| punchpeanut |
Hi again. I have seen circuits similar to this one in several places. U1 is a NE555 timer, used to invert 12V. On one website (the one I got this pic from), the author stated a max current of 280mA. That's sufficent for my needs. On the ESP site, a similar one is stated as having max current of 30mA. How much can I really expect out of one of these circuits?
Thanks. |
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| peranders |
I have a hunch of that Rod is closer to the truth :nod:
You can simulate this in LTSpice (freeware) and use a square wave source with a resistor in series to limiting the current. Just add a load also. Then you can see how the wave form will look like. You can also measure currents. This design to create negative voltage is rather ineffective. |
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| jehaupt |
use this IC to invert a plus supply: ICL7662, available from www.newark.com.
Jim |
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| promitheus |
Hi,
I have never measured that but I would say not more than 50 mA. ICs like the 555 canīt deliver much current. |
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| ACD |
As I recall:
I-Sink: 50mA
I-Source: 100/200 mA |
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| promitheus |
| ACD nice website you got there. |
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| roadkill |
| This question's not easy to answer unless you know what kind of ripple you can tolerate at the output, typical of any unregulated supply. Use an LDO at the output if in doubt. And, as peranders has suggested, simulate. |
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