KB817A Kingbright Integrated Circuit (Dual-In-Line Packages) In Stock
The KB817A is a single-channel phototransistor optocoupler from Kingbright in a DIP-4 package, offering 80% minimum current transfer ratio, 35 V collector-emitter voltage, and UL/VDE approval for safe galvanic isolation in industrial and consumer circuits.
- Manufacturer
- Kingbright
- Package
- Dual-In-Line Packages
- Pin Count
- 4
- Lifecycle
- TRANSFERRED
- Datasheet
- KB817A Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- -30.0°C to 100.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of KB817A?
- 80% minimum current transfer ratio ensures reliable opto-coupled signal transmission across the galvanic isolation barrier
- 35 V minimum collector-emitter breakdown voltage supports a wide range of load-side logic and relay driver circuits
- UL recognized and VDE approved for use in safety-critical mains-isolated consumer and industrial equipment designs
- Single-channel DIP-4 through-hole package simplifies layout for prototyping and automated through-hole assembly
What is KB817A used for?
The KB817A is widely deployed in SMPS feedback isolation loops, microcontroller-to-relay drive circuits, PLC digital input isolation modules, and industrial sensor interfaces where galvanic separation between control and power sections is required. Its 80% minimum CTR and 50 mA maximum LED forward current handle digital switching and quasi-analog feedback signals across the isolation barrier reliably. UL recognition and VDE approval make it suitable for mains-referenced applications in consumer appliances, industrial controllers, and power conversion equipment.
What are the specifications of KB817A?
| Pbfree Code | Yes |
| YTEOL | 6 |
| Additional Feature | UL RECOGNIZED, VDE APPROVED |
| Coll-Emtr Bkdn Voltage-Min | 35V |
| Configuration | SINGLE |
| Current Transfer Ratio-Min | 80% |
| Current Transfer Ratio-Nom | 80% |
| Dark Current-Max | 100nA |
| Forward Current-Max | 0.05A |
| Forward Voltage-Max | 1.4V |
| Isolation Voltage-Max | 5000V |
| Mounting Feature | THROUGH HOLE MOUNT |
| Number of Elements | 1 |
| On-State Current-Max | 0.05A |
| Optoelectronic Device Type | TRANSISTOR OUTPUT OPTOCOUPLER |
| Power Dissipation-Max | 0.15W |
| Response Time-Max | 0.000018s |
| Surface Mount | NO |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| HTS Code | 8541.40.80.00 |
| Country of Origin | Mainland China |
What are equivalent replacements for KB817A?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What current transfer ratio and collector-emitter voltage does the KB817A optocoupler guarantee?
The KB817A guarantees a minimum current transfer ratio (CTR) of 80% and a collector-emitter breakdown voltage of at least 35 V, ensuring dependable phototransistor switching in isolated circuits. With a maximum LED forward current of 50 mA and a forward voltage up to 1.4 V, it covers standard signal isolation needs in systems operating from 3.3 V logic up to 24 V industrial supply rails.
In which opto-isolation circuit applications is the KB817A most commonly used for reliable signal coupling?
KB817A is extensively used in SMPS primary-to-secondary feedback control, microcontroller-to-relay driving, PLC digital input modules, AC zero-crossing detection, and industrial sensor isolation. Its 80% minimum CTR and 35 V VCEO enable reliable low-speed switching at LED drive currents up to 50 mA, covering both digital level translation and analog-proportional feedback in mains-isolated power and control equipment.
How do the UL recognition and VDE approval of the KB817A simplify compliance certification for mains-isolated product designs?
UL recognition and VDE approval confirm that the KB817A meets creepage, clearance, and withstand voltage requirements for basic or reinforced isolation in consumer and industrial equipment. Including a pre-certified component reduces the testing burden during product-level UL or CE marking submissions, accelerating time-to-market for designs that use the KB817A to isolate 35 V load-side circuits from mains-referenced primary sections.
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About Kingbright
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