Is it possible to bounce 5 volts up to 12 volts to provide maybe a mA of output current using a single 4093 section?
- posted
7 years ago
Is it possible to bounce 5 volts up to 12 volts to provide maybe a mA of output current using a single 4093 section?
Yup. Schmitt oscillator, three parallel buffers, voltage multiplier riding on +5. Might be a bit over 12 volts.
I could draw it if requested.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
But I only have one section... :(
Feed the classic Cockcroft-Walton from the 4093
Should be ok for 1mA load. Look up old data sheets that has info on the CMOS RdSon, simulate or test
Cheers
Klaus
Requested. ...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et |
OK, but a real CD4096 will be a little wimpy as a charge pump. Might work, might droop too much. An HC series part would be a tougher driver. HC132 or HC14, something like that.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Should I post it to sci.electronics.basics for you?
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Nope. See Pg 2 and 3. Typical output current with Vdd=5V is 0.88ma high and 2.21ma low at
25C. About half that at temperature extremes. If you follow the NAND with a voltage tripler or quadrupler, you'll get 1/3 or 1/4th of the current ratings in output current.See "gated oscillator" on Pg 4 of the above datasheet.
However, you can buffer the output with an emitter follower and easily get the necessary current.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
OOOOH SNAP
Yes, please. ...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et |
(Oops. I skipped a line on the data sheet. It should be 0.88ma both high and low. Still won't work.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
A single emitter follower would need a very low value pulldown resistor. A PNP-NPN follower would work, but will cost about 1.5 volts p-p swing.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
oscillator driving a 3 stage cockroft-walton?
-- \_(?)_
You're running at 5V. You can't upgrade it to 74HC? That will get you the needed current capacity. Or 74AC even (beware the risetime though).
Tim
-- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design
The low side of the C-W multiplier can be parked on +5, so it only needs 2 stages. The first 5 volts is free.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
I'm picturing an oscillator, drivers, into cap and then, two more sections or diode's and caps... all referenced to 5V.
George H. (But sure put a scribble pic on SEB. :^)
Y'er right. I thought that the multiplier was a half wave device and only drew current on the positive cycle. That way the load acts as a pull down. However, that's wrong as it conducts on both the positive and negative parts of the cycle. Sorry(tm).
Do you agree that the 4093 will NOT be able to supply 1ma output by itself?
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
Probably not, if it's one section of an original CD4093. They are pretty wussy, especially with a 5 volt supply.
It would work fine with a 12 volt supply!
-- John Larkin Highland Technology, Inc lunatic fringe electronics
OK, scrawls-r-us.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
There used to be a 74HC4093. Does that series still exist?
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.