Datasheet 4-wire resistive Touch Screen Controller BU21021GUL General Description Key Specification BU21021GUL is a resistive touch screen controller, Power supply voltage 2.7V to 3.6V which is capable of detecting 2 points touch with a Temperature range -20 to 85 legacy 4-wire resistive touch screen. BU21021GUL is Standby current 5.0uA (Max.) capable of detecting X/Y coordinates, touch pressure in Sleep current 60uA (Typ.) 1 point detection mode, and a pair of X/Y coordinates in Operating current 4.0mA (Typ.) 2 point detection mode. Coordinate resolution It is also capable of recognizing multiple finger gestures 12bit from coordinate data variation and notifying to host with gesture detection flags respectively. Package BU21021GUL employs embedded CPU for noise VCSP50L2 2.70 mm x 2.65 mm x 0.55(max) mm filtering, coordinate calculation, gesture detection and other signal processing required on a chip. Application Equipments with user Interface employing 4-wire Feature resistive touch screen. Legacy 4-wire resistive touch screen is applicable Mobile phone, Tablet PC, PDA or other portable 1 point / 2 points touch detection information devices. On chip coordinate generation Digital still camera, Digital video camera, portable TV Multiple gesture detections or other Audio-visual devices. 3V single power supply Note PC, Touch screen monitor, printer or other PC Higher coordinate resolution with 12-bit SAR A/D peripherals. converter On chip clock generator Selectable HOST I/F(IFSEL pin) 4-wire SPI / 2-wire serial bus Application Circuit Example (2-wire serial I/F, Slave address=B8h, non-use EEPROM) Figure 1. Application circuit example Product structureSilicon monolithic integrated circuit This product is not designed protection against radioactive rays . www.rohm.com TSZ02201-0L5L0F300970-1-2 2012 ROHM Co., Ltd. All rights reserved. 1/11 TSZ2211114001 30.Nov.2016 Rev.002DatasheetDatasheet BU21021GUL Pin Layout 1 2 3 4 5 A T4 PVDD DVDD VDD DVSS B XP AVDD AVSS DVDD EXT C XN YP RSTB T1 T2 D YN SEL CSB SO T3 IFSEL E ECL EDA SCL SCK SDA SI INT Top view Figure 2. Pin Layout Pin Descriptions Equivalent Pin no. Pin Name I/O Description circuit D1 YN I/O YN channel input. D C1 XN I/O XN channel input. D C2 YP I/O YP channel input. D B1 XP I/O XP channel input. D A1 T4 I/O Test input / output. D A2 PVDD O Regulator output for touch screen voltage supply. D B3 AVDD O Regulator output for analog circuit. D A3 DVDD I/O Regulator output for digital circuit D B4 AVSS - Analog ground. - A4 VDD - Chip power supply. - A5 DVSS - Digital ground. - B5 DVDD EXT I Digital power supply select. L=internalH=external A C3 RSTB I Reset (Low active) C C4 T1 I Test input. A C5 T2 I Test input. A D4 T3 I Test input. A D5 IFSEL I Host interface select. (L=4-wire SPI, H=2-wire serial) A D3 SO O 2-wire serial High impedance 4-wire SPI Data output E E5 INT O Interrupt E D2 SEL CSB I 2-wire serial Slave address select 4-wire SPI Chip select C E4 SDA SI I/O 2-wire serial Data input / output 4-wire SPI Data input B E3 SCL SCK I 2-wire serial Clock input 4-wire SPI Clock input B E2 EDA I/O SDA for EEPROM B E1 ECL I/O SCL for EEPROM B (*1) Bypass AVDD and DVDD to GND with 1.0 uF capacitor and PVDD and T4 need terminal opening. (*2) Digital voltage can be supplied by DVDD when DVDD EXT=H. (*3) ECL and EDA need pull-up with 4.7k resister in use case. If not use, connect to GND. (*4) SCL SCK and SDA SI need pull-up with over 4.7k resister and SO need terminal opening when use 2-wire serial I/F. (*5) Above parameters are only recommended for use. Absolute reliability is not guaranteed. (*6) When VDD is not supplied, state of RSTB=H is prohibition. www.rohm.com TSZ02201-0L5L0F300970-1-2 2012 ROHM Co., Ltd. All rights reserved. 2/11 TSZ2211115001 30.Nov.2016 Rev.002