Maker Pro
Maker Pro

high current charge pump

J

Jamie

Typical pump drivers seem limited to a few dozen mA.

http://www.maxim-ic.com/appnotes.cfm/appnote_number/725

Do any charge pump drivers exist which can convert 12VDC to +/- 24VDC
at ~ 2A?

Thanks,

Michael
You simply modify the circuit with current boost transistors using the
existing circuit to drive them along with larger caps after the boost
circuit..
Basically, this involves a simply totem pole unity gain stage being
driven via the existing circuit. the Feed back for regulation starts
from the output of this stage back to the driving device.

Depending on what kind of configuration you start with will determine
if you need a single end out boost or complementary pairs.

http://www.zetex.com/3.0/pdf/ZXTC2045E6.pdf

Above is a good example of a complementary set that can handle up to
5 AMPS.

You must understand how your existing charge pump regulator works and
assist it's output with current boosting transistors before it's feed
back to it's sense input for regulation.
All you need is to enlarge the cap sizes which will be handled by the
boost transistors etc.

I remember making a cheap (-) doubled voltage source via a 555 timer
that employed current boost transistors for a larger charge pump that
other wise could not be handled via the timer alone..

This was years!!!!!!!!!!!! ago.



http://webpages.charter.net/jamie_5"
 
W

whit3rd

Typical pump drivers seem limited to a few dozen mA.
Do any charge pump drivers exist which can convert 12VDC to +/- 24VDC
at ~ 2A?

Most of these 'charge pump' devices are switch/capacitor devices,
and the power efficiency is poor (under 50% of input power is
delivered to the load).

If your output is to be 2A at +/- 24VDC, that's 100W; use a
switchmode DC/DC converter, with transformer, for that kind
of application.
 
Top