U9131X

Preliminary

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

2 of 11

www.unisonic.com.tw

QW-R502-A34.a

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PIN CONFIGURATION

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PIN DESCRIPTION

PIN NO.

PIN NAME

DESCRIPTION

1-4 &

15-18

Column-Row

Inputs

The keyboard input may be from either the standard 4×4 keyboard or an inexpensive

single contact (from A) keyboard. Electronic input from a μC can also be used. A valid

key entry is defined as a single row being connected to a single column.

5

B/M

The break make ratio is 60:40 if B/M=1 and is 66.6:33.3 if B/M=0. This pin has no

function in DTMF mode.

7, 8

XT, XT

A built-in inverter provides oscillation with an inexpensive 3.579545MHz crystal or

ceramic resonator.

9

T/P MUTE

The T/P MUTE is a conventional CMOS N-channel open drain output. The output

transistor is switched on during pulse and tone mode dialing sequence and flash break.

Otherwise, it is switched off.

13

MODE

the dialer in pulse mode (10ppS). Leaving mode pin floating places the dialer in pulse

mode (20ppS).

10

HKS

Hook switch input. HKS=1: On-book state. Chip in sleeping mode, no operation. HKS=0:

internal resistor.

11

DP

N-channel open drain dialing pulse output (Figure 1). Flash key will cause DP to go

active in both pulse mode and tone mode.

12

DTMF

In pulse mode, remains in low state at all times. In tone mode, outputs a dual or single

tone. Detailed timing diagram for tone mode is shown in Figure 2 (a, b).

OUTPUT FREQUENCY

Specified

Actual

Error %

R1

697

699

+0.28

R2

770

766

-0.52

R3

852

848

-0.47

R4

941

948

+0.74

C1

1209

1216

+0.57

C2

1336

1332

-0.30

C3

1477

1472

-0.34

14, 6

Power input pins.