Rev0.7 May. 29, 2009(LF)

Technology

FS211F

FG Output: The Circuit Diagram of Open Collector Transistor

Figure 7 the small signal transistor output connected with the pull-up resistance is to limit the

current and confirm the voltage level of rotation speed. The situation of the long-time operation

with the high voltage or with the high current will do damage to the transistor and cause FG

malfunction.

Figure 8 illustrates the relation between dynamic magnetic field and FG.

1

R

FG output

VC

Pull-up resistance

Fig.7 FG Circuit Diagram

N pole

S pole

VFG

0

0V

(Depend on supply voltage)

Fig.8 FG Waveform