Radiation Tolerant, Phototransistor Optocoupler for Hybrid Assembly

The OLI249 is designed especially for hybrid applications that require optical isolation with high current transfer ratio (CTR) and low saturation VCE. Each OLI249 consists of an LED and N-P-N silicon phototransistor that is mounted and coupled in a miniature custom ceramic package. The low input current makes the OLI249 well suited for direct Complementary Metal Oxide Semiconductor (CMOS) to Low Power Schottky Transistor-Transistor Logic (LSTTL)/TTL interfaces.

Electrical parameters are similar to the JEDEC registered 4N49 optocoupler, but with better CTR degradation characteristics due to radiation exposure.

Device mounting is achieved by standard hybrid assembly with non-conductive epoxies. Gold or aluminum wire bonding can be used to make electrical connections for maximum placement flexibility.

Special electrical parametric selections are available upon request.


  • Current transfer ratio (CTR) is:
    • Guaranteed over –55 °C to +100 °C ambient temperature range
    • High at low input current—200% at IF = 2 mA over temperature
    • Comparable to Darlington output, but with low saturation VCE = 0.15 V typical
  • 1500 VDC electrical isolation
  • Small footprint for hybrid device
  • More radiation tolerant than 4N49 (contact Isolink for more information)
  • Similar to 4N4X type optocouplers
  • High reliability and rugged construction
  • Custom package is available
Data Sheets OLI249 Data Sheet OLI249_202467F.pdf (274 KB)
Application Notes Skyworks Optocouplers vs. Pulse Transformers Optocouplers_vs_Pulse_Transformers_204659A_AN.pdf (108 KB)
White Paper Optocouplers for the Hybrid industry WP_Optocouplers_for_the_Hybrid_industry.pdf (322 KB)
ProductName : OLI249
Memo :
Condition : CTR @ IF = 1 mA
CTR Min. : 200
CTR Max. : 1200
BVCEO (V) : 40
Vcc Max. (V) :
Switching Time (μs) : 25
Isolation @ VDC 1 Sec. : 1500
Package Photo :
Package Info : 6-Lead Ceramic Carrier Chip for Hybrid Assembly
Radiation Tolerant : Yes
No Base Connection :
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