| ??? 08/26/05 06:17 Read: times |
#100113 - MCU-resistor-NPN Responding to: ???'s previous message |
hi,
Erik Malund said:
I would use 1k to make saturation, at least, likely.
Here we have a problem. My tests with some Atmel derivatives show that when MCU drives base of NPN transistor with logic "1" then it cannot open transistor when its base resistor is below ~4k7. For example, such scheme works stable with 10k resistor and does not work with 1k0 at all. I have explained it here: http://www.8052.com/forum/read.phtml?id=74217 Regards, Oleg |
| Topic | Author | Date |
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| MCU-resistor-NPN | 01/01/70 00:00 | |
| 8051 is open drain ! | 01/01/70 00:00 | |
| not good idea | 01/01/70 00:00 | |
| totally wrong ! | 01/01/70 00:00 | |
| This I would take with a grain of salt. | 01/01/70 00:00 | |
| But nevertheless totally unsuited! | 01/01/70 00:00 | |
| Where in Atmel errata or other informati | 01/01/70 00:00 | |
| That's standard performance of quasi bi. | 01/01/70 00:00 | |
| Try This | 01/01/70 00:00 | |
updated | 01/01/70 00:00 |