STTS751-1WB3F

STTS751 2.25 V low-voltage local digital temperature sensor Datasheet - production data  One-shot mode for power saving  Fast conversion time 21 ms (typ) 10-bit  Pull-up resistor value allows single pin to select one of four slave addresses  Supports 400 kHz serial clock UDFN-6L Feature  SMBus 2.0 compatible – SMBus ALERT (ARA) support – SMBus timeout  Operating voltage 2.25 V to 3.6 V  RoHS/green  Operating temperature –40 °C to +125 °C  Programmable – 10 different conversion rates 0.0625 to 32 conversions/sec. 1 conversion/sec. - default – 4 different resolutions 9-bit (0.5 °C/LSB) to12-bit (0.0625 °C/LSB) 10-bit (0.25 °C/LSB) - default  Low supply current – 50 μA (typ) for 8 conversions/sec. – 20 μA (typ) for 1 conversion/sec. – 3 μA (typ) standby Applications  Solid state drives  Portable electronics  Notebook computers  Smart batteries  Servers  Telecom  Accuracy – ±0.5 °C (typ) 0 °C to +85 °C – ±0.5 °C (typ) –40 °C to +125 °C Table 1. Device summary Order code STTS751-0DP3F STTS751-1DP3F Pull-up resistor value SMBus address 7.5 K ±5% 1001 000 b 12 K ±5% 1001 001 b 20 K ±5% 0111 000 b 33 K ±5% 0111 001 b 7.5 K ±5% 1001 010 b 12 K ±5% 1001 011 b 20 K ±5% 0111 010 b 33 K ±5% 0111 011 b May 2019 This is information on a product in full production. DocID16483 Rev 7 Comments Address selection via resistor pull-up on Addr/Therm pin Address selection via resistor pull-up on Addr/Therm pin 1/35 www.st.com Contents STTS751 Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3 SMBus interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4 5 2/35 3.1 SMBus protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.2 WRITE byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.3 READ byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.4 SEND byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.5 RECEIVE byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.6 SMBus addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.7 SMBus timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.8 Alert response address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 STTS751 register summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4.1 STTS751 register formats and details . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.2 Temperature register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.3 Temperature limit register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.4 Temperature examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.5 Status register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.6 Configuration register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.7 Conversion rate register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.8 One-shot register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.9 Therm limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.10 Therm hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.11 SMBus timeout register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.12 STTS751 product ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.13 STTS751 manufacturer’s ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.14 STTS751 revision ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 EVENT output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 DocID16483 Rev 7 STTS751 Contents 6 Addr/Therm output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 7 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 8 DC and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 9 Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 9.1 UDFN-6L package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 9.2 Packing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 10 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 11 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 DocID16483 Rev 7 3/35 35 List of tables STTS751 List of tables Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Table 8. Table 9. Table 10. Table 11. Table 12. Table 13. Table 14. Table 15. Table 16. Table 17. Table 18. Table 19. Table 20. Table 21. Table 22. Table 23. Table 24. Table 25. Table 26. Table 27. Table 28. Table 29. Table 30. Table 31. Table 32. Table 33. Table 34. 