TD7623AFN

2001-03-01 7/19

OPERATION INSTRUCTIONS

The 3-wire bus mode, the device is controlled by 27-bit serial data.

consisting of WRITE mode where data are received and READ mode where data are transmitted. In READ

mode, the voltage applied on the A / D converter input pin can be transmitted and output with 5-level

resolution.

Addresses can be set using the hardware bits. Three programmable addresses are supported. 3-wire bus and

The power-on reset circuit is built in this product, and the detection voltage is designed about 1.4 V.

If it raises to voltage of operation after making it stop for a while near the voltage of a power-on reset circuit of

operation at the time of starting of a power supply, a power-on reset circuit may not operate normally.

FUNCTION CHART

NAME

3-WIRE BUS MODE

I

2

C BUS MODE

BUS-SW

[GND]

CL / SCL

CLOCK INPUT

SCL INPUT

DA / SDA

DATA INPUT

SDA IN / OUTPUT

EN / ADR

ENABLE INPUT

ADDRESS

LOCK

/ ADC

LOCK

ADC

― 3-WIRE BUS COMMUNICATIONS CONTROL ―

The 3-wire bus mode, the device is controlled by 27-bit serial data.

The 3-wire bus sets the following data : (bandswitch information and programmable counter information,

charge-pump current setting, reference frequency divider ratio setting, and testing item functions.)

The program frequency can be calculated in the following formula :

fosc :

Program frequency

:

Phase comparator reference frequency (Step frequency)

N

:

Counter total ratio