Touch Panel Interface - Quectel SC690A Series Hardware Design

You can design external backlight drive circuit for LCM according to actual requirement. The reference
designs are shown in the figures below, in which PWM is used for backlight brightness adjustment.
PWM
GND
Module
Figure 18: LCM External Backlight Driver Reference Circuit
NOTE
LCM is powered by LCD_VDD_2V8, which is an external LDO power supply.

4.10. Touch Panel Interface

The module provides one I2C interface for connection with touch panel (TP), and provides the
corresponding power supply and interrupt pins. The pin definition of touch panel interfaces is illustrated
below.
Table 22: Pin Definition of Touch Panel Interfaces
Pin Name
TP_RST
TP_INT
TP_I2C_SCL
TP_I2C_SDA
SC690A_Series_Hardware_Design
VPH_PWR
C1
Pin No. I/O
138 DO
139 DI
140 OD
206 OD
Backlight
Driver
Description
TP reset
TP interrupt
TP I2C clock
TP I2C data
Smart Module Series
LCD_BL_A
LCD_BL_K1
LCD_BL_K2
Comment
1.8 V power domain.
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