3-281

TELCOM SEMICONDUCTOR, INC.

7

6

5

4

3

1

2

8

TC7652

LOW NOISE, CHOPPER-STABILIZED OPERATIONAL AMPLIFIER

FUNCTIONAL BLOCK DIAGRAM

1

2

3

4

8

7

6

5

C

A

OUTPUT

TC7652CPA

–INPUT

+INPUT

C

B

CLAMP

1

2

3

4

5

6

7

14

13

12

11

10

9

8

NC

NC = NO INTERNAL CONNECTION

(MAY BE USED AS INPUT GUARD)

INT/EXT

EXT CLK

IN

INT CLK

OUT

OUTPUT

OUTPUT

CLAMP

RET

C

–INPUT

+INPUT

NC

TC7652CPD

C

B

C

A

TC7652

NULL

NULL

OUTPUT

B

B

A

C

EXT

C

EXT

NULL

AMPLIFIER

MAIN

AMPLIFIER

OUTPUT CLAMP

CIRCUIT

INTERMOD

COMPARATOR

OSCILLATOR

B

A

INT/EXT

EXT CLK IN

CLK OUT

14-PIN DIP ONLY

BA

INPUTS

OUTPUT CLAMP

(NOT ON "Z" PINOUT)

TC7652-7 9/11/96

FEATURES

s

Low Offset Over Temperature Range ............ 10

s

Ultra-Low Long-Term Drift ................. 150nV/Month

s

Low Temperature Drift ............................. 100nV/

s

Low DC Input Bias Current ............................. 15pA

s

High Gain, CMRR and PSRR ................. 110dB Min

s

Low Input Noise Voltage ......... 0.2

s

Internally-Compensated for Unity-Gain Operation

s

Clamp Circuit for Fast Overload Recovery

GENERAL DESCRIPTION

The TC7652 is a lower noise version of the TC7650,

sacrificing some input specifications (bias current and band-

width) to achieve a 10x reduction in noise. All the other

benefits of the chopper technique are present, i.e. freedom

from offset adjust, drift, and reliability problems from exter-

nal trim components. Like the TC7650, the TC7652 re-

quires only two noncritical external caps for storing the

chopped null potentials. There are no significant chopping

spikes, internal effects or overrange lockup problems.

PIN CONFIGURATIONS

ORDERING INFORMATION

Temperature

Part No.

Package

Range

TC7652CPA

8-Pin Plastic DIP

0

°C to +70°C

TC7652CPD

14-Pin Plastic DIP

0

°C to +70°C