SC9302X Ver la hoja de datos (PDF) - Silan Microelectronics

Número de pieza

componentes Descripción

Fabricante

SC9302X

1-MEMORY/2-MEMORY TONE/PULSE DIALER

Silan Microelectronics 

Silan

Semiconductors

SC9302 Series

PIN DESCRIPTION

Internal

Pin Name I/O

Connection

Description

These pins construct a 4x4 keyboard matrix to perform the keyboard

input detecting and dialing specification setting functions, when on-hook

( HKS =high) all the pins are set to high. While off-hook the column

group ( C1 ~ C4 ) stays low and the row group ( R1 ~ R4 ) is set to high

C1 ~ C4

I/O

R1 ~ R4

CMOS

IN/OUT

for key input detecting.

An inexpensive single contact 4x4 keyboard can be an input device.

Pressing a key connects a single column to a single row, and actuates

the system oscillator to result in a dialing signal output. If more than two

keys are pressed at the same time, no response can be brought about.

The key-in debounce time is 20ms. Refer to the keyboard table for

keyboard arrangement and to the functional description for dialing

specification selection.

X1

I

The system oscillator consists of an inverter, a bias resistor and the

necessary load capacitor on chip. Connecting a standard 3.579545MHz

OSCILLATOR crystal or ceramic resonator to X1 and X2 terminals can implement the

X2

O

oscillator function. The oscillator is turned off in the stand-by mode, and

is actuated whenever a keyboard entry is detected.

XMUTE

HKS

The XMUTE is an NMOS open drain structure pulled to VSS during

dialing signal transmitting. Otherwise, it is an open circuit. The

O

NMOS OUT

XMUTE is used to mute the speech circuit when transmitting the dial

signal.

This pin is used to monitor the status of the hook-switch and its

combination with HFI/ HDI can control the PO pin output to make or

break the line.

I

CMOS IN HKS =VDD: On-hook state ( PO =low). Except HFI/ HDI (hand-free

/ hold-line control input), other functions are all disabled.

HKS =VSS: Off-hook state ( PO =high). The chip is in the stand-by

mode and ready to receive the key input.

(to be continued)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 2.0 2001-11-01

9

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