3-23

TELCOM SEMICONDUCTOR, INC.

7

6

5

4

3

1

2

8

PIN DESCRIPTION

Pin No

Pin No

Pin No

(TC500, 500A) (TC510)

(TC514)

Symbol

Description

122

Integrator output. Integrator capacitor connection.

2

Not Used

Not Used

Negative power supply input (TC500/500A only).

333

Auto-zero input. The Auto-zero capacitor connection.

4

4

4

BUF

Buffer output. The Integrator capacitor connection.

5

5

5

ACOM

This pin is grounded in most applications. It is recommended that

ACOM and the input common pin (V

–

–

analog common mode range (CMR).

666

REF

Input. Negative reference capacitor connection.

777

C

+

REF

Input. Positive reference capacitor connection.

888

V

–

REF

Input. External voltage reference (–) connection.

999

V

+

REF

Input. External voltage reference (+) connection.

10

15

Not Used

V

–

IN

Negative analog input.

11

16

Not Used

V

+

IN

Positive analog input.

12

18

22

A

Input. Converter phase control MSB. (See input B.)

13

17

21

B

Input. Converter phase control LSB. The states of A, B place the

TC5xx in one of four required phases. A conversion is complete

when all four phases have been executed:

00: Integrator Zero

Phase control input pins: AB =

01: Auto Zero

10: Integrate

11: Deintegrate

14

19

23

CMPTR OUT

Zero crossing comparator output. CMPTR is HIGH during the

Integration phase when a positive input voltage is being integrated

and is LOW when a negative input voltage is being integrated. A

HIGH-to-LOW transition on CMPTR signals the processor that the

Deintegrate phase is completed. CMPTR is undefined during the

Auto-Zero phase. It should be monitored to time the Integrator Zero

phase (see text).

15

23

27

DGND

Input. Digital ground.

16

21

25

Input. Power supply positive connection.

22

26

CAP

+

Input. Negative power supply converter capacitor (+) connection.

24

28

CAP–

Input. Negative power supply converter capacitor (–) connection.

11

V

–

OUT

Output. Negative power supply converter output and reservoir

capacitor connection. This output can be used to power other

devices in the circuit requiring a negative bias voltage.

20

24

OSC

Oscillator control input. The negative power supply converter normally

runs at a frequency of 100kHz. The converter oscillator frequency can

be slowed down (to reduce quiescent current) by connecting an

istics Curves).

18

Positive analog input pin. MUX channel 1.

13

CH1

–

Negative analog input pin. MUX channel 1.

17

Positive analog input pin. MUX channel 2.

12

Negative analog input pin. MUX channel 2.

16

Positive analog input pin. MUX channel 3.

11

CH3

–

Negative analog input pin. MUX channel 3.

15

Positive analog input pin. MUX channel 4.

PRECISION ANALOG FRONT ENDS

TC500

TC500A

TC510

TC514