PS2621 datasheet(33/38 Pages) NEC

33 / 38 page

CTR vs. IF Characteristics

As shown in Figure 8, the CTR of a single-transistor output optocoupler (such as the PS2501 and PS2505 optocouplers) is at

most 20% in a low-current area (e.g. IF = 0.1 mA). However, the CTR of a Darlington-transistor output optocoupler (such as the

PS2502 and PS2506 optocouplers) can be greater than 200% in a low-current area (e.g. IF = 0.1 mA).

Figure 24 shows the CTR vs. IF characteristics of the PS2502 and PS2506 optocouplers.

Forward Current IF (mA)

CONCLUSION

Demand for optocouplers featuring higher insulation and noise elimination is steadily increasing. At the same time, various

problems (change of characteristics by ambient temperature and time elapse) will occur in their circuit design. We hope this

manual will be helpful in solving such problems.

Figure 24. CTR vs. IF Characteristics (Standard Value)

(PS2502, PS2506)

7000

6000

5000

4000

3000

2000

1000

0.05 0.1

0.5

Standard characteristics

VCE = 2V

PS2621 数据表(PDF) 33 Page - NEC