SBAS475A
June 2009 – January 2023
AMC6821-Q1
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Description (continued)
6
Pin Configuration and Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Timing Requirements
7.7
Typical Characteristics
8
Detailed Description
8.1
Functional Block Diagram
8.2
Feature Description
8.2.1
ADC Converter
8.2.2
Temperature Sensor
8.2.2.1
Series Resistance Cancellation
8.2.2.2
Reading Temperature Data
8.2.2.3
Temperature Out-of-Range Detection
8.2.2.4
Remote Temperature Sensor Failure Detection
8.2.3
PWM Output
8.2.4
PWM Waveform Setting
8.2.5
Fan Speed Measurement
8.2.5.1
Tach-Data Register
8.2.5.1.1
Reading the Tach Data Register
8.2.5.1.2
RPM Measurement Rate
8.2.5.1.3
Select Number of Pulses/Revolution
8.2.5.1.4
Tach Mode Selection
8.2.5.1.5
Fan RPM Out-of-Range Detection
8.2.6
Fan Failure Detection
8.2.7
FAN-FAULT Pin
8.2.8
Fan Control
8.2.8.1
THERM Pin and External Hardware Control
8.2.8.1.1
THERM Pin as an Output
8.2.8.1.2
THERM Pin as an Input
8.2.8.2
Fan Spin-Up
8.2.8.3
Normal Fan Speed Control
8.2.8.3.1
Software DCY Control Mode
8.2.8.3.2
Software-RPM Control Mode (Fan Speed Regulator)
8.2.8.3.3
Auto Temperature Fan Mode
8.2.9
Interrupt
8.2.9.1
OVR Pin
8.2.9.2
SMBALERT Pin
8.2.9.3
SMBALERT Interrupt Behavior
8.2.9.4
Handling SMBALERT Interrupts
8.3
Device Functional Modes
8.4
Programming
8.4.1
SMBus Interface
8.4.1.1
Communication Protocols
8.4.2
SMBus Alert Response Address (ARA)
8.4.3
Power-On Reset and Start Operation
8.5
Register Map
8.5.1
Register Description
8.5.1.1
Device Configuration Registers
8.5.1.2
Device Status Registers
8.5.1.3
Fan Controller Registers
8.5.1.4
Temperature Data Registers
8.5.1.5
Temperature Limit Registers
8.5.1.5.1
Tach-Data Register
8.5.1.5.2
Tach Setting Register
8.5.1.5.3
Tach Low Limit Register
8.5.1.5.4
Tach High Limit Register
9
Application and Implementation
9.1
Power Supply Recommendations
10
Device and Documentation Support
10.1
Receiving Notification of Documentation Updates
10.2
Support Resources
10.3
Trademarks
10.4
Electrostatic Discharge Caution
10.5
Glossary
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
DBQ|16
MSOI004H
Thermal pad, mechanical data (Package|Pins)
Orderable Information
sbas475a_oa
sbas475a_pm
1
Features
Qualified for automotive applications:
Junction temperature: –40°C to +150°C, T
J
Functional Safety-Capable
Documentation available to aid functional safety system design
Remote temperature sensor:
±3°C accuracy, 0.250°C resolution
Local temperature sensor:
±3°C accuracy, 0.250°C resolution
PWM controller
PWM frequency: 10 Hz to 40 kHz
Duty cycle: 0% to 100%, 8 bits
Automatic fan speed control loops
SMBus interface
Power: 2.7 V to 5.5 V
Package (green): SSOP-16 (4mm × 5mm)
RoHS-compliant
Latch-up exceeds 100 mA
per JESD78B - class I