NXP Semiconductors PCF8576T,112

Overview

PCF8576T,112 from NXP Semiconductors (formerly Philips) is a single-chip I²C-compatible LCD controller/driver supporting static or 2/3/4-backplane multiplexing, 40 segment outputs (S0–S39), internal LCD bias generation, and 40 × 4-bit display RAM. It operates from 2 V to 9 V logic/LCD supplies and enables low-power display control in battery-powered instrumentation and consumer interfaces.

For engineers reviewing the PCF8576T,112 datasheet, PCF8576T,112 pinout, PCF8576T,112 application, or PCF8576T,112 equivalent, key selection criteria include its VSO56 package compatibility, I²C-bus timing at up to 100 kHz, selectable 1/2 or 1/3 LCD bias, cascading support for up to 2560 segments, and power-saving mode reducing frame rate by 6× for ultra-low quiescent current.

Technical Context

The PCF8576T,112 integrates an I²C-bus controller with command decoder, display RAM auto-increment addressing, hardware subaddressing (A0–A2, SA0), and synchronized output bank switching for static and duplex drive modes. Its oscillator supports internal RC timing (via OSC–VSS + Rosc) or external clock input (OSC–VDD), with CLK output enabling cascade synchronization of PCF8566 devices.

Display data routing uses a shift register to feed the display latch, which drives 40 segment outputs in phase with four backplane outputs (BP0–BP3). The LCD voltage selector dynamically configures bias waveforms per MODE SET commands, delivering Von(rms)/Voff(rms) ratios of 0.577/0.333 (1:4, 1/3 bias) or 0.791/0.354 (1:2, 1/2 bias) based on Vop = VDD − VLCD.

Key Specifications

Pinout & Package

PCF8576T,112 is housed in a space-saving 56-lead plastic Very Small Outline package (VSO56; SOT190-1), optimized for plane wiring in single- and multi-device LCD systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LCD controller/driver applications.

Compared with PCF8576T,112, PCF8566T,112 offers reduced segment density but identical cascade interoperability, while HD44102L trades I²C simplicity for higher MCU resource usage and no built-in low-power display modes.

Availability

PCF8576T,112 is available at Aetrix Electronics and suitable for industrial panel meters, consumer remote controls, automotive instrument clusters, and medical patient monitors requiring stable component supply across long-lifecycle production programs.

Supply support for PCF8576T,112 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with roots in Philips' pioneering analog and mixed-signal IC development.

The PCF8576T,112 belongs to NXP's universal LCD driver product line, designed specifically for cost-sensitive, low-multiplex-rate character and graphic displays in battery-powered and automotive-grade instrumentation.

FAQ

What is the maximum number of LCD segments supported by the PCF8576T,112 in a single-device configuration?

The PCF8576T,112 supports up to 160 LCD elements in a single-device configuration - achieved with 4 backplanes and 40 segments (4 × 40). This enables twenty 8-segment numeric characters, ten 15-segment alphanumeric characters, or any custom 160-dot graphic layout. Cascading multiple PCF8576T,112 devices extends total segment count to 2560.

How does the PCF8576T,112 generate LCD bias voltages without external components?

The PCF8576T,112 uses an internal three-resistor divider between VDD and VLCD to generate fractional bias levels (1/2 or 1/3). The center resistor is switchable to select 1/2 bias for 1:2 multiplex mode. Vop is defined as VDD − VLCD, and VLCD can be externally temperature-compensated to maintain contrast stability - eliminating need for external bias networks.

Can the PCF8576T,112 operate with separate logic and LCD supply voltages?

Yes, the PCF8576T,112 supports independent logic (VDD) and LCD (VLCD) supplies. VDD powers internal logic and I²C interface (2 V to 9 V), while VLCD sets LCD bias level (also 2 V to 9 V). This separation prevents digital switching noise from coupling into analog LCD drive signals and enables optimization of each supply for contrast and power efficiency.

What I²C slave address options are available for the PCF8576T,112?

The PCF8576T,112 supports two I²C slave addresses: 0x70 and 0x71, selected by the SA0 pin (low = 0x70, high = 0x71). Combined with hardware subaddress inputs A0–A2, it allows up to eight distinct memory-mapped subregions within one device, simplifying multi-byte display RAM access without repeated address bytes.

Does the PCF8576T,112 support blinking for partial display areas, not just the full screen?

Yes, the PCF8576T,112 supports selective blinking in static and 1:2 multiplex modes using display RAM bank switching. By loading alternate data into bits 2 (static) or bits 2–3 (1:2) and toggling the BANK SELECT command, arbitrary segments can blink independently - without CPU intervention or I²C traffic during blink cycles.