TC642B View Datasheet(PDF) - Microchip Technology

Part Name

Description

Manufacturer

TC642B

PWM Fan Speed Controllers With Minimum Fan Speed, Fan Restart and FanSense™ Technology for Fault Detection

Microchip Technology 

TC642B/TC647B

Power-Up

Normal

Operation

Power-on

Reset

FAULT = 1

Yes

VMIN < VSHDN?

No

Fire Start-up

Timer

(1 sec)

Shutdown

VOUT = 0

No

VMIN > VREL?

Yes

Fan Pulse

Detected?

Yes

Normal

Operation

Fire Start-up

No

Timer

(1 sec)

Yes Fan Pulse

Detected?

No

Fan Fault

Clear Missing

Pulse Detector

Yes

VMIN < VSHDN?

No

VIN > VOTF? Yes

FAULT = 0

Shutdown

VOUT = 0

No

VMIN > VREL?

Yes

Power-Up

No

VOUT

Proportional to Greater

of VIN or VMIN

TC642B Only

Yes Fan Pulse No

Detected?

M.P.D.

No Expired?

Yes

Fire

Diagnostic

Timer

(100 msec)

Fan Fault

FAULT = Low,

VOUT = High

Yes

VMIN<VSHDN?

Shutdown

VOUT = 0

No

No

16 Pulses

Detected?

No

Yes

VMIN > VREL?

Power-Up

Yes

Normal

Operation

FIGURE 4-9:

TC642B/TC647B Behavioral Algorithm.

Yes

Fan Pulse

Detected?

No Fire Start-up

Timer

(1 sec)

Yes

Fan Pulse

Detected?

No

Fan Fault

DS21756C-page 16

 2002-2013 Microchip Technology Inc.

Share Link: