BU21023GUL_16 Datasheet, PDF (11/21 Pages) Rohm – Resistive Type Touch Screen Controller ICs

BU21023GUL BU21023MUV BU21024FV-M
Application Examples
【BU21023GUL BU21023MUV】
BU21023GUL/MUV support 2 HOST interfaces (4-wire SPI and 2-wire serial bus).
The figures shown below are application circuits when each interface is used.
(Although BU21023GUL is CSP package, it is shown in similar figure for comparison.)
*Please connect the terminal of ECL/EDA to GND when downloading the firmware from the HOST.
ECL and EDA pins pull up to VDD if an external EEPROM is used. (example : 10kΩ)
*Please insert TVS diode or Zener diode to each sensor line to enhance resistance to ESD.
*Please pull up the INT terminal to VDD or HOST IO voltage (max 4.5V).
*In the case of 4-wire SPI use, please pull down the SO terminal to GND.
If not in use, connect it to the GND.
Host
VDD
option(*3)
10kohm
panel
option(*2)
option(*1)
10ohm
YN
1nF
10ohm
XN
1nF
10ohm
YP
1nF
10ohm
XP
1nF
BU21023
option(*5)
SO
(10kohm)
IFSEL
T3
T2
T1
CLK_EXT
RSTB
VDD
(*1) For Noise protection RC-LPF.
(Please select constant and design for requirement and environment)
(*2) For ESD protection. (Zener diode/TVS diode)
(*3) EEPROM interface PIN. Please pull-up to VDD in use.
(*5) Please pull-down as prevention against the SO terminal output Hi-Z.
0.1uF
1uF 1uF
1uF
Example 1: BU21023GUL/MUV Application Circuit (4-wireSPI)
In the case of 2-wire serial interface use,
please pull up the INT, SCL_SCK, SDA_SI terminal to VDD or HOST IO voltage(max4.5V).
panel
option(*2)
Host
VDD
option(*4)
option(*3)
10kohm
10kohm
10kohm
option(*1)
10ohm
YN
1nF
10ohm
XN
1nF
10ohm
YP
1nF
10ohm
XP
BU21023
SO
IFSEL
T3
T2
T1
CLK_EXT
RSTB
1nF
VDD
(*1) For Noise protection RC-LPF.
(Please select constant and design for requirement and environment)
(*2) For ESD protection. (Zener diode/TVS diode)
(*3) EEPROM interface PIN. Please pull-up to VDD in use.
(*4) Please connect to VDD when use as slave address = "BAh".
0.1uF
1uF 1uF
1uF
Example 2: BU21023GUL/MUV Application Circuit (2-wire Serial bus)
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TSZ22111・15・001
11/17
TSZ02201-0L5L0F300840-1-2
7.June.2016 Rev.004