Touch Panel Interface - Quectel SC20 Series Hardware Design

3.19. Touch Panel Interface

SC20 series provides an I2C interface for connection with Touch Panel (TP), and it also provides the
corresponding power supply and interrupt pins. The pin definition of TP interface is illustrated below.
Table 23: Pin Definition of Touch Panel Interface
Pin Name Pin No.
LDO6_1V8 125
LDO17_2V85 129
TP_INT 30
TP_RST 31
TP_I2C_SCL 47
TP_I2C_SDA 48
The following illustrates a TP interface reference circuit, by taking the connection with TP interface of
LHR050H41-00 (IC: GT9147) from HUARUI Lighting as an example.
TP_I2C_SDA
TP_I2C_SCL
TP_RST
TP_INT
Module
SC20_Series_Hardware_Design
I/O Description
1.8 V output power supply for
PO TP I/O power domain and I2C
pull-up circuit
2.85 V output power supply
PO
for TP VDD
DI TP interrupt
DO TP reset
OD TP I2C clock
OD TP I2C data
LDO6_1V8
R1 R2
2.2K 2.2K
D1 D2
Figure 23: Reference Circuit Design for TP Interface
LDO17_2V85
D4
D3
C1 C2
4.7 μF 100 nF
Smart Module Series
Comment
Vnom = 1.8 V
I max = 100 mA
O
Vnom = 2.85 V
I max = 300 mA
O
1.8 V power domain.
1.8 V power domain.
Active low.
1.8 V power domain.
1.8 V power domain.
1
SDA 1.8 V
2
SCL 1.8 V
3
RESET 1.8 V
4
INT 1.8 V
5
GND
6
VDD 2.8 V
D5
TP
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