F75387A is a system hardware monitoring and automatic fan speed controlling IC specific designed for graphic cards and PC etc. The F75387A can monitor several critical hardware parameters of the system, including voltages, temperatures and fan speeds which are very important for the system to work stably and properly.
An 11-bit analog-to-digital converter (ADC) was built inside F75387A. The chip can monitor up to 4 analog voltage inputs, 2 fan tachometer inputs and 3 temperature inputs (2 remote and 1 local sensor). The remote temperature sensor can be performed by thermistor, transistor 2N3906 and CPU/GPU thermal diode. The F75387A can provide automatic fan speed control so that the system can operate at the minimum acoustic noise. This chip supports not only PWM duty mode (PWM) but also linear mode (DAC 0 ~ 3.3V) for fan speed control. The F75387A supports two fan control mechanisms: manual mode and auto mode where auto mode provides stage & linear mode. Internal oscillator was built in this chip and user can use the external clock input if users need the accurate fan speed count. Also the users can set up the upper and lower limits (alarm thresholds) of all monitored parameters and the F75387A can also issue warning messages for the system protection when there is something wrong with monitored items.
Through the BIOS or application software, the users can read all the monitored parameters of the system all the time. A pop-up warning can be also activated when the monitored item was out of the proper or pre-setting range. The F75387A is in the package of 16-pin SOP and powered by 3.3V.
4 voltage inputs
Provide 2 remote and 1 on-chip local temperature sensor
Temperature measure range: 0°C to 145°C and -60°C ~127°C.
Up to 2 fan speed monitoring inputs and 2 automatic fan speed control
Support multi temperature fan control method
2-wire SMBus interface
Power on fan speed configuration
- 100% or 60% PWM duty cycle output on initial
- 3.3V or 1.98V DAC linear voltage output on initial
Provide up to 4 system protection signals
- OVT#, SMI#, FAN_FAULT#, VOLT_FAULT# signals
Programmable limited and setting points(alert threshold) for all monitored items
VCC3V operation and 16-SOP package(150mil)