NXP Semiconductors PCF8576T/1,118

Overview

PCF8576T/1,118 from NXP Semiconductors (formerly Philips) is a single-chip I²C-bus LCD controller/driver supporting static or 2/3/4-backplane multiplexing, 40 segment outputs (S0–S39), and internal LCD bias generation with selectable 1/2 or 1/3 bias. It operates from 2 V to 9 V logic/LCD supplies and delivers up to 160-element graphics drive capability in applications such as portable instrumentation displays.

For engineers reviewing the PCF8576T/1,118 datasheet, PCF8576T/1,118 pinout, PCF8576T/1,118 application, or PCF8576T/1,118 equivalent, this page provides verified technical context, exact pin functions for the VSO56 package, confirmed display RAM organization (40 × 4-bit), real-world blinking and cascading behavior, and validated alternatives for low-multiplex LCD systems requiring I²C interface and battery-efficient operation.

Technical Context

The PCF8576T/1,118 implements a fully integrated LCD drive architecture with hardware-controlled subaddressing, auto-incremented data pointer, and synchronized output bank selection across static, 1:2, 1:3, and 1:4 multiplex modes. Its internal oscillator supports frequency tuning via external resistor Rosc (f_CLK ≈ 3.4×10⁷/R_OSC kHz), while external clock mode accepts f_CLK ≥ 125 kHz for full 100 kHz I²C-bus compliance.

Display RAM mapping is strictly mode-dependent: static mode uses bit-0 only per address; 1:2 uses bits 0–1; 1:3 uses bits 0–2; 1:4 uses all 4 bits - with direct one-to-one correspondence between RAM columns and backplane outputs (BP0–BP3). Cascaded operation relies on SYNC signal synchronization and hardware subaddress inputs (A0–A2, SA0) to enable seamless multi-device addressing without software overhead.

Key Specifications

Pinout & Package

PCF8576T/1,118 is housed in a 56-lead plastic Very Small Outline package (VSO56, SOT190-1), optimized for plane wiring in single- and multi-device LCD modules. Pin pitch is 0.5 mm; body dimensions are 13.6 mm × 5.6 mm × 1.6 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with PCF8576T/1,118, PCF8566T/1,112 offers identical interface and cascade behavior but reduced segment capacity, making it suitable for cost-sensitive compact displays; PCF8574AT/1,118 is fundamentally incompatible as an LCD driver due to absence of bias generation, multiplex timing, and dedicated segment outputs.

Availability

PCF8576T/1,118 is available at Aetrix Electronics and suitable for portable medical instruments, industrial panel meters, home appliance control panels, and telecom handset displays requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for PCF8576T/1,118 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, formerly Philips Semiconductors, is a global leader in high-performance mixed-signal ICs, with expertise in interface, power management, and human-machine interaction solutions.

The PCF8576T/1,118 belongs to NXP's legacy LCD peripheral family, designed specifically for low-multiplex-rate character and segment-based displays in battery-constrained and industrial environments where reliability, I²C simplicity, and minimal external components are critical.

FAQ

What is the maximum number of LCD segments the PCF8576T/1,118 can drive?

The PCF8576T/1,118 supports up to 40 segment outputs (S0–S39) and 4 backplane outputs (BP0–BP3), enabling drive of up to 160 display elements (4 × 40) in 1:4 multiplex mode. In static mode, it drives 40 segments with one backplane. The actual segment count depends on the selected multiplex configuration - 40 in static, 80 in 1:2, 120 in 1:3, or 160 in 1:4 - as defined by the MODE SET command and RAM bit allocation.

Does the PCF8576T/1,118 require external resistors for LCD bias generation?

No, the PCF8576T/1,118 includes an internal three-resistor LCD bias divider between VDD and VLCD, with programmable center-resistor bypass for 1/2-bias selection in 1:2 mode. Only one external resistor (R_OSC) is required if using the internal oscillator; no resistors are needed for bias generation itself. VLCD is externally supplied and may be temperature-compensated for stable contrast.

Can multiple PCF8576T/1,118 devices be cascaded, and how is synchronization handled?

Yes, PCF8576T/1,118 supports cascading via the SYNC pin (pin 3), which propagates frame-aligned timing signals between devices. Each unit is assigned a unique I²C slave address using SA0 and A0–A2 inputs. Subaddressing ensures automatic wrap-around to the next device when display RAM boundaries are exceeded, enabling seamless expansion to up to 2560 segments (64 × 40) without software address management.

What are the valid supply voltage ranges for VDD and VLCD on the PCF8576T/1,118?

VDD operates from 2.0 V to 9.0 V, powering the logic core and I²C interface. VLCD is independently supplied from 0 V to VDD − 1.5 V (min), with typical values set to achieve V_op = VDD − VLCD between 2.5 V and 7.0 V depending on LCD threshold voltage. This dual-supply flexibility allows use with low-threshold (2 V) portable LCDs and high-threshold (up to 9 V) automotive twisted-nematic displays.

How does the PCF8576T/1,118 handle blinking functionality, and is it hardware- or software-controlled?

The PCF8576T/1,118 provides hardware-based blinking: full-display blink frequencies (0.5/1/2 Hz) are set via the BLINK command and derived from the internal clock; segment-selective blink in static and 1:2 modes uses output bank switching - no MCU involvement required. In 1:3/1:4 modes, blinking is implemented by toggling RAM data at fixed intervals via I²C writes, retaining hardware efficiency for common use cases.