Features
Guaranteed 20 mA loop parameters
Data input compatible with LSTTL, TTL and CMOS
Logic
Internal shield for High Common Mode rejection
20 kBaud data rate at 400 metres line length
Guaranteed On and O output current levels
Safety approval
UL Recognized -3750 V rms for 1 minute
CSA Approved
Optically coupled 20 mA current loop receiver,
HCPL-4200, also available
Applications
Isolated 20 mA current loop transmitter in:
Computer peripherals
Industrial control equipment
Data communications equipment
CAUTION: It is advised that normal static precautions be taken in handling and assembly
of this component to prevent damage and/or degradation which may be induced by ESD.
A 0.1 μF bypass capacitor connected between pins 8 and 5 is recommended.
Description
The HCPL-4100 optocoupler is designed to operate as a
transmitter in equipment using the 20mA current loop.
20 mA current loop systems conventionally signal a
logic high state by transmitting 20 mA of loop current
(MARK), and signal a logic low state by allowing no
more than a few milliamperes of loop current (SPACE).
Optical coupling of the signal from the logic input to the
20 mA current loop breaks ground loops and provides
very high immunity to common mode interference.
The HCPL-4100 data input is compatible with
LSTTL, TTL, or CMOS logic gates. The input integrated
circuit drives a GaAsP LED. The light emitted by the LED is
sensed by a second integrated circuit that allows 20 mA
to pass with a voltage drop of less than 2.7 volts when
no light is emitted and allows less than 2 mA to pass
when light is emitted. The transmitter output is capable
of withstanding 27 volts. The input integrated circuit
provides a controlled amount of LED drive current and
takes into account any LED light output degradation. The
internal shield allows a guaranteed 1000 V/μs common
mode transient immunity.
Functional Diagram
HCPL-4100
Optically Coupled 20 mA Current Loop Transmitter
Data Sheet
Lead (Pb) Free
RoHS 6 fully
compliant
RoHS 6 fully compliant options available;
-xxxE denotes a lead-free product
