 1. The data format of the TOS and THYST registers is identical to that of the temperature register (see Figure 3), i.e., a 2-byte two's complement representation of the trip-point temperature in degrees centigrade with bits 3 through 0 hardwired to 0. After every temperature conversion, the measurement is compared to the values stored in the TOS www.maximintegrated.com Digital Thermometer and Thermostat and THYST registers. The OS output is updated based on the result of the comparison and the operating mode of the IC. The number of TOS and THYST bits used during the thermostat comparison is equal to the conversion resolution set by the R1 and R0 bits in the configuration register. For example, if the resolution is 9 bits, only the 9 MSbs of TOS and THYST are used by the thermostat comparator. The active state of the OS output can be changed via the POL bit in the configuration register. The power-up default is active low. If the user does not wish to use the thermostat capabilities of the DS75LV, the OS output should be left floating. Note that if the thermostat is not used, the TOS and THYST registers can be used for general storage of system data. Comparator Mode: When the thermostat is in comparator mode, OS can be programmed to operate with any amount of hysteresis. The OS output becomes active when the measured temperature exceeds the TOS value a consecutive number of times as defined by the F1 and F0 fault tolerance (FT) bits in the configuration register. OS then stays active until the first time the temperature falls below the value stored in THYST. Putting the device into shutdown mode does not clear OS in comparator mode. Thermostat comparator mode operation with FT = 2 is illustrated in Figure 4. Interrupt Mode: In interrupt mode, the OS output first becomes active when the measured temperature exceeds the TOS value a consecutive number of times equal to the FT value in the configuration register. Once activated, OS can only be cleared by either putting the DS75LV into shutdown mode or by reading from any register (temperature, configuration, TOS, or THYST ) on the device. Once OS has been deactivated, it is only reactivated when the measured temperature falls below the THYST value a consecutive number of times equal to the FT value. Again, OS can only be cleared by putting the device into shutdown mode or reading any register. Thus, this interrupt/ clear process is cyclical between TOS and THYST events (i.e, TOS, clear, THYST, clear, TOS, clear, THYST, clear, etc.). Thermostat interrupt mode operation with FT = 2 is illustrated in Figure 4. Maxim Integrated 6 DS75LV Digital Thermometer and Thermostat Configuration Register The configuration register allows the user to program various DS75LV options such as conversion resolution, thermostat fault tolerance, thermostat polarity, thermostat operating mode, and shutdown mode. The configuration IN THIS EXAMPLE THE DS75LV IS CONFIGURED TO HAVE A FAULT TOLERANCE OF 2. register is arranged as shown in Figure 5 and detailed descriptions of each bit are provided in Table 2. The user has read/write access to all bits in the configuration register except the MSb, which is a reserved read-only bit. The entire register is volatile, and thus powers up in its default state. TOS TEMPERATURE THYST INACTIVE OS OUTPUT - COMPARATOR MODE ACTIVE INACTIVE OS OUTPUT - INTERRUPT MODE ACTIVE ASSUMES A READ HAS OCCURRED CONVERSIONS Figure 4. OS Output Operation Example MSb BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 LSb 0 R1 R0 F1 F0 POL TM SD Figure 5. Configuration Register www.maximintegrated.com Maxim Integrated 7 DS75LV Digital Thermometer and Thermostat Table 2. Configuration Register Bit Descriptions BIT NAME FUNCTION 0 Reserved Power-up state = 0 The master can write to this bit, but it will always read out as a 0. R1 Conversion Resolution Bit 1 Power-up state = 0 Sets conversion resolution (see Table 3) R0 Conversion Resolution Bit 0 Power-up state = 0 Sets conversion resolution (see Table 3) F1 Thermostat Fault Tolerance Bit 1 Power-up state = 0 Sets the thermostat fault tolerance (see Table 4). F0 Thermostat Fault Tolerance Bit 0 Power-up state = 0 Sets the thermostat fault tolerance (see Table 4). POL Thermostat Output (OS) Polarity Power-up state = 0 POL = 0 -- OS is active low. POL = 1 -- OS is active high. TM Thermostat Operating Mode Power-up state = 0 TM = 0 -- Comparator mode TM = 1 -- Interrupt mode See the Thermostat section for a detailed description of these modes. SD Shutdown Power-up state = 0 SD = 0 -- Active conversion and thermostat operation. SD = 1 -- Shutdown mode. See the Shutdown Mode section for a detailed description of this mode. Table 3. Resolution Configuration Table 5. Register Pointer Definition REGISTER P1 P0 0 0 R1 R0 THERMOMETER RESOLUTION MAX CONVERSION TIME (ms) Temperature 0 0 9-bit 25 Configuration 0 1 0 1 10-bit 50 1 0 1 0 11-bit 100 THYST 1 1 12-bit 200 TOS 1 1 Table 4. Fault Tolerance Configuration F1 F0 CONSECUTIVE OUT-OF-LIMITS CONVERSIONS TO TRIGGER OS 0 0 1 0 1 2 1 0 4 1 1 6 www.maximintegrated.com Maxim Integrated 8 DS75LV Register Pointer The four DS75LV registers each have a unique 2-bit pointer designation, which is defined in Table 5. When reading from or writing to the DS75LV, the user must "point" the DS75LV to the register that is to be accessed. When reading from the DS75LV, once the pointer is set, it remains pointed at the same register until it is changed. For example, if the user desires to perform consecutive reads from the temperature register, then the pointer only has to be set to the temperature register one time, after which all reads are automatically from the temperature register until the pointer value is changed. When writing to the DS75LV, the pointer value must be refreshed each time a write is performed, even if the same register is being written to twice in a row. At power-up, the pointer defaults to the temperature register location. The temperature register can be read immediately without resetting the pointer. Changes to the pointer setting are accomplished as described in the 2-Wire Serial Data Bus section of this data sheet. 2-Wire Serial Data Bus The DS75LV communicates over a standard bidirectional 2-wire serial data bus that consists of a serial clock (SCL) signal and serial data (SDA) signal. The device interfaces to the bus via the SCL input pin and open-drain SDA I/O pin. All communication is MSb first. The following terminology is used to describe 2-wire communication: Master Device: Microprocessor/microcontroller that controls the slave devices on the bus. The master device generates the SCL signal and START and STOP conditions. Slave: All devices on the bus other than the master. The DS75LV always functions as a slave. Bus Idle or Not Busy: Both SDA and SCL remain high. SDA is held high by a pullup resistor when the bus is idle, and SCL must either be forced high by the master (if the SCL output is push-pull) or pulled high by a pullup resistor (if the SCL output is open-drain). Transmitter: A device (master or slave) that is sending data on the bus. www.maximintegrated.com Digital Thermometer and Thermostat Receiver: A device (master or slave) that is receiving data from the bus. START Condition: Signal generated by the master to indicate the beginning of a data transfer on the bus. The master generates a START condition by pulling SDA from high to low while SCL is high (see Figure 6). A "repeated" START is sometimes used at the end of a data transfer (instead of a STOP) to indicate that the master will perform another operation. STOP Condition: Signal generated by the master to indicate the end of a data transfer on the bus. The master generates a STOP condition by transitioning SDA from low to high while SCL is high (see Figure 6). After the STOP is issued, the master releases the bus to its idle state. Acknowledge (ACK): When a device (either master or slave) is acting as a receiver, it must generate an acknowledge (ACK) on the SDA line after receiving every byte of data. The receiving device performs an ACK by pulling the SDA line low for an entire SCL period (see Figure 6). During the ACK clock cycle, the transmitting device must release SDA. A variation on the ACK signal is the "not acknowledge" (NACK). When the master device is acting as a receiver, it uses a NACK instead of an ACK after the last data byte to indicate that it is finished receiving data. The master indicates a NACK by leaving the SDA line