4/35 Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Pin descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 SMBus WRITE byte protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 SMBus READ byte protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 SMBus SEND byte protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 SMBus RECEIVE byte protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 SMBus protocol response to ARA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Registers/pointers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Pointer register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Temperature register (two’s complement) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Temperature limit register (two’s complement format) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Temperature examples (two’s complement format) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Status register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Configuration register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Conversion resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Conversion rate register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Conversion rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 One-shot register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Therm limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Therm hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 SMBus timeout register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Product ID register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Manufacturer’s ID register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Revision ID register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 DC and AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 UDFN-6L (2 mm x 2 mm x 0.5 mm) package mechanical data . . . . . . . . . . . . . . . . . . . . . 29 Carrier tape dimensions for UDFN-6L package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Reel dimensions for 8 mm carrier tape - UDFN-6L package . . . . . . . . . . . . . . . . . . . . . . . 32 Ordering information scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Document revision history. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 DocID16483 Rev 7 STTS751 List of figures List of figures Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Application hardware hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 SMBus timing diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 EVENT output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Therm output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 AC measurement I/O waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 UDFN-6L (2 mm x 2 mm x 0.5 mm) package outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 UDFN-6L package footprint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Carrier tape for UDFN-6L package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Reel schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 DocID16483 Rev 7 5/35 35 Description 1 STTS751 Description The STTS751 is a digital temperature sensor which communicates over a 2-wire SMBus 2.0 compatible bus. The temperature is measured with a user-configurable resolution between 9 and 12 bits. At 9 bits, the smallest step size is 0.5 °C, and at 12 bits, it is 0.0625 °C. At the default resolution (10 bits, 0.25 °C/LSB), the conversion time is nominally 21 milliseconds. The open-drain EVENT output is used to indicate an alarm condition in which the measured temperature has exceeded the user-programmed high limit or fallen below the low limit. When the EVENT pin is asserted, the host can respond using the SMBus Alert Response Address (ARA) protocol to which the STTS751 will respond by sending its slave address. The STTS751 is a 6-pin device that supports user-configurable slave addresses. Via the pull-up resistor on the Addr/Therm pin, one of four different slave addresses can be specified. Two order numbers (STTS751-0 and STTS751-1) provide two different sets of slave addresses bringing the total available to eight. Thus, up to eight devices can share the same 2-wire SMBus without ambiguity, thereby allowing monitoring of multiple temperature zones in an application. The two-wire interface can support transfer rates up to 400 kHz. Figure 1. Logic diagram VDD (1) EVENT SDA STTS751-0 STTS751-1 Addr/Therm SCL GND AM03028v1 1. This pin may not float. Table 2. Signal names 6/35 Symbol Type Description Addr/Therm Output Address selection pin / thermal status pin EVENT Output Event (alert) output SDA I/O SCL Input VDD Power