2
\$\begingroup\$

Is there any known approaches to regulate HV in the range of 1500-6000V in order to eat noise? Low-side regulation is a possibility.

The idea is to get ~100V higher voltage than needed, and then regulate it down with a linear regulator in order to achieve lower ripple noise. Supply current is 100µA-6mA, so this 100V regulation delta will dissipate not too much power.

\$\endgroup\$
5
  • \$\begingroup\$ There are expensive IGBTs rated for 3700 DC, else you might consider large triode tubes. There is no cheap way to do this. \$\endgroup\$
    – user105652
    Jul 6, 2019 at 21:13
  • \$\begingroup\$ I suppose you could float a regulator circuit on a stack of zener diodes to ground. You'd get the zener noise but it would allow you to use an IC that isn't rated for your supply voltage - maybe a 400 V MOSFET. You'd probably have to be careful to disconnect the IC on switch-off so that when the zeners stop regulating the IC isn't exposed to the full voltage. Definitely needs careful design. \$\endgroup\$
    – Sean
    Jul 6, 2019 at 21:17
  • 1
    \$\begingroup\$ Actually the regulator itself only needs to see the variation, plus some overhead -- so, if the variation is over a 100V span, the regulator only needs to see 120V or so. Powering the regulator is another matter, though. \$\endgroup\$
    – TimWescott
    Jul 6, 2019 at 21:48
  • 1
    \$\begingroup\$ Tim's and Sean's comments are valid, I have done it, since regulators only really need a virtual ground, you can find a 150v rated adjustable LDO and do what your trying to do. You can make a virtual ground with a resistor divider and capacitor to smooth since the regulator typically drops micro amps to ground. \$\endgroup\$
    – MadHatter
    Jul 6, 2019 at 21:53
  • \$\begingroup\$ Also consider looking into the type of switch mode supplies used for photon multipliers, I forget the type but they can typically regulate 1kV with < 1mV of noise. \$\endgroup\$
    – MadHatter
    Jul 6, 2019 at 21:55

1 Answer 1

1
\$\begingroup\$

From my comments, with credit to @Sean and TimWescott (Since they have not yet answered).

If you only want to knock the peak voltage down by ~100V, there is no need for a super high voltage regulation system. Typical modern linear regulators really only require a "reference" for ground since they often sink far less then 1mA. Look for low "Quiescent Current" regulators often designed for low power.

To create a virtual ground reference you could do it two ways:

  1. Use a resistor voltage divider with an RC filter to create a short term steady ground based on the input voltage. This is ideal if you have good long term voltage stability from something like a SMPS and you want to reduce ripple.
  2. As Tom noted, you can use a stack up of Zener diodes to create a known ground potential, but you create a risk of over voltage if your incoming supply has a large variation, also there will be some noise from the Zener diodes, but probably still cleaner then option 1.

NOTE: Values in schematic are only for reference, they need adjusting based on your voltages, currents and regulator of choice. For the regulator, check out the TL783 or LR8N8, both are good for 450V.

schematic

simulate this circuit – Schematic created using CircuitLab

schematic

simulate this circuit

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.