STTS424BDN3F STMicroelectronics, STTS424BDN3F Datasheet

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Features ■ Temperature sensor compliant with JEDEC JC42.4 Temperature sensor ■ Temperature sensor resolution: 0.25°C (typ)/LSB ■ Temperature sensor accuracy: – ± 1°C from +75°C to +95°C – ± 2°C from +40°C to +125°C – ± 3°C from –40°C to ...

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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STTS424 5 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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List of tables List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STTS424 List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Description 1 Description The STTS424 is targeted for DIMM modules in mobile personal computing platforms (laptops), server memory modules, and other industrial applications. The thermal sensor (TS) in the STTS424 is fully compliant with the JEDEC specification which defines memory ...

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STTS424 2 Serial communications The STTS424 has a simple 2-wire SMBus/I allows the user to access the data in the temperature register at any time. It communicates via the serial interface with a master controller which operates at speeds of ...

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Serial communications Figure 2. TDFN8 connections (top view) 1. SDA and EVENT are open drain. Figure 3. Block diagram 8/ GND Temperature Sensor ADC Capability Register Configuration ...

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STTS424 2.2 Pin descriptions 2.2.1 A0, A1, A2 A2, A1, and A0 are selectable address pins for the 3 LSBs of the I They can be set to V 2.2.2 V (ground) SS This is the reference for the power ...

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Operation 3 Operation The STTS424 TS continuously monitors the ambient temperature and updates the temperature data registers at least eight times per second. Temperature data is latched internally by the device and may be read by software from the bus ...

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STTS424 2 Figure 4. SMBus/I C write to pointer register SCL SDA Start by Master 2 Figure 5. SMBus/I C write to pointer register, followed by a read data word 1 SCL SDA 0 0 Start by Master 1 SCL ...

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Operation Figure 6. SMBus/I SCL SDA SCL (continued) SDA (continued) 2 3.2 SMBus/I C slave sub-address decoding The physical address for the TS is binary RW, whereas A2, A1, and A0 are the ...

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STTS424 Figure 7. SMBus SCL SDA Table 2. AC SMBus and I Symbol t Bus free time between stop (P) and start (S) conditions BUF Hold time after (repeated) start condition. ...

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Temperature sensor registers 4 Temperature sensor registers The temperature sensor component is comprised of various user-programmable registers. These registers are required to write their corresponding addresses to the Pointer register. They can be accessed by writing to their respective addresses ...

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STTS424 Table 5. Pointer register select bits (type, width, and default values Name CAPA Thermal sensor capabilities CONF Configuration UPPER Alarm temperature upper boundary LOWER ...

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Temperature sensor registers Table 6. Capability register format Bit15 Bit14 RFU RFU Bit7 Bit6 RFU RFU C Table 7. Capability register bit definitions Bit Basic capability 0 – Alarm and critical trips turned OFF. – Alarm ...

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STTS424 4.2 Configuration register (read/write) The 16 bit Configuration register stores various configuration modes that are used to set up the sensor registers and configure according to application and JEDEC 42.4 requirements (see Table 8 on page 17 4.2.1 Event ...

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Temperature sensor registers Table 9. Configuration register bit definitions Bit Event mode 0 – Comparator output mode (this is the default) – Interrupt mode; when either of the lock bits is set, this bit cannot be ...

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STTS424 Figure 8. Hysteresis Below Window bit Above Window bit Value stored in the alarm temperature upper boundary trip register Value stored in the alarm temperature lower boundary trip register Hys ...

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Temperature sensor registers 4.2.5 Event output pin functionality The EVENT pin is an open drain output and requires a pull-up resistor to V motherboard or incorporated into the master controller. Figure 9 shows the defined outputs of the EVENT correspondent ...

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STTS424 Figure 9. Event output boundary timings T CRIT T UPPER LOWER Comparator Interrupt S/W Int. Clear Critical Table 11. Legend for Note Event output boundary conditions When ...

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Temperature sensor registers 4.3 Temperature register (read-only) This 16-bit, read-only register stores the temperature measured by the internal band gap TS as shown inTable requirement. When reading this register, the MSBs (bit 15 to bit 8) are read first, and ...

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STTS424 Table 13. Temperature register bit definitions Bit Below (temperature) alarm window 13 – Temperature is equal to or above the alarm window lower boundary temperature. – Temperature is below the alarm window. Above (temperature) alarm ...

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... Table 17. Critical temperature register format Bit Bit Bit 4.5 Manufacturer ID register (read-only) The manufacturer’s ID (programmed value 104Ah) in this register is the STMicroelectronics identification provided by the Peripheral Component Interconnect Special Interest Group (PCiSIG). Table 18. Manufacturer ID register format Bit15 Bit14 0 0 Bit7 Bit6 0 1 ...

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STTS424 4.6 Device ID and device revision ID register (read-only) The device IDs and device revision IDs are maintained in this register. The register format is shown in Table 19. The device IDs and device revision IDs are currently '0' ...

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... 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. Refer also to the STMicroelectronics SURE Program and other relevant quality documents. Table 20. ...

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STTS424 6 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 ...

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DC and AC parameters Table 22. DC and AC characteristics - temperature sensor Sym Description V Supply voltage DD V supply current, active DD temperature conversions I V supply current communication only (no conversions) Shutdown mode supply current, ...

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STTS424 7 Package mechanical data 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. ...

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Package mechanical data Figure 10. TDFN8 – 8-lead thin dual flat, no-lead ( mm) package outline (DN) Table 23. TDFN8 – 8-lead thin dual flat, no-lead ( mm) mechanical data (DN) Sym Min A ...

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STTS424 8 Part numbering Table 24. Ordering information scheme Example: Device type STTS424 Grade B: Maximum accuracy 75°C to 95°C = ± 1°C Package DN = TDFN8 ( mm) (0.80 mm max height) Temperature range 3 = ...

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Package marking information 9 Package marking information Figure 11. Device topside marking information (TDFN-8L) 1. TDFN package identifier DN = 0.80 mm (package height) 2. Traceability codes P = Plant code Y = Year WW = Work Week 32/36 424B ...

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STTS424 10 Landing pattern The landing pattern recommendations for the TDFN package (DN) are shown in The preferred implementation with wide corner pads enhances device centering during assembly, but a narrower option is defined for modules with tight routing requirements. ...

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Landing pattern Table 25 lists variations of landing pattern implementations, ranked as “preferred”, and minimum acceptable” based on the JEDEC proposal. Table 25. Parameters for landing pattern - TDFN package (DN) Parameter D2 Heat paddle width E2 Heat paddle height ...

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STTS424 11 Revision history Table 26. Document revision history Date 17-Apr-2007 09-May-2007 04-June-2007 02-Jul-2007 22-Oct-2008 01-Apr-2009 Revision 1 Initial release. 2 Updated Table 22, 23, and 24. 3 Updated Table 22. 4 Added POR threshold values ...

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... Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...