Device power supply GND Ground Device ground SMBus interface data I/O SMBus interface clock input DocID16483 Rev 7 STTS751 Description Figure 2. Pinout SCL EVENT VDD 1 6 SDA 2 5 GND 3 4 Addr/Therm AM03029v1 Table 3. Pin descriptions Pin Name 1 SCL 2 EVENT 3 VDD 4 Description SMBus clock Open-drain interrupt output. Output supports the SMBus Alert (ARA). Note: This pin may not float. Power supply VDD Open-drain output that can be used to turn on/off a fan or throttle a CPU clock in the event of an overtemperature condition. The pin at power-up determines the SMBus slave address according to the pull-up resistor value as shown in Table 1. Addr/Therm This pin must have a pull-up resistor connected to the same voltage as VDD or tied to GND (pin cannot float). Total capacitance on this pin must be high limit). THIGH is cleared when the status register is read, provided the condition no longer exists. TLOW: [5] Bit = 1 indicates the is at or below the low limit (TA low limit). TLOW is cleared when the status register is read, provided the condition no longer exists. RFU: [4:1] Not used - reserved. THRM: [0] Bit = 1 indicates the measured temperature has crossed the Therm limit. The THRM bit will go low when the temperature falls below the Therm limit minus the Therm Hysteresis. When the THRM bit is high, the Addr/Therm output will be asserted low. 16/35 DocID16483 Rev 7 STTS751 4.6 STTS751 register summary Configuration register The STTS751 configuration register is read/write and controls the functionality of temperature measurements. It is located at address 03h. The configuration register bits function as described below. Table 15. Configuration register ADDR (hex) R/W Register 03 R/W Configuration b7 b6 MASK1 RUN/STOP b5 b4 b3 b2 b1 b0 Power-up default (hex) 0 RFU Tres1 Tres0 RFU RFU 00 Description MASK1: [bit 7] 0: EVENT is enabled. Any out-of-limit condition asserts the EVENT pin (active low). 1: EVENT is disabled. RUN/STOP: [bit 6] 0: Device is running in continuous conversion mode. 1: Device is in standby mode drawing minimum power. The RUN/STOP bit controls temperature conversions by the ADC. When this bit is 0, the ADC converts temperatures in continuous mode, at a rate as selected by the Conversion Rate register (Section 4.7). When the RUN/STOP bit is 1, the ADC will be in standby mode, thus reducing current supply significantly. Note: The device can still be accessed via the SMBus while in standby mode. When RUN/STOP is 1 and the one-shot register is written to, the ADC will execute a temperature measurement and then return to standby mode. [bit 5]: This bit must always be 0. RFU: [bit 4] Not used - reserved. DocID16483 Rev 7 17/35 35 STTS751 register summary STTS751 Tres1:Tres0 [bits 3 and 2] These bits select one of the four programmable resolutions for temperature data on the STTS751 providing resolutions down to 0.0625 °C/LSB. The default resolution is 10 bits, 0.25 °C/LSB. Table 16. Conversion resolution Tres1:Tres0 Temperature resolution LSB step size (°C) 00 10 bits (default) 0.25 01 11 bits 0.125 11 12 bits 0.0625 10 9 bits 0.5 RFU [bits 1 and 0] Not used - reserved. 4.7 Conversion rate register The STTS751 conversion rate register is read/write and controls the number of times the temperature value will be updated each second. Table 17. Conversion rate register ADDR (hex) R/W Register b7 b6 b5 b4 04 R/W Conversion rate 0 0 0 0 b3 b2 b1 CONV[3:0] b0 Power-up default (hex) 04 (1/sec) The upper four bits of the register are reserved and default to 0 on power-up. The lower four bits control the conversion rate as shown in the table below. The power-up default is 1 conversion per second. The current draw is proportional to the conversion rate, and goes up at higher rates. 18/35 DocID16483 Rev 7 STTS751 STTS751 register summary Table 18. Conversion rates CONV[3:0] (hex) Conversions per second Typical current (μA) 0 0.0625 15 1 0.125 2 0.25 3 0.5 4 1 5 2 6 4 7 8 8 16 9 32 A-F reserved Comment 20 50 9, 10, or 11-bit resolutions only 125 9 or 10-bit resolutions only Note: The user must program the conversion rate and resolution bits (Tres1:Tres0 in the configuration register, address 03h) to be consistent with this table. For a sampling rate of 32 conversions per second, the maximum resolution is 10 bits. For 16 conversions per second, the maximum is 11 bits. 4.8 One-shot register The STTS751 can be configured to perform a single temperature conversion on demand. When