SI570 Datasheet, PDF (13/26 Pages) Silicon Laboratories – ANY-RATE I2C PROGRAMMABLE XO/VCXO

3.3. I²C Interface
The control interface to the Si570 is an I²C-compatible
2-wire bus for bidirectional communication. The bus
consists of a bidirectional serial data line (SDA) and a
serial clock input (SCL). Both lines must be connected
to the positive supply via an external pullup. Fast mode
operation is supported for transfer rates up to 400 kbps
as specified in the I²C-Bus Specification standard.
Figure 3 shows the command format for both read and
write access. Data is always sent MSB first. The timing
specifications and timing diagram for the I²C bus can be
found in the I²C-Bus Specification standard (fast mode
operation). The device I²C address is specified in the
part number.
S Slave Address 0 A Byte Address A
Data
A
Write Command
Data
AP
S Slave Address 0 A Byte Address A S Slave Address 1 A Data A Data A P
Read Command
Address auto incremented after each data read or write
From master to slave
From slave to master
A – Acknowledge (SDA LOW)
S – START condition
P – STOP condition
Figure 3. I²C Command Format
Si570/Si571
Rev. 0.3
13