TC9400/9401/9402

DS21483B-page 6

© 2002 Microchip Technology Inc.

2.0

PIN DESCRIPTIONS

The descriptions of the pins are listed in Table 2-1.

TABLE 2-1:

PIN FUNCTION TABLE

Pin No.

14-Pin PDIP/CERDIP

14-Pin SOIC (Narrow)

Symbol

Description

2

ZERO ADJ

Low frequency adjustment input.

Input current connection for the V/F converter.

Negative power supply voltage connection, typically -5V.

Reference capacitor connection.

6

GND

Analog ground.

Voltage reference input, typically -5V.

8

PULSE FREQ

OUT

Frequency output. This open drain output will pulse LOW each time the Freq.

Threshold Detector limit is reached. The pulse rate is proportional to input voltage.

9OUTPUT

COMMON

Source connection for the open drain output FETs.

10

FREQ/2 OUT

This open drain output is a square wave at one-half the frequency of the pulse output

(Pin 8). Output transitions of this pin occur on the rising edge of Pin 8.

11

THRESHOLD

DETECTOR

Input to the Threshold Detector. This pin is the frequency input during F/V operation.

12

AMPLIFIER OUT

Output of the integrator amplifier.

13

NC

No internal connection.

14

Positive power supply connection, typically +5V.