Current Loop Application Note
Table of Contents

1.0	Introduction
2.0	The Basics of Current Loop
	2.1	Full-duplex 20 mA Circuit
	2.2	The Simplex 20 mA Circuit
	2.3	Problems with 20 mA Current Loop
	2.4	Current Regulation in Current Loops
		2.4.1	Constant Current Generator Current Source
		2.4.2	Transmitter Current Limiter
		2.4.3	Receiver Current Limiter
3.0	Current Loop Interface Connections
	3.1	Connection to an Active Current Loop Port
	3.2	Connection to an Passive Current Loop Port
	3.3	Interconnection of 2 Current Loop Converters
4.0	What Isn't Digital Current Loop
	4.1	4 to 20 mA Analog Current Loop
	4.2	Hart® 4 to 20 mA Current Loops