the device is placed in standby mode (by setting RUN/STOP to 1 in the configuration register) a write to the one-shot register will invoke a temperature conversion. The device will set the busy bit while the conversion is in progress. The conversion is complete when the busy bit is cleared. The STTS751 returns to standby mode upon completion of the conversion. The one-shot register is write-only and is located at address 0Fh. The value written to invoke the one-shot conversion is a don't care. The device responds only to the write at address 0Fh and ignores the value written. Note: Writes to the one-shot register will be ignored when the STTS751 is in continuous conversion mode (ie. when RUN/STOP=0). Table 19. One-shot register ADDR (hex) R/W Register b7 b6 b5 b4 b3 b2 b1 b0 Power-up default (hex) 0F W One shot X X X X X X X X n/a DocID16483 Rev 7 19/35 35 STTS751 register summary 4.9 STTS751 Therm limit The Therm limit is a read/write register located at address 20h. The power-on default value is 85 °C (55h). The format is 8-bit, two's complement integer. This is the same format as the upper byte of the temperature register (Section 4.2: Temperature register format). Whenever the temperature exceeds the value of the therm limit, the Addr/Therm output will be asserted (low). See Section 6 for more information. Table 20. Therm limit ADDR (hex) R/W Register b7 b6 b5 b4 b3 b2 20 R/W Therm sign 64 °C 32 °C 16 °C 8 °C 4 °C 4.10 b1 b0 2 °C 1 °C Power-up default (hex) 55 (85 °C, dec) Therm hysteresis The Therm hysteresis values controls the hysteresis for Addr/Therm output. Once Therm output has asserted, it will not de-assert until the temperature has fallen below the respective therm limit minus the therm hysteresis value. See Section 5 for more information. The therm hysteresis register is read/write and is located at address 21h. The power-up default value is 10 °C (0Ah). The format is 8-bit, two's complement integer. Table 21. Therm hysteresis ADDR (hex) R/W Register b7 b6 b5 b4 b3 b2 21 R/W Therm hysteresis sign 64 °C 32 °C 16 °C 8 °C 4 °C 4.11 b1 b0 2 °C 1 °C Power-up default (hex) 0A (10 °C, dec) SMBus timeout register At power-up, the STTS751 is configured with an SMBus timeout of 25 to 35 milliseconds (tTIMEOUT). See Section 3.7 for more information. Table 22. SMBus timeout register ADDR (hex) R/W 22 R/W Register b7 SMBus timeout TIMEOUT b6 b5 b4 b3 b2 b1 b0 Power-up default (hex) 0 0 0 0 0 0 0 80 TIMEOUT: [bit 7] 1: SMBus timeout is enabled. Default condition. 0: SMBus timeout is disabled. [bits 6:0] Not used - reserved. 20/35 DocID16483 Rev 7 STTS751 STTS751 register summary 4.12 STTS751 product ID The two versions of the STTS751 as shown in Table 1 can be identified via the read-only Product ID register at address FDh. The STTS751-0 has a Product ID of 00h. The STTS751-1 has a Product ID of 01h. Table 23. Product ID register ADDR (hex) R/W Register FD R Product ID 4.13 b7 b6 b5 b4 b3 b2 b1 b0 hex 0 0 0 0 0 0 0 0 00: STTS751-0 0 0 0 0 0 0 0 1 01: STTS751-1 STTS751 manufacturer’s ID The read-only manufacturer's ID is located at address FEh. For the STTS751, the value is 53h. Table 24. Manufacturer’s ID register ADDR (hex) R/W Register b7 b6 b5 b4 b3 b2 b1 b0 hex FE R Mfg ID 0 1 0 1 0 0 1 1 53 4.14 STTS751 revision ID The STTS751 revision ID register pointer is read-only and can be accessed at address FFh. The value is formatted as an unsigned, 8-bit integer. Table 25. Revision ID register ADDR (hex) R/W Register b7 b6 b5 b4 b3 b2 b1 b0 FF R Revision ID 0 0 0 0 0 0 0 1 DocID16483 Rev 7 21/35 35 EVENT output 5 STTS751 EVENT output The STTS751 EVENT output is open drain and requires a pull-up resistor. The EVENT pin is asserted (low) whenever the temperature exceeds the high limit or is equal to or below the low limit. Once asserted, the output will remain asserted until the STTS751 receives an SMBus Alert Response Address (ARA) from the host and acknowledges with its slave address. The output will be deasserted when the ARA is acknowledged. If the triggering condition is still true, the output will be reasserted at the next temperature conversion. Figure 6 below shows how the EVENT output functions. Figure 6. EVENT output Temperature Temperature high limit Temperature low limit Time EVENT SMBus ARA acknowledged 22/35 DocID16483 Rev 7 AM03032v1 STTS751 6 Addr/Therm output Addr/Therm output The Addr/Therm pin functions normally as an output to alert the system of an over