General Description

The MAX22191 is an IEC 61131-2 compliant, industrial

digital input (DI) device. The MAX22191 translates a 24V

industrial switching signal to a 3.3V/5V CMOS-level

output, or to a 2.3mA (typ) current output for driving an

optocoupler and/or LED. Voltage thresholds and current

levels in the MAX22191 are compliant with Type 1 and

Type 3 inputs, while minimizing power dissipation. The

MAX22191 is also compliant with 48V inputs, with the

addition of external resistors.

Operating power is derived from the input signal, eliminating

the need for an external field-side power supply. A 250ns

(max) fast response time is ideal for high-speed inputs.

Additionally, a CMOS-compatible test input is available for

safety diagnostics.

The MAX22191 features robust functionality for harsh

industrial systems and is capable of normal operation with

input signals ranging from -60V to +60V. Integrated thermal

The MAX22191 is available in a small, 6-lead SOT23

package and operates over the -40°C to +125°C ambient

temperature range.

Applications

● Process Automation

● Industrial Automation

● Motor Controls

● Individually Isolated Inputs

● Current Sourcing Inputs

Benefits and Features

● High Integration for Flexible Circuit Designs

• Interfaces to Optocouplers or Digital Isolators

• Capable of Driving an Optocoupler and Status LED

• Operational as Sink or Source Digital Input

• Ultra-High Speed: 250ns (max) Propagation Delay

• Test Pulse Diagnostic

• Allows for Small Footprint TVS Surge Protection

● Reduced Power and Heat Dissipation

• Parasitically Powered from the Field Input

• Accurate ±15% Input-Current Limiting

• 100µA (typ) Quiescent Current with Optocoupler

• 96% (typ) Current-Transfer Efficiency to Optocoupler

● Robust Design

• Operates from -60V to +60V Input Voltage

• -40°C to +125°C Ambient Operating Temperature

Ordering Information appears at end of data sheet.

19-100229; Rev 1; 10/20

Click

here to ask about production status of specific part numbers.

MAX22191

Ultra-Low-Power, Parasitically Powered

Digital Input

Simplified Block Diagram

IN

REXT

2.3mA

INT

REF

OUT

MAX22191

TEST

GND

EVALUATION KIT AVAILABLE