Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.arch.embedded > #28985

Re: high voltage charge pump

Show all headers | View raw

On 12/30/19 8:53 AM, Hul Tytus wrote:
>     Anyone familiar with a high voltage charge pump designed as a step down
> power supply? The voltage is between 175 & 200. Numerous high voltage
> versions exist using inductors, (Onsemi has one that is "self supplied"
> which is attractive) but not a one that works with just a capacitor. Are
> there any out there I've missed?
> 
> Hul
> 

Most charge pump designs will multiply voltages (invert or step up), not 
divide.

While a step down configuration is possible, I think it requires much 
more careful choices of values and control law to keep the output from 
getting too high of a voltage.

Also, all charge pumps that I know use MULTIPLE capacitors, they 
generally work moving charge in a controlled way, so generally require 
at least one 'moving' capacitor to transfer with and one fixed output 
capacitor to store the output charge.

One reason you don't generally use a charge pump for step down is that 
charge pumps are best used at very low current. For very low current 
steo down, the simple linear regulator is normally a perfect solution 
and often is as efficient or even better than a switched capacitor step 
down system.

Back to comp.arch.embedded | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

high voltage charge pump Hul Tytus <ht@panix.com> - 2019-12-30 13:53 +0000
  Re: high voltage charge pump Richard Damon <Richard@Damon-Family.org> - 2019-12-30 10:30 -0500
    Re: high voltage charge pump Hul Tytus <ht@panix.com> - 2019-12-31 16:35 +0000
      Re: high voltage charge pump Richard Damon <Richard@Damon-Family.org> - 2019-12-31 12:47 -0500
      Re: high voltage charge pump Rick C <gnuarm.deletethisbit@gmail.com> - 2019-12-31 16:30 -0800

csiph-web