temperature condition. It is open drain and requires a pull-up resistor. During power-up, the pull-up value is sensed by the STTS751 to determine what its slave address will be as depicted in Table 1. The Therm output is asserted low whenever the temperature exceeds the Therm limit (address 20h). Only the upper 8 bits of the temperature register are used in the comparison with the Therm limit. Once asserted, Therm will remain asserted until temperature falls below the Therm limit minus the therm hysteresis value. For example, if the Therm limit is 25 °C, and the therm hysteresis value is 10 °C, the Therm output will assert when the temperature exceeds 25 °C. It will remain asserted until the temperature falls down to or below 15 °C (25 – 10). This pin can be used to control a fan or other failsafe device as shown in Figure 4 on page 8. Figure 7 below shows how the Therm output functions. Figure 7. Therm output Therm Hysteresis Temperature Therm limit Therm Limit minus Therm Hysteresis Time Addr/Therm AM03033v1 DocID16483 Rev 7 23/35 35 Maximum ratings 7 STTS751 Maximum ratings Stressing the device above the rating listed in the absolute maximum ratings table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the operating sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Table 26. Absolute maximum ratings Symbol TSTG TSLD(1) Parameter Storage temperature (VDD off) Lead solder temperature Value Unit –55 to 150 °C 260 °C –0.3 to VDD + 0.3 V VIO Input or output voltage VDD Supply voltage 5.0 V IO Output current 20 mA JA Thermal resistance (junction to ambient) 78 °C/W UDFN-6L 1. Reflow at peak temperature of 260 °C. The time above 255 °C must not exceed 30 seconds. 24/35 DocID16483 Rev 7 STTS751 8 DC and AC parameters DC and AC parameters This section summarizes the operating measurement conditions, and the DC and AC characteristics of the device. The parameters in the DC and AC characteristics tables that follow, are derived from tests performed under the measurement conditions summarized in Table 27: Operating and AC measurement conditions. Designers should check that the operating conditions in their circuit match the operating conditions when relying on the quoted parameters. Table 27. Operating and AC measurement conditions Parameter Conditions Unit VDD supply voltage - temperature sensor 2.25 to 3.6 V Ambient operating temperature (TA) –40 to +125 °C 5 ns Input pulse voltages 0.2 VDD to 0.8 VDD V Input and output timing reference voltages 0.3 VDD to 0.7 VDD V Input rise and fall times Figure 8. AC measurement I/O waveform Input and output timing reference levels Input levels 0.8 * VDD 0.7 * VDD 0.3 * VDD 0.2 * VDD AM04731v1 DocID16483 Rev 7 25/35 35 DC and AC parameters STTS751 Table 28. DC and AC characteristics Symbol Description VDD Supply voltage IDD ISB Test condition(1) Min Typ(2) 2.25 Operating current dependent upon conversion rate Max Unit 3.6 V 0.0625 conversions/second(3) 15 35 μA 1 conversion/second(3) 20 40 μA 8 conversions/second 50 85 μA 32 conversions/second 125 250 μA 3 8 μA 0 °C to 85 °C ±0.5 ±1.5 °C –40 °C to +125 °C ±0.5 ±2.5 °C 9-bit temperature data 0.5 °C/LSB 9 bits 10-bit temperature data (default) 0.25 °C/LSB 10 bits 0.125 °C/LSB 11 bits 0.0625 °C/LSB 12 bits Standby current Temperature measurement Accuracy(4) Resolution 2.25 V to 3.6 V STTS751 is programmable from 9 bits to 12 bits (0.5 °C/LSB to 0.0625 °C) 11-bit temperature data 12-bit temperature data tCONV Conversion time 9-bit 10.5 14 ms 10-bit (default) 21 28 ms 11-bit 42 56 ms 12-bit 84 112 ms VOL Low level output voltage Addr/Therm, EVENT IOL = 4 mA 0.4 V IOH High level output leakage current EVENT, SDA, Addr/Therm VOH = VDD 1 μA SMBus interface inputs (SDA, SCL) VIH Input logic high (SCL, SDA) 2.3 V VDD 3.6 V VIL Input logic low (SCL, SDA) 2.3 V VDD 3.6 V IHI Logical "1" input current 0 V VIN VDD ILI Logical "0" input current 0 V VIN  VDD CIN Input capacitance (SDA) ISINK SMBus output low sink current 26/35 0.7 x VDD V 0.3 x VDD V –1 1 μA –1 1 μA 5 SDA forced to 0.6 V DocID16483 Rev 7 6 pF mA STTS751 DC and AC parameters Table 28. DC and AC characteristics (continued) Symbol Description Test condition(1) Min VPV Pull-up supply voltage (open drain) (Addr/Therm) EVENT, SDA, SCL VPOR Power On Reset threshold (POR) - TS VDD falling edge tTIMEOUT SMBus timeout(5) tSP Spike suppression Pulse width of spikes that must be suppressed by the input filter Typ(2) Max Unit –0.3 3.6 V –0.3 5.5 V 1.75 V 25 Input filter on SCL and SDA 35 ms 50 ns 1. Valid for ambient operating temperature: TA = –40 to +125 °C; VDD = 2.25 V to 3.6 V (except where noted). 