26 lines
765 B
Markdown
26 lines
765 B
Markdown
|
---
|
|||
|
|
title: 电流监测设计
|
|||
|
|
updated: 2022-01-11 09:17:39Z
|
|||
|
|
created: 2022-01-11 09:00:03Z
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
# 选型
|
|||
|
|
电流检测的核心是差分放大，集成IC用起来比较方便 [INA219](../../AMO_Driver/ADC/型号/INA219.md) 和 [MCP3421](../../AMO_Driver/ADC/型号/MCP3421.md)
|
|||
|
|
|
|||
|
|
只电流的需求下，INA199A/1，INA214/均可，遗憾的多靠型号来区分IIC地址，并不适合于共用IIC多点采集的场合
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
# 计算
|
|||
|
|
前端的功耗典型值为10W，折算为5V/2A或12V/1A 采用0.1ohm=R100的采样电阻足够，对应电压范围为100~200mV 采样电阻过大会产生不必要的压降损耗
|
|||
|
|
以INA219为例，PGA = /8 时满量程为±320mV
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|