high during the ACK clock cycle. Slave Address: Every slave device on the bus has a unique 7-bit address that allows the master to access that device. The DS75LV's 7-bit bus address is 1 0 0 1 A2 A1 A0, where A2, A1, and A0 are user-selectable via the corresponding input pins. The three address pins allow up to eight DS75LVs to be multi-dropped on the same bus. Address Byte: The control byte is transmitted by the master and consists of the 7-bit slave address plus a read/write (R/W) bit (see Figure 7). If the master is going to read data from the slave device then R/W = 1, and if the master is going to write data to the slave device then R/W = 0. Pointer Byte: The pointer byte is used by the master to tell the DS75LV which register is going to be accessed during communication. The six MSbs of the pointer byte (see Figure 8) are always 0 and the two LSbs correspond to the desired register as shown in Table 5. Maxim Integrated 9 DS75LV Digital Thermometer and Thermostat ... SDA ... SCL START CONDITION STOP CONDITION ACK (OR NACK) FROM RECEIVER Figure 6. START, STOP, and ACK Signals BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 1 0 0 1 A2 A1 A0 R/W BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 0 0 0 0 0 0 P1 P0 Figure 7. Address Byte Figure 8. Pointer Byte General 2-Wire Information All data is transmitted MSb first over the 2-wire bus. One bit of data is transmitted on the 2-wire bus each SCL period. A pullup resistor is required on the SDA line and, when the bus is idle, both SDA and SCL must remain in a logic-high state. All bus communication must be initiated with a START condition and terminated with a STOP condition. During a START or STOP is the only time SDA is allowed to change states while SCL is high. At all other times, changes on the SDA line can only occur when SCL is low: SDA must remain stable when SCL is high. After every 8-bit (1-byte) transfer, the receiving device must answer with an ACK (or NACK), which takes one SCL period. Therefore, nine clocks are required for every one-byte data transfer. www.maximintegrated.com Writing to the DS75LV: To write to the DS75LV, the master must generate a START followed by an address byte containing the DS75LV bus address. The value of the R/W bit must be a 0, which indicates that a write is about to take place. The DS75LV responds with an ACK after receiving the address byte. The master then sends a pointer byte which tells the DS75LV which register is being written to. The DS75LV again responds with an ACK after receiving the pointer byte. Following this ACK the master device must immediately begin transmitting data to the DS75LV. When writing to the configuration register, the master must send one byte of data (see Figure 9b), and when writing to the TOS or THYST registers the master must send two bytes of data (see Figure 9c). After receiving each data byte, the DS75LV responds with an ACK, and the transaction is finished with a STOP from the master. Maxim Integrated 10 DS75LV Software POR: The soft power-on reset (POR) command is 54h. The master sends a START followed by an address byte containing the DS75LV bus address. The R/W bit must be a 0. The DS75LV responds with an ACK. If the next byte is a 0x54, the DS75LV resets as if power had been cycled. No ACK is sent by the IC after the POR command is received. Reading from the DS75LV: When reading from the DS75LV, if the pointer was already pointed to the desired register during a previous transaction, the read can be performed immediately without changing the pointer setting. In this case the master sends a START followed by an address byte containing the DS75LV bus address. The R/W bit must be a 1, which tells the DS75LV that a read is being performed. After the DS75LV sends an ACK in response to the address byte, the DS75LV begins transmitting the requested data on the next clock cycle. When reading from the configuration register, the DS75LV transmits one byte of data, after which the master must respond with a NACK followed by a STOP (see Figure 9e). For two-byte reads (i.e., from the Temperature, TOS or THYST register), the DS75LV transmits two bytes of data, and the master must respond to the first data byte with an ACK and to the second byte with a