ADT7481 Dual Channel Temperature Sensor and Overtemperature Alarm The ADT7481 is a 3-channel digital thermometer and under/ over temperature alarm, intended for use in PCs and thermal management ADT7481 ADDRESS POINTER REGISTER CONVERSION RATE ON-CHIP ONE-SHOT REGISTER TEMPERATURE REGISTER SENSOR LOCAL TEMPERATURE LOCAL TEMPERATURE THERM LIMIT REGISTER VALUE REGISTER LOCAL TEMPERATURE D1+ 2 LOW LIMIT REGISTER 11-BIT A-TO-D D1 3 CONVERTER LOCAL TEMPERATURE ANALOG HIGH LIMIT REGISTER MUX RUN/STANDBY BUSY D2+ 7 REMOTE 1 & 2 TEMP. REMOTE 1 AND 2 TEMP D2 THERM LIMIT REG. 6 VALUE REGISTER REMOTE 1 & 2 TEMP. LOW LIMIT REGISTERS REMOTE 1 AND 2 TEMP REMOTE 1 & 2 TEMP. OFFSET REGISTER HIGH LIMIT REGISTERS CONFIGURATION REGISTER EXTERNAL DIODE OPEN-CIRCUIT INTERRUPT STATUS REGISTERS MASKING ADT7481 SMBUS INTERFACE 1 5 9 10 4 8 V GND SDATA SCLK THERM ALERT/THERM2 DD Figure 1. Functional Block Diagram Table 1. ABSOLUTE MAXIMUM RATINGS Parameter Rating Unit Positive Supply Voltage (V ) to GND 0.3 to +3.6 V DD D+ 0.3 to V + 0.3 V DD D to GND 0.3 to +0.6 V SCLK, SDATA, ALERT, THERM V 0.3 to +3.6 Input Current, SDATA, THERM 1 to +50 mA Input Current, D 1 mA ESD Rating, All Pins (Human Body Model) 1,500 V Maximum Junction Temperature (T ) 150 C J MAX Storage Temperature Range 65 to +150 C IR Reflow Peak Temperature 220 C IR Reflow Peak Temperature for Pb-Free 260 C Lead Temperature, Soldering (10 sec) 300 C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. NOTE: This device is ESD sensitive. Use standard ESD precautions when handling. Table 2. THERMAL CHARACTERISTICS Package Type Unit JA JC 10-lead MSOP 142 43.74 C/W