| ??? 11/28/10 09:26 Read: times |
#179693 - Leakage current analysis Responding to: ???'s previous message |
Going by the block diagram again, if the base of the phototransistor is floating, that is no pull down resistor, then it will not be off even when the input LED is off.
And that leakage current (Iceo) multiplied by the Darlington gain will lead to substantial "off" state current at the output. |
| Topic | Author | Date |
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| 3.3V Regulator Idea | 01/01/70 00:00 | |
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| It is a SOURCE board ... | 01/01/70 00:00 | |
| Hhm, leakage currents? | 01/01/70 00:00 | |
| Solution in sight | 01/01/70 00:00 | |
| LED tester shows bad design/bad parts | 01/01/70 00:00 | |
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| LED tester shows bad design/bad parts | 01/01/70 00:00 | |
| I wouldn't rely on anything published by NI | 01/01/70 00:00 | |
| crying wolf again?? | 01/01/70 00:00 | |
| NI is not a fly-by-night-operator | 01/01/70 00:00 | |
| No question about that | 01/01/70 00:00 | |
| The "crying wolf" is right here... | 01/01/70 00:00 | |
| I also say it... | 01/01/70 00:00 | |
Leakage current analysis | 01/01/70 00:00 | |
| Also, the voltage across the load.... | 01/01/70 00:00 |