Digital Isolators

Introduction to HCPL-0931-500E Isolator

The HCPL-0931-500E is a part of the family of highly integrated optocouplers from TI. It is an isolator in the form of a small surface-mounted package with high-speed digital input/output capabilities. It is designed to enable low voltage isolation in digital systems. This isolator provides a high level of insulation that meets or exceeds VDE 0884, EN 50178 and UL 1950 standards. It has a high dielectric strength of 2,000 V rms, and a good common-mode and transient immunity.

Application Field and Working Principle of HCPL-0931-500E

The HCPL-0931-500E isolator is typically used in more demanding applications than the standard optocoupler, due to its improved isolation properties and higher switching speed. It is suitable for digital isolation applications requiring high PZT (phototransistor) CTR, low signal delays, and minimal propagation delay times. It is excellent for data transmission applications where a low-power AC output allows for isolated transfer of irregular clock signals from low to medium frequencies. An example application is using the HCPL-0931-500E for linearizing analog-to-digital (A/D) converters and isolating digital signal processing systems such as position sensors, linear amplifiers, drive-by-wire systems, and serial data communication.

The HCPL-0931-500E has an integrated Phototransistor driver, which is optically coupled to a fixed threshold photodetector. The trigger threshold of the photodetector can be adjusted to match the rise/fall times of the input when using the appropriate input resistor. This allows the isolator to trigger with a low level of common mode noise between the input and output. The isolator is designed to react to rising and falling edges of the input signal and will not produce an output until a certain trigger level is reached. The output of the isolator will drive the AC output according to the input levels and the operation of the isolator. In addition, the HCPL-0931-500E is designed to be immune to external noise, and it provides high common mode noise rejection to reduce false triggering of the output.

Conclusion

To sum up, the HCPL-0931-500E digital isolator from TI is a versatile and high-speed device, capable of providing extremely reliable long-distance signal isolation for digital systems. By utilizing the high dielectric strength, common mode rejection, and low trigger threshold, it is able to operate in more demanding applications while providing high levels of noise immunity and signal accuracy. The HCPL-0931-500E is therefore the perfect choice for digital isolation applications that require a high level of safety and performance.