MAX6642 19-2920 Rev 3 10/09 1C, SMBus-Compatible Remote/Local Temperature Sensor with Overtemperature Alarm General Description Features The MAX6642 precise, two-channel digital temperature Dual Channel: Measures Remote and Local sensor accurately measures the temperature of its own Temperature die and a remote PN junction and reports the tempera- +0.25C Resolution ture data over a 2-wire serial interface. The remote PN High Accuracy 1C (max) (Remote) and junction is typically a substrate PNP transistor on the 2C (Local) from +60C to +100C die of a CPU, ASIC, GPU, or FPGA. The remote PN junction can also be a discrete diode-connected small- Measures Remote Temperature Up to +150C signal transistor. Programmable Overtemperature Alarm The 2-wire serial interface accepts standard system Temperature Thresholds management bus (SMBus), Write Byte, Read Byte, 2 SMBus/I C-Compatible Interface Send Byte, and Receive Byte commands to read the Tiny TDFN Package with Exposed Pad temperature data and to program the alarm thresholds. To enhance system reliability, the MAX6642 includes an Ordering Information SMBus timeout. The temperature data format is 10 bit with the least significant bit (LSB) corresponding to PART TEMP RANGE PIN-PACKAGE +0.25C. The ALERT output asserts when the local or MAX6642ATT90-T -40C to +125C 6 TDFN-EP* remote overtemperature thresholds are violated. A fault queue may be used to prevent the ALERT output from MAX6642ATT92-T -40C to +125C 6 TDFN-EP* setting until two consecutive faults have been detected. MAX6642ATT94-T -40C to +125C 6 TDFN-EP* Measurements can be done autonomously or in a sin- MAX6642ATT96-T -40C to +125C 6 TDFN-EP* gle-shot mode. MAX6642ATT98-T -40C to +125C 6 TDFN-EP* Remote accuracy is 1C maximum error between MAX6642ATT9A-T -40C to +125C 6 TDFN-EP* +60C and +100C. The MAX6642 operates from -40C MAX6642ATT9C-T -40C to +125C 6 TDFN-EP* to +125C, and measures remote temperatures MAX6642ATT9E-T -40C to +125C 6 TDFN-EP* between 0C and +150C. The MAX6642 is available in a 6-pin TDFN package with an exposed pad. T = Tape and reel. *EP = Exposed pad. Applications Pin Configuration and Functional Diagram appear at end of Desktop Computers data sheet. Notebook Computers Servers Typical Operating Circuit Thin Clients Test and Measurement 3.3V Workstations 0.1F 47 Graphic Cards Selector Guide 10k EACH V CC TOP PART MEASURED TEMP RANGE 2200pF MARK MAX6642 SDA DATA DXP MAX6642ATT90-T 0C to +150C AFC SCLK CLOCK MAX6642ATT92-T 0C to +150C AFD MAX6642ATT94-T 0C to +150C AFE ALERT INTERRUPT TO P MAX6642ATT96-T 0C to +150C AFF GND P MAX6642ATT98-T 0C to +150C AEW MAX6642ATT9A-T 0C to +150C AFG MAX6642ATT9C-T 0C to +150C AFH MAX6642ATT9E-T 0C to +150C AFI SMBus is a trademark of Intel Corp. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE1C, SMBus-Compatible Remote/Local Temperature Sensor with Overtemperature Alarm ABSOLUTE MAXIMUM RATINGS All Voltages Referenced to GND ESD Protection (all pins, Human Body Model)................2000V V ...........................................................................-0.3V to +6V Junction Temperature......................................................+150C CC DXP.............................................................-0.3V to (V + 0.3V) Operating Temperature Range .........................-40C to +125C CC SCLK, SDA, ALERT ..................................................-0.3V to +6V Storage Temperature Range .............................-65C to +150C SDA, ALERT Current...........................................-1mA to +50mA Lead Temperature (soldering, 10s) .................................+300C Continuous Power Dissipation (T = +70C) A 6-Pin TDFN (derate 24.4mW/C above +70C) .........1951mW 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. ELECTRICAL CHARACTERISTICS (V = +3.0V to +5.5V, T = -40C to +125C, unless otherwise specified. Typical values are at V = +3.3V and T = +25C.) (Note 1) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V 3.0 5.5 V CC 0.25 C Temperature Resolution 10 Bits T = +60C to +100C, RJ -1.0 +1.0 T = +25C to +85C A Remote Temperature Error V = 3.3V C CC T = 0C to +125C -3.0 +3.0 RJ T = +125C to +150C -3.5 +3.5 RJ T = +60C to +100C -2.0 +2.0 A Local Temperature Error V = 3.3V C CC T = 0C to +125C -3.0 +3.0 A Supply Sensitivity of Temperature 0.2 C/V Error Undervoltage Lockout Threshold UVLO Falling edge of V disables ADC 2.4 2.7 2.95 V CC Undervoltage Lockout Hysteresis 90 mV Power-On-Reset (POR) Threshold V falling edge 1.5 2.0 2.4 V CC POR Threshold Hysteresis 90 mV Standby Supply Current SMBus static 3 10 A Operating Current During conversion 0.5 1.0 mA Average Operating Current 260 A Conversion Time t From stop bit to conversion completion 106 125 143 ms CONV Conversion Rate f 8Hz CONV High level 80 100 120 Remote-Diode Source Current I A RJ Low level 8 10 12 ALERT V = 0.4V 1 OL Output-Low Sink Current mA V = 0.6V 4 OL Output-High Leakage Current V = V 1A OH CC 2 MAX6642