TD7623AFN_01 Datasheet, PDF (7/19 Pages) Toshiba Semiconductor – 3-WIRE AND I2C BUS SYSTEM, 2.3 GHz DIRECT TWO MODULUS-TYPE FREQUENCY SYNTHESIZER FOR CATV

TD7623AFN
OPERATION INSTRUCTIONS
The TD7623AFN can be controlled with either the 3-wire bus or standard I²C bus.
The 3-wire bus mode, the device is controlled by 27-bit serial data.
The I²C bus conforms to the standard I²C bus format. The bus supports two-way bus communications control,
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.
(This function is only valid when the I²C bus is selected. When the 3-wire bus is selected, the A / D converter
input pin function as the LOCK output pin.)
Addresses can be set using the hardware bits. Three programmable addresses are supported. 3-wire bus and
standard I²C bus are switches by the voltage applied on the BUS-SW pin.
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
BUS-SW
CL / SCL
DA / SDA
EN / ADR
LOCK / ADC
3-WIRE BUS MODE
[V_CC]
CLOCK INPUT
DATA INPUT
ENABLE INPUT
LOCK
I²C BUS MODE
[GND]
SCL INPUT
SDA IN / OUTPUT
ADDRESS
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 = fr × N
fosc : Program frequency
fr : Phase comparator reference frequency (Step frequency)
N : Counter total ratio
2001-03-01 7/19