NXP PCF2119x LCD驱动方案

NXP公司的PCF2119x 是LCD控制器/驱动器,可以驱动2x16或1x32字符的5x8点阵LCD.单芯片中集成了包括LCD偏压产生在内的所有功能,和大多数MCU的接口为4位或8位总线或2线I2C总线,主要应用在通信设备,手提设备和POS终端.本文介绍了PCF2119x主要特性,方框图,采用并行接口4位或8位总线的应用电路, 采用I2C接口的应用电路,以及2x16和1x32字符LCD连接图.

PCF2119x LCD controllers/drivers

The PCF2119x is a low power CMOS1 LCD controller and driver, designed to drive a dot matrix LCD display of 2-lines by 16 characters or 1-line by 32 characters with 5 x8 dot format. All necessary functions for the display are provided in a single chip, including on-chip generation of LCD bias voltages, resulting in a minimum of external components and lower system current consumption. The PCF2119x interfaces to most microcontrollers via a 4-bit or 8-bit bus or via the 2-wire I2C-bus. The chip contains a character generator and displays alphanumeric and kana (Japanese) characters.

The letter ‘x’ in PCF2119x characterizes the built-in character set. Various character sets can be manufactured on request. In addition 16 user defined symbols (5x8 dot format)
are available.

PCF2119x主要特性:

Single-chip LCD controller and driver

2-line display of up to 16 characters plus 160 icons or 1-line display of up to 32 characters plus 160 icons

5x7 character format plus cursor; 5 x8 for kana (Japanese) and user defined symbols

Reduced current consumption while displaying icons only

Icon blink function

On-chip:

Configurable 4, 3 or 2 times voltage multiplier generating LCD supply voltage,
independent of VDD, programmable by instruction (external supply also possible)

Temperature compensation of on-chip generated VLCDOUT:- 0.16 %/K to-0.24 %/K (programmable by instruction)

Generation of intermediate LCD bias voltages

Oscillator requires no external components (external clock also possible)

Display Data RAM (DDRAM): 80 characters

Character Generator ROM (CGROM): 240 characters (5 x8)

Character Generator RAM (CGRAM): 16 characters (5 x8); 4 characters used to drive 160 icons, 8 characters used if icon blink feature is used in application

4-bit or 8-bit parallel bus and 2-wire I2C-bus interface

CMOS compatible

18 row and 80 column outputs

Multiplex rates 1:18 (2-line display or 1-line display), 1:9 (for 1-line display of up to 16 characters and 80 icons) and 1:2 (for icon only mode

Uses common 11 code instruction set (extended)

Logic supply voltage: VDD1 VSS1 = 1.5 V to 5.5 V (chip may be driven with two battery cells)

LCD supply voltage: VLCDOUT VSS2 = 2.2 V to 6.5 V

VLCD generator supply voltage: VDD2 VSS2 = 2.2 V to 4 V and VDD3 VSS2 = 2.2 V to 4 V

Direct mode to save current consumption for icon mode and multiplex drive mode 1:9 (depending on VDD2 value and LCD liquid properties)

Very low current consumption (20uA to 200uA):

Icon mode: < 25 uA

Power-down mode: < 2 uA

Icon mode is used to save current. When only icons are displayed, a much lower LCD operating voltage can be used and the switching frequency of the LCD outputs is reduced; in most applications it is possible to use VDD as LCD supply voltage

PCF2119x 应用:

Telecom equipment

Portable instruments

Point-of-sale terminals

图1.PCF2119x方框图

图2.PCF2119x采用并行接口,4位或8位总线的应用电路

图3.PCF2119x采用I2C接口的应用电路

图4.PCF2119x和2x16字符LCD连接图

图5.PCF2119x和1x32字符LCD连接图