Datasheet

1. General description
The PCF85176 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 40 segments. It can be easily
cascaded for larger LCD applications. The PCF85176 is compatible with most
microcontrollers and communicates via the two-line bidirectional I
2
C-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).
For a selection of NXP LCD segment drivers, see Table 24 on page 49
.
2. Features and benefits
 Single chip LCD controller and driver
 Selectable backplane drive configuration: static, 2, 3, or 4 backplane multiplexing
 Selectable display bias configuration: static,
1
⁄
2
, or
1
⁄
3
 Internal LCD bias generation with voltage-follower buffers
 40 segment drives:
 Up to 20 7-segment numeric characters
 Up to 10 14-segment alphanumeric characters
 Any graphics of up to 160 segments/elements
 40  4-bit RAM for display data storage
 Auto-incremented display data loading across device subaddress boundaries
 Display memory bank switching in static and duplex drive modes
 Versatile blinking modes
 Independent supplies possible for LCD and logic voltages
 Wide power supply range: from 1.8 V to 5.5 V
 Wide logic LCD supply range:
 From 2.5 V for low-threshold LCDs
 Up to 6.5 V for guest-host LCDs and high-threshold twisted nematic LCDs
 Low power consumption
 400 kHz I
2
C-bus interface
 May be cascaded for large LCD applications (up to 2560 segments/elements possible)
 No external components required
 Manufactured in silicon gate CMOS process
PCF85176
40 x 4 universal LCD driver for low multiplex rates
Rev. 5 — 6 January 2015 Product data sheet
1. The definition of the abbreviations and acronyms used in this data sheet can be found in Section 21.