Timeline for What is the reason my ULN2003A overheats?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Mar 7, 2015 at 15:34 | comment | added | Dwayne Reid | Be aware that there may also be bypass capacitors inside the fans. Same issue as above. The fix is to install inductors between the driver output & fan input. | |
| Jul 7, 2014 at 18:45 | vote | accept | haimg | ||
| Jul 1, 2014 at 7:18 | comment | added | Andy aka | @haimg so now maybe you should consider replacing the ULN with something that is a more efficient driver. These are darlingtons and are always going to drop about 1V when conducting 200mA - that's 200mW per channel. You need to use MOSFETs for this to run cool. Like this google.co.uk/… - it has 0.5 ohms on resistance therefore only 20mW per channel (TPIC2701) or individual mosfets. | |
| Jun 30, 2014 at 22:10 | comment | added | haimg | Thanks for your answer. Capacitors were indeed not needed and harmful. I removed them. The situation has improved, but just. E.g. ULN2003A is not scorching hot, just very hot. And of course once I raise the pwm duty cycle, it becomes barely warm. | |
| Jun 29, 2014 at 19:27 | history | edited | Andy aka | CC BY-SA 3.0 |
typos
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| Jun 29, 2014 at 18:53 | history | answered | Andy aka | CC BY-SA 3.0 |