Only For Training And Service Purposes - LG -S310 Service Manual

The figure 1 shows the timing diagram of I2C interface. The RT9367C communicates with a host (master)
using the standard I2C 2-wire interface. The two bus lines of SCL and SDA must be pulled to high when the
bus is not in use. External pull-up resistors between VCC and SDA/SCL pin are necessary. The recommended
pull-up resistor value range is from 2kΩ to 10kΩ. After the START condition, the I2C master sends a chip
address. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The
RT9367C address is 1010100 (54h) and is a receive-only (slave) device. The second word selects the register to
which the data will be written. The third word contains data to write to the selected register.
[Figure 3.11-2] RT9367C I2C Writing Cycles for LDO and LED Driver
Figure 3.11-2 shows the writing information of dual LDO and LED current. In the second word, the sub-
address of dual LDO is "001" and the sub-address of LED Driver is "010". For LDO, the LDO1 address is defined
as "000", LDO2 address is defined as "001". The data of second byte (B0 to B3), a "0" indicates a DISABLE and a
"1" indicates an ENABLE function. The data of third byte (C0 to C4) indicates a 32-steps setting of LDO1, LDO2
output voltage or the LED current of backlight.
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Only for training and service purposes

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3. TECHNICAL BRIEF
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