Maxim’s MAX22191 is an industrial digital input (DI) integrated circuit that translates a 24 V DI input to a 2.4 mA (typical) current for driving optical isolators. The MAX22191 is compliant with Type 1 and Type 3 inputs, compliant with 48 V inputs with an additional resistor, and IEC 61131-2 compliant.

This device’s operating power is derived from the input signal, eliminating the need for an external power supply. This DI is ideal for high-speed inputs with a 250 ns response time, CMOS compatible test input is available to monitor diagnostics for safety, integrated thermal shutdown to protect the device, robustness for harsh industrial systems, and is capable of normal operating with input signals ranging from -60 V to +60 V.

The MAX22191 is available in a small, 6-lead SOT23 package and operates over the -40°C to +125°C ambient temperature range.