4N23A

Overview

The 4N23A is a single-channel transistor output optocoupler manufactured by TT Electronics/Optek Technology. It features an NPN phototransistor output and is housed in a TO-78-6 metal can package for through-hole mounting. The device provides electrical isolation with a maximum insulation voltage of 1000 Vrms. Key electrical parameters include a maximum collector-emitter voltage of 35 V, a maximum collector current of 50 mA, and a typical forward voltage of 1.3 V at a forward current of 10 mA. The component exhibits rise and fall times of 15 µs and operates within a temperature range of -65°C to 125°C.

Feature Summary

• Provides galvanic isolation between input and output circuits using an LED and phototransistor configuration.
• Features a hermetic TO-78-6 metal can package designed for high reliability and environmental stability.
• Offers direct interface capability with standard logic families due to compatible input voltage levels.

Applications

• Isolation of control signals in industrial automation systems
• Interface circuits connecting microprocessors to power switching stages
• Signal transmission across isolated ground planes in measurement equipment

Procurement Notes

Verify the specific suffix designation (e.g., TX, TXV) against the required military or commercial grade specifications, as these indicate variations in testing standards and quality assurance protocols. Confirm that the TO-78-6 metal can package aligns with the mechanical constraints of the target PCB layout. Ensure compliance with relevant RoHS directives if the application requires restricted substance adherence, noting that some variants may have different regulatory statuses.

Selection Notes

Select this component when high reliability and hermetic sealing are critical for the application environment. The TO-78-6 package offers superior protection against moisture and contaminants compared to plastic packages. Consider the 1000 Vrms isolation rating for applications requiring robust separation between high-voltage and low-voltage domains. Evaluate the 15 µs switching speed to ensure it meets the timing requirements of the signal transmission path.

Part Context

The 4N23A belongs to the 4N2x series of transistor output optocouplers produced by TT Electronics/Optek Technology. This series is widely recognized for its use in general-purpose isolation applications where reliability is paramount. The 4N23A specifically distinguishes itself with its hermetic metal package, making it suitable for harsh environments where standard plastic encapsulated devices might fail. It serves as a foundational component in legacy and high-reliability circuit designs.

Replacement Considerations

Public confirmed substitute part numbers: 4N23, 4N23ATX, 4N23ATXV.

FAQ

What is the maximum insulation voltage of the 4N23A?

The maximum insulation voltage is 1000 Vrms.

Does the 4N23A have a base connection on the phototransistor?

No, the 4N23A features an NPN phototransistor output without a base terminal, unlike the 4N24A which includes a base connection.