cat3626 Catalyst Semiconductor, cat3626 Datasheet - Page 11

• Manufacturer Part Number: cat3626
• Description: 6-channel Led Driver With I?c Interface
• Manufacturer: Catalyst Semiconductor

I
The LED driver is interfaced through a 2-wire serial
I
each of the six LED channels. The SDA and SCL lines
comply with the I
be terminated with pull-up resistors. When the bus is
not used, both lines are high. The device supports the
maximum bus speed of 400kbit/s. The serial bit
sequence is shown below for read and write operations
into the registers. Read and write instructions are
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
2
2
C-bus in order to control the state and the current in
C INTERFACE
Read operation:
Write operation:
S
S
Slave address
Slave address
2
C electrical specification and should
Register address:
Slave address:
W
W
R, W:
Data:
A*:
A
A
S:
A:
P:
Device register address 8 bits
Data to read or write 8 bits
Start condition
Read bit (1), Write bit (0)
Acknowledge sent by the slave LED driver (SDA high)
Not Acknowledge sent by the master microcontroller (SDA low)
Stop condition
Device address 7 bits (MSB first, slave address is 1100110).
Register address
Register address
Write Instruction Sequence
11
initiated
acknowledged by the slave LED driver. The I
address of the driver is internally fixed to the binary
value 1100110. The protocol requires that the start bit
and the device address are both repeated. For further
details on the I
Specification, document number 9398 393 40011, from
Philips Semiconductors.
A
A
S
Data
by
Slave address
2
C protocol, please refer to the I
the
A
P
master
R
controller/CPU
A
Doc. No. MD-5014 Rev. C
Data
CAT3626
2
C-Bus
A* P
and
2
C