ADT7476AARQZ-R ON Semiconductor

ADT7476A Remote Thermal Controller and Voltage Monitor The ADT7476A controller is a thermal monitor and multiple PWM fan controller for noise-sensitive or power-sensitive applications requiring active system cooling. The ADT7476A can drive a fan using www.onsemi.com either a low or high frequency drive signal and can monitor the temperature of up to two remote sensor diodes plus its own internal temperature. The part also measures and controls the speed of up to four fans, so the fans operate at the lowest possible speed for minimum acoustic noise. The automatic fan speed control loop optimizes fan speed for a given temperature. The effectiveness of the systems thermal QSOP24 NB solution can be monitored using the THERM input. The ADT7476A CASE 492B also provides critical thermal protection to the system using the bidirectional THERM pin as an output to prevent system or PIN ASSIGNMENT component overheating. 1 24 SDA PWM1/XTO Features SCL 2 23 V CCP Monitors Up to Five Voltages GND 3 22 +2.5V /THERM IN Improved TACH and PWM Performance V 4 21 +12V /VID5 CC IN Controls and Monitors Up to Four Fans VID0/GPIO0 5 20 +5V IN High and Low Frequency Fan Drive Signal VID1/GPIO1 6 19 VID4/GPIO4 ADT7476A One On-Chip and Two Remote Temperature Sensors VID2/GPIO2 7 18 D1+ (Top View) Extended Temperature Measurement Range Up to 191C VID3/GPIO3 8 17 D1 Automatic Fan Speed Control Mode Controls System Cooling Based TACH3 9 16 D2+ PWM2/ on Measured Temperature 10 15 D2 SMBALERT Enhanced Acoustic Mode Dramatically Reduces User Perception of 11 14 TACH1 * Changing Fan Speeds TACH2 12 13 PWM3/ADDREN Thermal Protection Feature via THERM Output Monitors Performance Impact of Intel Pentium 4 Processor *TACH4/THERM/SMBALERT/GPIO6/ADDR SELECT Thermal Control Circuit via THERM Input 3-wire and 4-wire Fan Speed Measurement MARKING DIAGRAMS Limit Comparison of All Monitored Values 5.0 V Support on all TACH and PWM Channels Meets SMBus 2.0 Electrical Specifications ADT7476AARQZ YYWW This Device is Pb-Free, Halogen Free and is RoHS Compliant xxxx ADT7476AARQZ = Specific Device Code = Pb-Free Package YYWW = Date Code xxxx = Assembly Lot Code ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 68 of this data sheet. Semiconductor Components Industries, LLC, 2016 1 Publication Order Number: February, 2016 Rev. 7 ADT7476A/DADT7476A ADDR ADDREN SELECT SCL SDA SMBALERT ADT7476A VID5/GPIO5 VID4/GPIO4 SMBus VID3/GPIO3 SERIAL BUS ADDRESS VID/GPIO VID2/GPIO2 INTERFACE SELECTION REGISTER VID1/GPIO1 VID0/GPIO0 ADDRESS GPIO6 POINTER REGISTER PWM1 PWM REGISTERS AUTOMATIC PWM2 AND CONTROLLERS FAN SPEED PWM (HF AND LF) CONTROL PWM3 CONFIGURATION REGISTERS TACH1 TACH2 FAN SPEED INTERRUPT COUNTER TACH3 MASKING TACH4 PERFORMANCE MONITORING THERMAL THERM INTERRUPT PROTECTION STATUS V TO ADT7476A CC REGISTERS ACOUSTIC V CC ENHANCEMENT D1+ CONTROL LIMIT D1 COMPARATORS INPUT D2+ SIGNAL 10-BIT D2 CONDITIONING ADC +5V VALUE AND IN AND LIMIT +12V IN ANALOG REGISTERS MULTIPLEXER +2.5V IN BAND GAP V CCP REFERENCE BAND GAP TEMP. SENSOR GND Figure 1. Functional Block Diagram t F t LOW t HD STA t R SCL t t HD STA HIGH t t SU STA SU STO t t HD DAT SU DAT SDA t BUF S PS P Figure 2. Serial Bus Timing Diagram www.onsemi.com 2