General description
The PCF85132 is a peripheral device which interfaces to almost any Liquid Crystal Display (LCD)1
with low multiplex rates. It generates the drive signals for any static or multiplexed LCD containing up to four backplanes and up to 160 segments. It can be easily cascaded for larger LCD applications. The PCF85132is compatible with most microprocessors or microcontrollers and communicates via a two-line bidirectional I2C-bus. Communication overheads are minimized by a display RAM with auto-incremented addressing, by hardware subaddressing, and by display memory switching (static and duplex drive modes).

Features and benefits
„ Single-chip LCD controller and driver for up to 640 elements
„ Selectable backplane drive configuration: static, 2, 3, or 4 backplane multiplexing
„ 160 segment drives:
    ‹Up to eighty 7-segment numeric characters
    ‹Up to forty 14-segment alphanumeric characters
    ‹Any graphics of up to 640 elements
„ May be cascaded for large LCD applications (up to 5120 elements possible)
„ 160×4-bit RAM for display data storage
„ Software programmable frame frequency in steps of 5 Hz in the range of 60 Hz to 90 Hz; factory calibrated
„ Wide LCD supply range: from 1.8 V for low threshold LCDs and up to 8.0 V for guest-host LCDs and high threshold (automobile) twisted nematic LCDs „
Internal LCD bias generationwith voltage-follower buffers
„ Selectable display bias configuration: static, 1⁄2, or 1⁄3
„ Wide power supply range: from 1.8 V to 5.5 V
„ LCD and logic supplies may be separated
„ Low power consumption, typical: IDD= 4 μA, IDD(LCD)= 30 μA
„ 400 kHz I2C-bus interface
„ Auto-incremental display data loading across device subaddress boundaries
„ Versatile blinking modes
„ Compatible with Chip-On-Glass (COG) technology
„ No external components
„ Two sets of backplane outputs for optimal COG configurations of the application