NACK followed by a STOP (see Figure 9a). If only the most significant byte of data is needed, the master can issue www.maximintegrated.com Digital Thermometer and Thermostat a NACK followed by a STOP after reading the first data byte in which case the transaction is the same as for a read from the configuration register. If the pointer is not already pointing to the desired register, the pointer must first be updated as shown in Figure 9d, which shows a pointer update followed by a single-byte read. The value of the R/W bit in the initial address byte is a 0 ("write") since the master is going to write a pointer byte to the DS75LV. After the DS75LV responds to the address byte with an ACK, the master sends a pointer byte that corresponds to the desired register. The master must then perform a repeated start followed by a standard one or two byte read sequence (with R/W =1) as described in the previous paragraph. Bus Timeout: The DS75LV has a bus timeout feature that prevents communication errors from leaving the IC in a state where SDA is held low disrupting other devices on the bus. If the DS75LV holds the SDA line low for a period of tTIMEOUT, its bus interface automatically resets and release the SDA line. Bus communication frequency must be fast enough to prevent a reset during normal operation. The bus timeout feature only applies to when the DS75LV is holding SDA low. Other devices can hold SDA low for an undefined period without causing the interface to reset. Maxim Integrated 11 DS75LV Digital Thermometer and Thermostat A) READ 2 BYTES FROM THE TEMPERATURE, T OS, OR THYST REGISTER (CURRENT POINTER LOCATION) SCL SDA S 1 0 START 0 1 A2 A1 A0 R ADDRESS BYTE A D7 D6 D5 D4 D3 D2 D1 D0 A D7 D6 D5 D4 D3 D2 D1 D0 N ACK (DS75LV) MS DATA BYTE (FROM DS75LV) ACK (MASTER) LS DATA BYTE (FROM DS75LV) P NACK STOP (MASTER) B) WRITE TO THE CONFIGURATION REGISTER SCL SDA S 1 0 START 0 1 A2 A1 A0 W ADDRESS BYTE A 0 0 ACK (DS75LV) 0 0 0 0 POINTER BYTE 0 1 A D7 D6 D5 D4 D3 D2 D1 D0 A ACK (DS75LV) DATA BYTE (FROM MASTER) P ACK STOP (DS75LV) C) WRITE TO THE TOS OR THYST REGISTER SCL SDA S 1 0 START 0 1 A2 A1 A0 W ADDRESS BYTE A 0 0 ACK (DS75LV) 0 0 0 0 P1 P0 POINTER BYTE A D7 D6 D5 D4 D3 D2 D1 D0 A D7 D6 D5 D4 D3 D2 D1 ACK (DS75LV) MS DATA BYTE (FROM MASTER) ACK (DS75LV) LS DATA BYTE (FROM MASTER) A P ACK STOP (DS75LV) D) READ SINGLE BYTE (NEW POINTER LOCATION) SCL SDA S 1 0 START 0 1 A2 A1 A0 W ADDRESS BYTE A 0 ACK (DS75LV) 0 0 0 0 0 P1 P0 A POINTER BYTE ACK (DS75LV) S 1 REPEAT START 0 0 1 A2 A1 A0 R ADDRESS BYTE A D7 D6 D5 D4 D3 D2 D1 D0 N ACK (DS75LV) DATA BYTE (FROM DS75LV) P NACK STOP (MASTER) E) READ FROM THE CONFIGURATION REGISTER (CURRENT POINTER LOCATION) SCL SDA S 1 START 0 0 1 A2 A1 A0 R ADDRESS BYTE A D7 D6 D5 D4 D3 D2 D1 D0 N ACK (DS75LV) DATA BYTE (FROM DS75LV) P NACK STOP (MASTER) Figure 9. 2-Wire Interface Timing www.maximintegrated.com Maxim Integrated 12 DS75LV Digital Thermometer and Thermostat Ordering Information PART TEMP RANGE TOP MARK PIN-PACKAGE DS75LVS+ -55C to +125C DS75L* 8 SO DS75LVS+T&R -55C to +125C DS75L* 8 SO DS75LVU+ -55C to +125C DS75L 8 SOP (MAX(R)) DS75LVU+T&R -55C to +125C DS75L 8 SOP (MAX) +Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. *A "+" symbol is also marked on the package near the pin 1 indicator. Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 SO S8+2 21-0141 90-0096 8 MAX U8+1 21-0036 90-0092 MAX is a registered trademark of Maxim Integrated Products, Inc. www.maximintegrated.com Maxim Integrated 13 DS75LV Digital Thermometer and Thermostat Revision History REVISION NUMBER REVISION DATE PAGES CHANGED 0 5/06 Initial release -- 1 11/06 Changed the max conversion time for R1 and R0 in Table 4 8 2 12/14 Updated Benefits and Features section 3 4/15 Revised Electrical Characteristics, Table 3, and Ordering Information 4 3/16 Updated rise and fall time of SCL and SDA in Electrical Characteristics table 3 5 11/16 Added Thermistor Error typical specification 2 DESCRIPTION 1 2, 3, 8, 13 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated's website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. (c) 2016 Maxim Integrated Products, Inc. 14 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: DS75LVS+T&R DS75LVU+T&R DS75LVS+ DS75LVU+