| ??? 01/22/06 06:56 Read: times |
#108031 - problem with port current |
hi frds,
i have problem with port current i think.but please tell me solution. i have 89c51 mc and programing is such that port P1 is high for 18 sec and low for other 18 sec.i need to amplify the port current to drive 2 dc motors.port current is very feable(10mamps). when i connected the port out put to bc548 transistor to amplify the signal so as to feed the the two darling ton pair circuits. wat i observed is that out put of port even it has changed but led which i have connect to collector is constantly glowing and not blinking for 18secs wat would be the problem. please specify solution |
| Topic | Author | Date |
| problem with port current | 01/01/70 00:00 | |
| How about the waveforms at the port pin? | 01/01/70 00:00 | |
| yes port waveform is correct | 01/01/70 00:00 | |
| post your schematic | 01/01/70 00:00 | |
| Biasing | 01/01/70 00:00 | |
| Motor Controller | 01/01/70 00:00 | |
| Come on... | 01/01/70 00:00 | |
Transistor turn off | 01/01/70 00:00 |