SF32LB52-DevKit-LCD Adapter Board Fabrication Guide

This document describes how to make a companion adapter board for the SF32LB52-DevKit-LCD development board, for debugging third-party displays, WiFi modules, and other devices.

QSPI-LCD Interface Adapter Board

The QSPI-LCD adapter board can be adapted from the 22-pin FPC connector or from the 40-pin dual-row header.

22-pin FPC Adaptation Method

../_images/52Kit-22p-FPC-pin-define.png
SF32LB52-DevKit-LCD 22-pin assignment

Pin

Pin Name

Function

1

LEDK

LCD backlight diode cathode

2

LEDA

LCD backlight diode anode

3

PA_07

MIPI-DBI(8080) B0, QSPI D2, LCD interface signal

4

PA_08

MIPI-DBI(8080) B1, QSPI D3, LCD interface signal

5

PA_37

MIPI-DBI(8080) B2, LCD interface signal

6

PB_39

MIPI-DBI(8080) B3, LCD interface signal

7

PB_40

MIPI-DBI(8080) B4, LCD interface signal

8

PA_41

MIPI-DBI(8080) B5, LCD interface signal

9

PA_42

MIPI-DBI(8080) B6, LCD interface signal

10

PA_43

MIPI-DBI(8080) B7, LCD interface signal

11

PA_02

MIPI-DBI(8080) TE, QSPI TE, LCD interface signal

12

PA_00

LCD Reset, LCD interface signal

13

PA_04

MIPI-DBI(8080) WRx, QSPI CLK, SPI CLK, LCD interface signal

14

PB_05

MIPI-DBI(8080) RDx, QSPI D0, SPI SDI, LCD interface signal

15

PA_03

MIPI-DBI(8080) CSx, QSPI CS, SPI CS, LCD interface signal

16

PA_06

MIPI-DBI(8080) DCx, QSPI D1, SPI DC, LCD interface signal

17

VDD_3V3

3.3V power output

18

PA_31

Touchscreen INT interrupt signal

19

PA_33

Touchscreen I2C_SDA signal

20

PA_30

Touchscreen I2C_SCL signal

21

PA_09

Touchscreen RTN reset signal

22

GND

Ground

The 22-pin FPC connector on the SF32LB52-DevKit-LCD development board supports MIPI-DBI (8080) and SPI (3-/4-wire, 2-/4-data) interfaces. The data format can be adapted by configuring the I/O MUX in software.

../_images/52Kit-LED-driver.png

The SF32LB52-DevKit-LCD development board provides one LED driver with a default drive current of 40 mA. The LED drive current can be adjusted by changing the resistance of R0110 according to the LED circuit structure and current requirements of the LCD display.

Important

  1. The adapter board is connected to the SF32LB52-DevKit-LCD development board through an FPC cable. During design, pay attention to the FPC pin sequence on the adapter board; it must be crossed over relative to the signal definitions on the development board.

  2. The VDD_3V3 power supply in the FPC connector interface can power the display driver and touchscreen driver on the adapter board.

  3. The I/O level of the development board is 3.3 V. If the I/O level of the driver chip on the LCD adapter board is 1.8 V, use a level shifter for level conversion.

  4. If the adapter board requires a 5 V power supply, use the 40-pin dual-row header as the adapter interface.

  5. Series resistors have already been added to the display interface on the development board, so no additional series resistors are required on the adapter board.

40-pin Dual-Row Header Adapter Method

../_images/52Kit-2x20p-pin-define.png
SF32LB56-DevKit-LCD 40-pin signal definition

Pin

Pin Name

Function

1

3V3

3v3 power

2

5V

5v power

3

IO2

PA_42 or PA_14

4

5V

5v power

5

IO3

PA_41 or PA_12

6

GND

Ground

7

IO4

PA_43 or PA_13

8

IO14

PA_27

9

GND

Ground

10

IO15

PA_20

11

IO17

PA_08, MIPI-DBI(8080) B1, QSPI D3, LCD interface signal

12

IO18

PA_05, MIPI-DBI(8080) RDx, QSPI D0, SPI SDI, LCD interface signal

13

IO27

PA_40 or PA_17                      

14

GND

Ground

15

IO22

PA_39 or PA_16

16

IO23

PA_37 or PA_15

17

3V3

3v3 power

18

IO24

PA_38

19

IO10

PA_24

20

GND

Ground

21

IO9

PA_25

22

IO25

PA_07, MIPI-DBI(8080) B0, QSPI D2, LCD interface signal

23

IO11

PA_28

24

IO8

PA_29

25

GND

Ground

26

IO7

PA_31, Touchscreen INT interrupt signal

27

IO0

PA_30, Touchscreen I2C_SCL signal

28

IO1

PA_22

29

IO5

PA_23

30

GND

Ground

31

IO6

PA_33, Touchscreen I2C_SDA signal

32

IO12

PA_00, LCD Reset, LCD interface signal

33

IO13

PA_01, BL PWM, LCD interface signal

34

GND

Ground

35

IO19

PA06, MIPI-DBI(8080) DCx, QSPI D1, SPI DC, LCD interface signal

36

IO16

PA02, MIPI-DBI(8080) TE, QSPI TE, LCD interface signal

37

IO26

PA09, Touchscreen RTN reset signal

38

IO20

PA04, MIPI-DBI(8080) WRx, QSPI CLK, SPI CLK, LCD interface signal

39

GND

Ground

40

IO21

PA03, MIPI-DBI(8080) CSx, QSPI CS, SPI CS, LCD interface signal

Important

  1. The adapter board is connected to the SF32LB52-DevKit-LCD development board through a 40p dual-row header, and the adapter board is mounted on top of the development board.

  2. The 3V3 and 5V power supplies in the 40p dual-row header interface can power the display driver and touchscreen driver on the adapter board.

  3. The I/O level of the development board is 3.3 V. If the I/O level of the driver chip on the LCD adapter board is 1.8 V, use a level shifter for level conversion.

  4. The display backlight circuit needs to be integrated on the adapter board.

  5. Series resistors have already been added to the display interface on the development board, so no additional series resistors are required on the adapter board.

MIPI-DBI (8080) Interface Adapter Board

Refer to the QSPI-LCD Interface Adapter Board section.

EDP E-Paper Display Interface Adapter Board

WiFi Module Adapter Board