HCPL0631: High-Performance Dual-Channel Optoisolator by onsemi | Features & Applications
HCPL0631: onsemi's High-Speed Dual-Channel Optoisolator with 3750Vrms Isolation
The HCPL0631 from onsemi represents the gold standard in optoisolation technology, delivering unmatched performance for critical isolation applications. As a dual-channel, open-collector optocoupler with 3.75kVrms isolation, this component continues to be specified in designs despite its obsolete status due to its exceptional reliability and technical specifications. This comprehensive guide explores every aspect of the HCPL0631, from its electrical characteristics to its diverse industrial applications.
Technical Deep Dive: HCPL0631 Specifications
Isolation and Safety Features
The HCPL0631 provides 3750Vrms of reinforced isolation (tested for 1 minute per UL1577), making it suitable for:
- Medical equipment requiring patient-protective isolation
- Industrial control systems with high-voltage sections
- Power supply feedback circuits
With 5kV/ s common-mode rejection, it maintains signal integrity even in electrically noisy environments like motor drives and power inverters.
High-Speed Performance Metrics
Engineers value the HCPL0631 for its 10Mbps data transmission capability, supported by:
- Propagation delay: 75ns maximum (tpLH/tpHL)
- Fast rise/fall times: 50ns/12ns typical
- Channel-to-channel skew: 50ns maximum
These characteristics make it ideal for digital signal isolation in:
- Fieldbus communications (Profibus, DeviceNet)
- Encoder interfaces
- PLC digital I/O modules
Electrical and Thermal Characteristics
| Parameter | Value |
|---|---|
| Input Forward Voltage | 1.75V (max) |
| Output Current | 50mA per channel |
| Supply Voltage | 4.5V to 5.5V |
| Operating Temperature | -40 C to +85 C |
Package and Mechanical Details
The 8-SOIC Tall package (3.90mm width) offers:
- 8mm creepage distance for high-voltage safety
- Surface-mount compatibility for automated assembly
- Moisture Sensitivity Level (MSL): 1 (unlimited floor life)
Design Considerations
When implementing the HCPL0631:
- Use 10-20mA input current for optimal LED lifetime
- Include 0.1 F bypass capacitors near supply pins
- For open-collector outputs, calculate pull-up resistors using:
R = (Vcc - Vol)/Iol
Alternatives and Cross-References
For current-production alternatives, consider:
- HCPL-063A (similar specifications)
- 6N137 (single-channel, higher speed)
- ISO7720 (digital isolator, non-optical)
Purchasing and Availability
While obsolete, the HCPL0631 remains available through:
- Authorized distributors' remaining stock
- Specialized obsolete component suppliers
- Aftermarket channels (with authenticity verification)
For engineers requiring the unique combination of dual-channel isolation, high speed, and proven reliability, the HCPL0631 remains a compelling choice despite its obsolescence status. Its technical specifications continue to meet demanding isolation requirements across industrial, medical, and communications applications.