KB817B Kingbright Integrated Circuit (Small Outline Packages) In Stock
The Kingbright KB817B is a 4-pin DIP single-channel optocoupler with 35 V collector-emitter breakdown, 50 mA max LED forward current, and 130% minimum current transfer ratio. UL Recognized and VDE Approved for signal isolation in industrial and consumer applications. In stock with worldwide shipping.
- Manufacturer
- Kingbright
- Package
- Small Outline Packages
- Pin Count
- 4
- Lifecycle
- ACTIVE
- Datasheet
- KB817B 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 KB817B?
- 35 V collector-emitter breakdown voltage and 130% minimum CTR enable reliable output transistor drive in wide-range isolated signal switching and relay driver designs
- UL Recognized and VDE Approved safety certifications simplify regulatory compliance for industrial automation, SMPS feedback, and appliance isolation applications
- 50 mA max LED input current with 100 nA maximum dark current delivers high signal-to-noise ratio in low-level isolated logic and analog circuits
What is KB817B used for?
The KB817B is widely used for signal isolation between high-voltage control circuits and low-voltage microcontroller inputs in industrial PLCs, motor drives, and SMPS opto-feedback paths. Its 35 V collector-emitter breakdown voltage and 130% CTR make it suitable for optically isolating relay drivers, zero-crossing detectors, and inter-board logic level converters. UL and VDE certifications simplify regulatory approval for consumer appliances and industrial control equipment.
What are the specifications of KB817B?
| Pbfree Code | Yes |
| Reach Compliance Code | Unknown |
| YTEOL | 7.5 |
| Additional Feature | UL RECOGNIZED, VDE APPROVED |
| Coll-Emtr Bkdn Voltage-Min | 35V |
| Configuration | SINGLE |
| Current Transfer Ratio-Min | 130% |
| Current Transfer Ratio-Nom | 50% |
| 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 | Small Outline 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 KB817B?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
For an SMPS opto-feedback design, what current transfer ratio and breakdown voltage does KB817B provide at typical LED input current?
The KB817B delivers a minimum 130% current transfer ratio with a 35 V collector-emitter breakdown voltage, making it well suited for switch-mode power supply feedback loops. With 50 mA maximum LED forward current and only 100 nA dark current leakage, it provides clean isolated feedback signals across a wide output load range.
What safety certifications does KB817B carry, and how do they support compliance in industrial panel designs?
The KB817B is UL Recognized and VDE Approved, meeting North American and European safety standards for optocoupler isolation in industrial equipment. These certifications support IEC and UL 508A compliance for control panel designs, reducing approval time. The 35 V collector-emitter breakdown voltage and 50 mA LED input rating suit 24 V industrial bus signal isolation.
In a relay driver isolation circuit, how does KB817B's NPN output transistor support switching loads up to 35 V?
The KB817B's NPN transistor output withstands collector-emitter voltages up to 35 V, enabling direct optical isolation of relay coils at 5 V to 24 V supply rails. With a minimum 130% current transfer ratio, a 10 mA LED input drives adequate base current to saturate the transistor at 50 mA, switching relay loads without additional driver stages.
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Why Buy from FindMyChip
About Kingbright
Kingbright is a leading electronic component manufacturer. FindMyChip sources Kingbright ICs directly from authorized China distributors, offering competitive pricing and reliable stock.
In Stock · 24h Response · Worldwide Shipping
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