TC9400/9401/9402
2.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1:
PIN FUNCTION TABLE
Symbol
I
BIAS
ZERO ADJ
I
IN
V
SS
V
REF
OUT
GND
V
REF
PULSE FREQ
OUT
OUTPUT
COMMON
FREQ/2 OUT
THRESHOLD
DETECTOR
NC
V
DD
Description
This pin sets bias current in the TC9400. Connect to V
SS
through a 100kΩ resistor.
Low frequency adjustment input.
Input current connection for the V/F converter.
Negative power supply voltage connection, typically -5V.
Reference capacitor connection.
Analog ground.
Voltage reference input, typically -5V.
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.
Source connection for the open drain output FETs.
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.
Input to the Threshold Detector. This pin is the frequency input during F/V operation.
Pin No.
14-Pin PDIP/CERDIP
14-Pin SOIC (Narrow)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
AMPLIFIER OUT Output of the integrator amplifier.
No internal connection.
Positive power supply connection, typically +5V.
©
DS21483B-page 6
2002 Microchip Technology Inc.