Datasheet ADT7470 (Analog Devices) - 5

Data Sheet ADT7470 ABSOLUTE MAXIMUM RATINGS Table 3.
Stresses above those listed under Absolute Maximum Ratings
Parameter Rating
may cause permanent damage to the device. This is a stress Positive Supply Voltage (VCC) 6.5 V rating only; functional operation of the device at these or any Voltage on Any TACH or PWM Pin –0.3 V to +6.5 V other conditions above those indicated in the operational Voltage on Any Input or Output Pin –0.3 V to VCC + 0.3 V section of this specification is not implied. Exposure to absolute Maximum Junction Temperature (TJ max) 150°C maximum rating conditions for extended periods may affect Storage Temperature Range –65°C to +150°C device reliability. Lead Temperature, Soldering
ESD CAUTION
Vapor Phase, 60 sec 215°C Infrared, 15 sec 200°C ESD Rating (HBM) 3000 V
THERMAL CHARACTERISTICS
16-Lead QSOP Package: θJA = 105°C/W θJC = 39°C/W Rev. E | Page 5 of 40 Document Outline Features Applications General Description Functional Block Diagram Revision History Specifications Serial Bus Timing Specifications Absolute Maximum Ratings Thermal Characteristics ESD Caution Pin Configuration and Function Descriptions Functional Description General Description ADT7470 Monitoring Cycle Configuration Register 1 (Address 0x40) Configuration Register 2 (Address 0x74) ID Registers General-Purpose I/O Pins (Open Drain) SMBus/I2C Serial Interface Address Selection Serial Bus Protocol Write Operations Send Byte Write Byte Read Operations Receive Byte Alert Response Address SMBus Timeout Temperature Measurement Using TMP05/TMP06 Measuring Temperature TMP05/TMP06 Decoder Temperature ReadBack By the Host Temperature Data Format Temperature Measurement Limits Thermal Zones for Automatic Fan Control Thermal Zone TMIN Limit and Status Registers Limit Values Temperature Limits Fan Speed Limits Out-of-Limit Comparisons Status Registers SMBALERT Interrupt Handling SMBALERT Interrupts Masking Interrupt Sources Enabling the SMBALERT Interrupt Output Fan Drive Using PWM Control High Frequency Fan Drive Low Frequency Fan Drive Setting the Fan Drive Frequency Inverted PWM Output Fan Full Speed Function Fan Speed Measurement Tach Inputs Pulse Stretching Disabling Tach measurement Fan Speed Measurement Fan Speed Measurement Registers Reading Fan Speed from the ADT7470 Fan Tach Limit Registers Fan Speed Measurement Rate Calculating Fan Speed and Tachometer Limits Fan Pulses per Revolution Manual Fan Speed Control Setting the PWM Duty Cycle Example 1: For a PWM Duty Cycle of 50% Example 2: For a PWM Duty Cycle of 33% Automatic Fan Speed Control PWM Min Duty Cycle Example: For a PWM Min Duty Cycle of 30% PWN Max Duty Cycle PWM Current Duty Cycle Register Map Detailed Register Descriptions Outline Dimensions Ordering Guide