F75387
1. General Description
F75387 is a system hardware monitoring and automatic fan speed controlling IC specific designed
for graphic cards and PC etc. The F75387 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 F75387. 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 F75387 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
(PWMOUT) but also linear mode (DACOUT 0 ~ 3.3V) for fan speed control. Internal oscillator was
built in this chip and user can use external clock input if users need accurate fan speed count. Also
the users can set up the upper and lower limits (alarm thresholds) of all monitored parameters and
the F75387 can also issue warning messages for 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
system all the time. And a pop-up warning can be also activated when the monitored item was out of the
proper/pre-setting range. The F75387 is in the package of 16-pin SOP/SSOP and powered by 3.3V
2. Features
4 voltage inputs
Provide 2 remote and 1 on-chip local temperature sensor
Up to 2 fan speed monitoring inputs and 2 automatic fan speed control
Power on fan speed configuration
z
100% or 60% PWM duty cycle output on initial
3.3V or 1.98V DAC linear voltage output on initial
z
Provide up to 4 system protection signals
OVT#, SMI#, FAN_FAULT#, VOLT_FAULT# signals
z
Programmable limited and setting points(alert threshold) for all monitored items
2-wire SMBus interface
VCC3V operation and 16-SOP/SSOP package(150mil)
Noted: Patented TW207103 TW207104 TW220442 US6788131 B1 TW235231 TWI263788
4
July, 2007
0.27P