Microchip MCP4017数字电位器应用方案

Microchip 公司的MCP4017/18/19是通用的数字电位器,具有7位电阻网络分辨率,有127个电阻,具有低的温度系数:绝对值(0-70度C)为50ppm,比值为10ppm,工作电压1.8V到5.5V. MCP4017/18/19可应用在设定电或失调调整,传感器校准,替代机械式电位计和可选择增益和失调放大器设计.本文介绍了MCP4017/18/19的主要特性, 方框图, 和微控制器(MCU) 典型连接框图, 采用MCP4017调整非反相放大器失调和增益方框图以及采用MCP4018的可编滤波器和采用MCP4017的惠斯通电桥调整框图.

The MCP4017/18/19 devices are general purpose digital potentiometers intended to be used in applications where a programmable resistance with moderate bandwidth is desired.

This Data Sheet covers a family of three Digital Potentiometer and Rheostat devices. The MCP4018 device is the Potentiometer configuration, while the MCP4017 and MCP4019 devices are the Rheostat configuration.

MCP4017/18/19主要特性:

Potentiometer or Rheostat configuration options

7-bit: Resistor Network Resolution

127 Resistors (128 Steps)

Zero Scale to Full Scale Wiper operation

RAB Resistances: 5 kΩ, 10 kΩ, 50 kΩ, or 100 kΩ

Low Wiper Resistance: 100Ω (typical)

Low Tempco:

Absolute (Rheostat): 50 ppm typical (0℃ to 70℃)

Ratiometric (Potentiometer): 10 ppm typical

Simple I2C Protocol with read & write commands

Brown-out reset protection (1.5V typical)

Power-on Default Wiper Setting (Mid-scale)

Low-Power Operation:

2.5 μA Static Current (typical)

Wide Operating Voltage Range:

2.7V to 5.5V - Device Characteristics Specified

1.8V to 5.5V - Device Operation

MCP4017/18/19应用:

Applications generally suited for the MCP401X devices include:

Set point or offset trimming

Sensor calibration

Selectable gain and offset amplifier designs

Cost-sensitive mechanical trim pot replacement



图1.MCP4017/18/19方框图



图2.MCP4017/18/19和微控制器(MCU)典型连接框图



图3.MCP4017/18/19设定电或阈值校准



图4.采用MCP4017调整非反相放大器失调和增益方框图



图5.采用MCP4018的可编滤波器



图6.采用MCP4017的惠斯通电桥调整框图