| 摘要 |
In a photo detection arrangement, the current through a detector 10 is sensed by a series resistor Rs and amplified and amplified at 21 . The output of the amplifier is compared with a reference voltage 23 , which is chosen to correspond to an overload input applied to the detector. When the comparator 22 triggers, a latch 24 is set, which controls a switch 25 to remove the supply voltage to the detector applied to the detector by power amplifier 14 . In this way, protection is afforded to the detector 10 without recourse to a high value series resistor. Moreover, the latch provides an output to demonstrate that an overload has occurred. |
