Skip to Content
  1. All products
  2. 🧬 Discrete Components
  3. 🔳 ICs, Transistors & Mosfets
  4. PC817 Phototransistor Output Optoisolator IC
  5. 🔳 ICs, Transistors & Mosfets
Pricelist: Retail Price (B2C) Pricelist
Pricelist: Retail Price (B2C) Pricelist
PC817 Phototransistor Output Optoisolator IC

PC817 Phototransistor Output Optoisolator IC

(0 review)
SpecificationDetails
Package TypeDIP-4 (Through-hole)
Input Forward Current50 mA (Max)
Collector-Emitter Voltage35 V (Max)
Isolation Voltage5000 Vrms
Current Transfer Ratio50% to 600% (CTR)
Response Time4µs to 18µs
Operating Temp-30°C to +100°C
Price
₹ 8.47 ₹ 8.47
(Tax included)

Barcode: 72551464

Product Description

The PC817 IC is engineered for high-reliability signal switching and noise suppression. When current flows through the internal IR LED, it emits light that triggers the phototransistor to become conductive. Because the communication is purely light-based, there is no physical path for electricity to flow between the input and output pins. This makes the PC817 an essential component in Switching Mode Power Supplies (SMPS), logic circuit isolation, and industrial I/O systems where electrical noise is a constant challenge.

Key Features

  • High Isolation Voltage: Capable of withstanding up to 5000 Vrms, ensuring maximum safety for the user and the control hardware.

  • Compact DIP-4 Footprint: Standard spacing makes it compatible with breadboards, perf-boards, and automated PCB assembly.

  • No Mechanical Parts: Unlike a relay, the optocoupler has no moving parts, meaning it operates silently and has an almost infinite switching lifespan.

  • Low Power Drive: The internal LED can be triggered by standard microcontroller GPIO pins (with a suitable resistor).

  • High-Speed Switching: Fast enough for PWM signals and standard serial communication isolation.

Technical Details

  • Collector Current: 50 mA (Maximum continuous load).

  • Power Dissipation: 200 mW total power handling.

  • Internal Configuration: 1-Channel (Single optocoupler per IC).

Prototyping and Engineering Tips from Robogears

  • Pin 1 Identification: Look for a small circular dimple on the top of the IC. That corner is Pin 1 (Anode of the internal LED). Wiring the LED backward will not damage the chip but will prevent it from switching.

  • The Input Resistor: Never connect the input pins (1 and 2) directly to power. You must use a current-limiting resistor (typically 220Ω to 470Ω for 5V signals) to prevent the internal IR LED from burning out.

  • Understanding CTR: The Current Transfer Ratio (CTR) means that if you put 10mA into the LED, the transistor side can only reliably handle a certain percentage of that current (e.g., 5mA at 50% CTR). Do not try to drive a motor or a large solenoid directly with a PC817; instead, use the PC817 to trigger a larger Power Transistor or MOSFET.

  • Common Ground Isolation: To get the full benefit of isolation, do not connect the grounds of the two circuits together. If the input ground and output ground are the same, a high-voltage surge can still find a path to your controller, bypassing the optical gap.

Package Includes

  • 1 x PC817 DIP-4 Transistor Output Optocoupler

Disclaimer

This component is designed for signal-level isolation. While it can handle high isolation voltages, the output transistor is limited to low-current switching (50mA). Overloading the output side will result in permanent failure of the IC.