??? 08/26/05 08:37 Read: times Msg Score: 0 +1 Good Answer/Helpful -1 Answer is Wrong |
#100124 - not good idea Responding to: ???'s previous message |
hi,
Peter Dannegger said:
To drive a transistor, put the base direct on the 8051 port pin and a resistor from base to VCC.
...and it will work with pins of port 0 only. With others ports you have a good chance to burn base-emitter of transistor each time when there is 0-to-1 transition on a pin. Why? Because strong pull-up pFET1 is turned on for 2 osc. periods. Read http://www.8052.com/forum/read.phtml?id=93728 Here is corrected schematic by Michael: http://www.8052.com/forum/read.phtml?id=93726 Regards, Oleg |
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updated![]() | 01/01/70 00:00 |