Radiation Tolerant Phototransistor Hermetic Surface Mount Optocoupler

The OLS249 consists of an LED that is optically coupled to an N-P-N silicon phototransistor, which is mounted and coupled in a custom hermetic surface mount technology (SMT) leadless chip carrier (LCC) package.

The low input current makes the OLS249 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 current transfer ratio (CTR) degradation characteristics due to radiation exposure. Special electrical parametric selections are available upon request.


  • Hermetic SMT package
  • 1500 VDC electrical isolation
  • High CTR
  • Small package size
  • High reliability and rugged construction
  • High-reliability screening available
  • Radiation tolerant
Data Sheets OLS249 Data Sheet OLS249_202682E.pdf (389 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)
White Paper Discussion of RGA Test for Moisture Content for Isolink Optocouplers WP_RGA_2017_Feb.pdf (123 KB)
ProductName : OLS249
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 Hermetic Ceramic LCC
Radiation Tolerant : Yes
No Base Connection :
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