TC650/TC651

DS21450C-page 6

 2004 Microchip Technology Inc.

3.0

PIN DESCRIPTION

The descriptions of the pins are listed in Table 3-1.

TABLE 3-1:

PIN FUNCTION TABLE

3.1

Power Supply Input

May be independent of fan power supply.

3.2

Fan Shutdown, Active-low Input

During Shutdown mode, the chip still monitors

factory set point.

3.3

Ground

Ground return for all TC650/TC651 functions.

3.4

Overtemperature Alert

Active-low output.

3.5

PWM Fan Drive Output

Pulse width modulated rail-to-rail logic output. Nominal

frequency is 15 Hz.

Pin No.

Symbol

Description

Power Supply Input

2

NC

No Internal Connect

3

SHDN

Fan Shutdown, Active-low Input

1

= Fan in normal operation

0

= Fan in shutdown

4

GND

Ground

5

NC

No Connect

6

Overtemperature Alert, Active-low Output

1

= Overtemperature condition does not exist

0

= The device is in the overtemperature condition. The fan is driven at 100%.

Potential exists for system over-heating

7

GND

Ground

8

PWM

PWM Fan Drive Output