PCF8579HT/1: NXP's Low-Power 96-Segment LCD Driver for Advanced Display Applications
The demand for efficient and highly integrated display solutions continues to grow across consumer, industrial, and automotive applications. Addressing this need, the PCF8579HT/1 from NXP Semiconductors stands out as a specialized peripheral driver designed to simplify the control of complex liquid crystal displays (LCDs). This CMOS device provides a complete, low-power solution for driving up to 96 segments, making it an ideal choice for advanced display panels that require numerous indicators, symbols, and alphanumeric characters.
A key strength of the PCF8579HT/1 is its high level of integration, which significantly reduces the component count and design complexity for system engineers. It incorporates both the segment and backplane drivers, an LCD bias voltage generator, and a powerful I²C-bus interface all on a single chip. This architecture allows a microcontroller (MCU) with a standard two-wire I²C interface to control the entire display with minimal GPIO pin consumption. The built-in voltage generator can create the necessary LCD bias voltages (up to 3x the input supply) from a single low-voltage power supply, eliminating the need for an external booster circuit and further simplifying the board design.
Engineers will particularly appreciate the device's extremely low power consumption, a critical parameter for battery-operated and portable devices. The PCF8579HT/1 is optimized for minimal quiescent current draw. Furthermore, it includes a powerful software-configured blinking mode that can be activated without any ongoing intervention from the host MCU. This allows the central processor to enter a deep sleep or low-power mode while the display continues to show dynamic, blinking information, leading to substantial overall energy savings for the end product.
The versatile I²C-bus interface is another cornerstone of its design. It supports standard, fast, and high-speed modes (up to 400 kbit/s), ensuring fast data transfer for updating complex displays. The interface also allows for multiple devices to be connected on the same bus, enabling the driving of very large displays through a daisy-chain configuration. This scalability is essential for applications requiring more than 96 segments. The onboard 96-bit display data RAM (DD RAM) stores the current state of each segment, which is automatically compared to new data; only changed segments are updated. This intelligent feature minimizes communication overhead on the I²C bus and reduces power consumption.
In summary, the PCF8579HT/1 delivers a robust, flexible, and power-efficient solution for modern LCD-based user interfaces. Its combination of high segment count, integrated voltage generation, and an intelligent serial interface makes it a superior choice for designers aiming to enhance functionality without compromising on power budget or board space.
ICGOODFIND: The PCF8579HT/1 is a highly integrated and power-optimized LCD driver from NXP, offering a complete solution for controlling complex 96-segment displays via a simple I²C interface. Its built-in features drastically reduce external component count and MCU overhead, making it an excellent choice for portable, battery-powered devices across various industries.
Keywords: Low-Power Consumption, I²C-Bus Interface, 96-Segment LCD Driver, Integrated Voltage Generator, Display Data RAM.
