MAX8738 Datasheet, PDF (12/13 Pages) Maxim Integrated Products – EEPROM-Programmable TFT VCOM Calibrator with I2C Interface

EEPROM-Programmable TFT VCOM
Calibrator with I²C Interface
Table 1. Command Byte Functions
BYTE
00h
FFh
AAh
55h
11h
FUNCTION
Decrement the DAC setting by 1 LSB
Increment the DAC setting by 1 LSB
Write the current DAC setting to EEPROM
Load the EEPROM setting to the DAC
Write a specific value to the DAC
FIGURE
8A
8A
8A
8A
8B
Command Byte
A complete command consists of a START condition
(S) followed by the MAX8738’s slave address (5Eh) and
a command byte, or a command byte and a DAC
value, followed by a STOP condition (P). There are five
commands, and their functions are listed in Table 1.
DAC Values
Table 2 lists the DAC values and the corresponding
I_SET, V_SET, and V_OUT values.
Layout Information
Use the following guidelines for good layout:
1) Place the VCOM buffer and the R1/R2 voltage-
divider close to the OUT pin (Figure 2).
2) Place R_SET close to SET.
Table 2. DAC Settings
DAC VALUE
FFh
FEh
.
.
.
01h
00h
I_SET
I_SET(MAX)
I_SET(MAX) -
1 LSB
.
.
.
I_SET(MIN) +
1 LSB
I_SET(MIN)
V_SET (V)
V_SET(MAX)
V_SET(MAX) -
1 LSB
.
.
.
V_SET(MIN) +
1 LSB
V_SET(MIN)
V_OUT (V)
V_MIN
V_MIN +
1 LSB
.
.
.
V_MAX -
1 LSB
V_MAX
3) Bypass V_DD and AVDD with 0.1µF capacitors
placed close to the IC with short connections to the
pins.
4) Refer to the MAX8738 evaluation kit for an example
of proper board layout.
Chip Information
TRANSISTOR COUNT: 6198
PROCESS: BiCMOS
START
S
SLAVE ADDRESS
ACK
(A) FOR THE 00H, FFH, AAH, AND 55H COMMANDS
START
S
SLAVE ADDRESS
ACK
(B) FOR THE DAC INITIAL VALUE-SETTING COMMAND
Figure 8. I²C Bus Data Transfer Summary
COMMAND BYTE
SET DAC VALUE (11H)
STOP
P
ACK
DAC VALUE
ACK
STOP
P
ACK
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