PMBus 5-Channel Power-Supply Manager and Intelligent Fan Controller

The MAX34441 is a complex system monitor that can manage up to five power supplies and a fan. The power-supply manager monitors the power-supply output voltage and constantly checks for user-programmable overvoltage and undervoltage thresholds. It can also margin the power-supply output voltage up or down to a user-programmable level. The margining is performed in a closed-loop arrangement whereby the device automatically adjusts a pulse-width-modulated (PWM) output and then measures the resultant output voltage. The power-supply manager can also sequence the supplies in any order at both power-up and power-down. With the addition of an external current-sense amplifier, the device can also monitor currents.

The device also contains closed-loop fan-speed control. Based on user-programmable settings for fan-control PWM duty cycles or RPM speeds at particular temperature breakpoints, the device automatically adjusts the fan speed in a manner to reduce audible noise and power consumption.

Applications

* Base Stations * Industrial Controls * Network Switches/Routers * Servers * Smart Grid Network Systems

* 5 Channels of Power-Supply Management

* Voltage Measurement/Monitoring

* Differential 12-Bit 1% Accurate ADC

* Min/Max Threshold Excursion Detection

* Supports Current Monitoring with External Current-Sense Amplifier

* Automatic Closed-Loop Margining

* Programmable Up and Down Sequencing

* Power-Good Output

* 1 Channel of Fan Control

* Supports 3-Wire and 4-Wire Fans

* Automatic Closed-Loop Fan-Speed Control

* Support for Dual Tachometer Fans

* Fan-Fault Detection

* Supports Up to Six Temperature Sensors

* External Thermal Diode Interface with Automatic Series Resistance Cancellation

* One Internal Temperature Sensor

* Support for Up to Four Additional I²C Digital Temp Sensor ICs

* Fault Detection on All Temp Sensors

* PMBus™-Compliant Command Interface

* I²C/SMBus™-Compatible Serial Bus with Bus Timeout Function

* On-Board Nonvolatile Fault Logging and Default Configuration Setting

* No External Clocking Required

* +3.3V Supply Voltage