TC620/TC621

DS21439C-page 2

© 2006 Microchip Technology Inc.

Functional Block Diagrams

3

HIGH SET

2

LOW SET

5

CONTROL*

6

HIGH LIMIT

VDD

7

LOW LIMIT

8

4

*Suffix code "C" denotes cooling option (High true CONTROL output).

Suffix code "H" denotes heating option (Low true CONTROL output).

Q

S

R

Q

+

+

–

–

TC620

HIGH SET

LOW SET

1

THERMISTOR

CONTROL*

HIGH LIMIT

LOW LIMIT

Temp. to

Voltage

Converter

VREF

GEN

VREF

GEN

VREF

3

2

5

6

VDD

7

8

4

Q

S

R

Q

+

+

–

–

TC621

Thermistor

Interface

Circuit

VREF

GEN

VREF

GEN

VREF