STCF05 STMicroelectronics, STCF05 Datasheet - Page 17

• Manufacturer Part Number: STCF05
• Description: HIGH POWER WHITE LED DRIVER WITH I2C INTERFACE
• Manufacturer: STMicroelectronics

Specifications of STCF05

• Flash Mode: up to 400 mA
• Torch Mode: up to 120 mA

STCF05
Figure 7.
8.5
Table 8.
8.6
S
A
R
T
T
M
S
B
7
Device address + R/W bit
6
5
Acknowledge on I²C bus
Interface protocol
The interface protocol is composed of
- A start condition (START)
- A Device address + R/W bit (read =1 / write =0)
- A Register address byte
- A sequence of data n* (1 byte + acknowledge)
- A stop condition (STOP)
The register address byte determines the first register in which the read or write operation
takes place. When the read or write operation is finished, the register address is
automatically incremented.
Interface protocol
Writing to a single register
Writing to a single register starts with a START bit followed by the 7 bit device address of
STCF05. The 8
operation. Then the master waits for an acknowledge from STCF05. Then the 8 bit address
of register is sent to STCF05. It is also followed by an acknowledge pulse. The last
transmitted byte is the data that is going to be written to the register. It is again followed by
an acknowledge pulse from STCF05. The master then generates a STOP bit and the
communication is over. See
4
3
2
S
B
1
L
th
W
R
0
bit is the R/W bit, which is 0 in this case. R/W = 1 means a reading
C
A
K
M
S
B
7
6
Figure 8
Register address
Doc ID 15257 Rev 4
5
4
below.
(Figure
3
2
1
5):
S
B
0
L
C
A
K
M
S
B
7
6
5
4
Data
3
I²C bus interface
2
1
S
B
0
L
C
A
K
17/33
O
S
T
P