點晶科技股份有限公司

SILICON TOUCH TECHNOLOGY INC.

ST1111N

SP-ST1111N-A.004(2007-07-12)

Version

：

A.004

Page

：5

Application Notes

There is no requirement of protection diode for power reverse fault in normal

applications. The reverse protection function is built-in.

The FG pin is an open-drained output dividing the frequency sensed by HALL IC

with 2. With suitable output pull up, the fan tachometer output can be used

directly with bipolar or MOS logic for motor speed monitoring/control.

There is no requirement of the bypass capacitor or Zener Diode between VDD

and GND in normal applications. The connection of this capacitor or Zener Diode

between VDD and GND will increase stability of operation, if required.

The power dissipated by the IC varies widely with the supply voltage, the output

current, and loading.

It is important to ensure the application does not exceed

the allowable power dissipation of the IC package.

The recommended motor

driver power dissipation versus temperature is depicted as follows:

Power Dissipation-Temperature

0

50

100

150

200

250

300

350

400

0

25

50

75

100

125

150

Ambient Temperature ( ℃ )