Datasheet Standard LCD Segment Driver BU9794AKV MAX 200 segments (SEG50COM4) Features Key Specifications Integrated RAM for display data (DDRAM) : Supply Voltage Range: +2.5V to +5.5V 50 4bit (Max 200 Segment) LCD drive power supply Range: +2.5V to +5.5V LCD drive output : Operating Temperature Range: -40C to +85C 4 Common output, 50 Segment output Max Segments: 200 Segments Integrated Buffer AMP for LCD driving Display Duty: 1/4 Integrated Oscillator circuit Bias: 1/2, 1/3 selectable No external components Interface: 3wire serial interface Low power consumption design Independent power supply for LCD driving Package W (Typ.) x D (Typ.) x H (Max.) Applications Telephone FAX Portable equipment (POS, ECR, PDA etc.) DSC DVC Car audio Home electrical appliance Meter equipment, etc. VQFP64 12.00mm x 12.00mm x 1.60mm Typical Application Circuit VDD VLCD VDD COM0 VLCD COM1 COM2 COM3 CSB SD Controller Segment SCL VDD LCD SEG0 SEG1 INHb OSCIN TEST1 TEST2 VSS SEG49 Internal oscillator circuit mode Figure 1. Typical application circuit Product structure Silicon monolithic integrated circuit This product is not designed for protection against radioactive rays. www.rohm.com TSZ02201-0A0A2D300010-1-2 2013 ROHM Co., Ltd. All rights reserved. 1/22 TSZ22111 14 001 10.Apr.2015 Rev.004 BU9794AKV MAX 200 Segments (SEG50COM4) Block Diagram / Pin Configuration / Pin Description COM0COM3 SEG0SEG49 VLCD LCD voltageg enerator egment common driver driver 49 32 SEG38 SEG21 SEG39 SEG20 SEG40 SEG19 LCD SEG41 SEG18 BIAS SEG42 SEG17 SELECTOR blink timing common SEG43 SEG16 DDRAM generator counter SEG44 SEG15 SEG45 SEG14 SEG46 SEG13 SEG47 SEG12 VSS SEG48 SEG11 SEG49 SEG10 INHb COM0 SEG9 Command Command COM1 SEG8 OSCIN register D ata Decoder COM2 SEG7 OSCILLATOR COM3 SEG6 Power On Reset 64 17 serial inter face VDD IF FILTER VSS TEST2 TEST1 CSB SD SCL Figure 2. Block Diagram Figure 3. Pin Configuration (TOP VIEW) Table 1 Pin Description Handling when Terminal Terminal I/O Function unused No. VDD Input terminal for turning off display INHb 8 I H : turn on display L : turn off display GND Test input (ROHM use only) TEST1 9 I Must be connected to VSS GND Test input (ROHM use only) TEST2 10 I Must be connected to VSS External clock input. GND OSCIN 4 I External clock and Internal clock can be selected by command. Must be connected to VSS when internal oscillation circuit is used. GND SD 7 I Serial data input GND SCL 6 I Serial data transfer clock GND CSB 5 I Chip select : L active - VSS 3 GND - VDD 2 Power supply - VLCD 1 Power supply for LCD driving OPEN SEG0 to 49 11 to 60 O SEGMENT output for LCD driving OPEN COM0 to 3 61 to 64 O COMMON output for LCD driving www.rohm.com TSZ02201-0A0A2D300010-1-2 2013 ROHM Co., Ltd. All rights reserved. 2/22 TSZ22111 15 001 10.Apr.2015 Rev.004 11 1166 48 VLCD SEG37 VDD SEG36 VSS SEG35 OSCIN SEG34 CSB SEG33 SCL SEG32 SD SEG31 INHb SEG30 TEST1 SEG29 TEST2 SEG28 SEG0 SEG27 SEG1 SEG26 SEG2 SEG25 SEG3 SEG24 SEG4 SEG23 SEG5 SEG22 33