AXT Systems

PFC-1 PWM Fan Control Module
PFC-1 Module
The PFC-1 module is a temperature based PWM fan control module. It will control 4 PWM fans based on the average temperatures read from a string of 1 or more TSM-1 temperature sensor modules.

The module has front panel LEDs to show the current temperature reading in 10 degree C increments from 30C to 60C. 

It is based on the ADT7470 PWM temperature sense and control device, which handles the periodic temperature sensor reading and the PWM control of the fans.
A PIC16LF15324 device acts to initialise the temperature sensing device and get readings from it to update the front panel LED indicators.

The module measures 50mm x 50mm and has been used with power amplifier equipment to provide an indication of the heatsink operating temperature and, if required, to control fans for cooling.

It is powered with a 12V DC input, which is used to power the 12VDC fans, and also is regulated down to 3.3VDC for the digital circuitry.