hippy
Ex-Staff (retired)
Anyone with experience of charge pumps want to cast an eye over this ...
Ignoring diode drops throughout, with O1 Low, C1 charges up to +5V. With O1 then taken high and O2 low, the voltage at C1+ is 5V plus the 5V C1- is raised to, so it dumps +10V charge into C2. With O2 taken high, it then dumps 15V into C3.
As best I can see O2 can be driven as the inverse of O1. This could therefore be done with any PICAXE with PWMOUT and an inverter, or a 14M in full-bridge mode ( which is even better because there's a programmable delay between O1 going low before O2 goes high etc ).
Am I missing anything obvious ? How would I even go about choosing an ideal PWM frequency ?
My actual target voltage is 10.5V-11.5V, so guess I would drop the final voltage through however many diodes it would need.
Edited by - hippy on 23/05/2007 03:46:16
Code:
-.- +5V
|
`---|>|----.----|>|----.----|>|----.----> +15V (ish)
__|__ + __|__ + __|__ +
C1 ==.== C2 ==.== C3 ==.==
| | _|_ 0V
O1 >-------' |
O2 >-------------------'
As best I can see O2 can be driven as the inverse of O1. This could therefore be done with any PICAXE with PWMOUT and an inverter, or a 14M in full-bridge mode ( which is even better because there's a programmable delay between O1 going low before O2 goes high etc ).
Am I missing anything obvious ? How would I even go about choosing an ideal PWM frequency ?
My actual target voltage is 10.5V-11.5V, so guess I would drop the final voltage through however many diodes it would need.
Edited by - hippy on 23/05/2007 03:46:16
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