2. Typical numbers are for TA = +25 °C; VDD = 3.0 V 3. Not tested, guaranteed by design. 4. Accuracy measurements made at resolutions > 10 bits. 5. SMBus timeout min and max are valid for TA = –30 to +125 °C. Table 29. AC characteristics Symbol Description Min fSCL SMBus/I2C clock frequency 10 tHIGH Clock high period 600 ns tLOW Clock low period 1.3 μs tR Clock/data rise time 300 ns tF Clock/data fall time 300 ns tSU:DAT Data setup time 100 ns tHD:DI Data in hold time 0 ns tHD:DAT Data out hold time 300 ns tSU:STA Start condition setup time 600 ns tHD:STA Hold time after (repeated) start condition. After this period, the first clock cycle is generated. 600 ns tSU:STO Stop condition setup time 600 ns tBUF Bus free time between stop (P) and start (S) conditions 1.3 μs DocID16483 Rev 7 Typ Max Unit 400 kHz 27/35 35 Package information 9 STTS751 Package information In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ECOPACK is an ST trademark. 28/35 DocID16483 Rev 7 STTS751 9.1 Package information UDFN-6L package information Figure 9. UDFN-6L (2 mm x 2 mm x 0.5 mm) package outline 8187820_A Table 30. UDFN-6L (2 mm x 2 mm x 0.5 mm) package mechanical data mm inches Sym Min Typ Max Min Typ Max A 0.45 0.50 0.55 0.018 0.020 0.022 A1 0.00 0.05 0.000 A3 0.065 0.002 0.003 b 0.20 0.25 0.30 0.008 0.010 0.012 D 1.95 2.00 2.05 0.077 0.079 0.081 E 1.95 2.00 2.05 0.077 0.079 0.081 e L 0.65 0.50 0.60 0.026 0.70 DocID16483 Rev 7 0.020 0.024 0.028 29/35 35 Package information STTS751 Figure 10. UDFN-6L package footprint 8187820_A(LP) 30/35 DocID16483 Rev 7 STTS751 9.2 Package information Packing information Figure 11. Carrier tape for UDFN-6L package P0 E P2 D T A0 F TOP COVER TAPE W B0 P1 CENTER LINES OF CAVITY K0 USER DIRECTION OF FEED AM03073v1 Table 31. Carrier tape dimensions for UDFN-6L package Package W D E P0 P2 F A0 B0 K0 P1 T Unit UDFN-6L 8.00 0.30 1.50 +0.10/ –0.00 1.75 0.10 4.00 0.10 2.00 0.05 3.50 0.05 2.20 0.10 2.20 0.10 0.75 0.10 4.00 0.10 0.25 0.05 mm DocID16483 Rev 7 31/35 35 Package information STTS751 Figure 12. Reel schematic T 40mm min. Access hole At slot location B D C N A G measured Tape slot In core for Full radius Tape start 2.5mm min.width At hub AM04928v1 Table 32. Reel dimensions for 8 mm carrier tape - UDFN-6L package A B (max) (min) 180 mm (7 inch) 1.5 mm Note: 32/35 C 13 mm 0.2 mm D N (min) (min) 20.2 mm 60 mm G 8.4 mm + 2/–0 mm T (max) 14.4 mm The dimensions given in Table 32 incorporate tolerances that cover all variations on critical parameters. DocID16483 Rev 7 STTS751 10 Part numbering Part numbering Table 33. Ordering information scheme Example: STTS751-0 DP 3 F Device type STTS751-0 STTS751-1 Package DP = UDFN-6L Temperature range 3 = –40 °C to 125 °C Shipping method F = ECOPACK package, tape & reel For other options, or for more information on any aspect of this device, please contact the ST sales office nearest you. DocID16483 Rev 7 33/35 35 Revision history 11 STTS751 Revision history Table 34. Document revision history 34/35 Date Revision Changes 06-Nov-2009 1 Initial release. 21-Jan-2010 2 Updated Features; removed Therm2 throughout document (from Section 1, 2, 3.8, 4.6, 4.10, 5, Figure 1, 2, 3, 4, 6, Table 2, 3, 15, 28); updated Figure 3, Section 3.4, Section 4.6, Section 4.8, Section 4.10, Table 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25; added package footprints (Figure 11 and 12); minor textual changes. 12-May-2010 3 Updated Section 3.7, Section 40.11, Section 5; Figure 6, 7, 11, 12; Table 3, 9, 25, 28, 31; added tape and reel information (Figure 13, 14 and Table 32, 33); minor textual changes in title and document. 01-Jul-2010 4 Document status promoted to full datasheet; updated cover page; added footnote to Table 28; minor textual changes. 20-Jul-2010 5 Removed footnote from Table 28. 10-Sep-2018 6 Updated Accuracy in Features and Table 28: DC and AC characteristics 17-May-2019 7 Removed SOT23-6L package option DocID16483 Rev 7 STTS751 IMPORTANT NOTICE – PLEASE READ CAREFULLY STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. 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Information in this document supersedes and replaces information previously supplied in any prior versions of this document. © 2019 STMicroelectronics – All rights reserved DocID16483 Rev 7 35/35 35