0
\$\begingroup\$

I am designing a PCB that has high voltage (DC) on it. It will be located on a CubeSat (so, space).

The PCB (HV-PCB) will receive the HV (3 kV max) from a DC-DC converter through a Coax cable; the purpose of this PCB is to filter the HV through an RC circuit and then distribute it using connectors and cable to 16 detectors (they are on another board, see below) to provide them with bias.

The HV-PCB will also host another filtering circuit for another HV (<300 V) and will also distribute it to the detector board using connectors and cables.

a) are there particular materials that I should consider for the PCB?
b) can the two circuits live together on the same HV-PCB? My guess is that the best thing to do is to have the components well separated (spatially) on the PCB.
c)in terms of components, is there a particular family of components that I should look into, that are suited for my application? (HV, space).

In general, do you have references (pdfs, youtube videos, tutorials, standards) that might be useful for the design of a HV PCB?

Thanks for the help!

EDIT: tried to be more specific with my questions; on the other hand, I still need to stay generic, since I am asking for some guidelines/suggestions. Hope it is good enough.

\$\endgroup\$
  • \$\begingroup\$ Will the HV circuits be active during the launch? Hopefully not, low pressures cause more difficulty than either normal earth pressure or a vacuum. The phenomenon is called corona discharge, and can happen at fairly low voltages at certain air pressures. \$\endgroup\$ – Mattman944 Aug 20 '19 at 12:33
  • \$\begingroup\$ No, the HV will not be active during launch. The detector will start operations when in orbit, so everything will be shut-down! \$\endgroup\$ – Cesco Aug 20 '19 at 12:35
  • \$\begingroup\$ CTI of the PCB and lacquer, pollution degree of the product, creepage for whatever the rated max voltage is, clearance for max impulse voltage and altitude if you are going to put it really high (avionics or some telescope at the top of some mountain in Chile). \$\endgroup\$ – winny Aug 20 '19 at 13:20
1
\$\begingroup\$

The main things to consider are the required spacing around any conductors carrying high voltage, and avoiding pointy shapes on high voltage lines.

You can look at online calculators such as...

http://www.creepage.com/

...for estimated spacing between conductors.

Also consider the dielectric thickness between layers on the PWB.

For the design to be reliable obviously pick components that are rated beyond the worst cast voltages you plan to put on them. The more margin you have the more reliable the circuit will be.

| improve this answer | |
\$\endgroup\$
  • \$\begingroup\$ Thanks! There is one thing which is not clear to me: in the calculator you link, they ask me to provide the Pollution Degree. Reading the definition is not very helpful, since they all reference on-earth conditions. Should I just assume that space = clean room/air sealed environment? (and thus, Pollution Degree = 1) \$\endgroup\$ – Cesco Aug 21 '19 at 14:32
  • \$\begingroup\$ @Cesco If the unit is totally sealed, sealed with a pressure release valve, or resides in a vacuum I would assume very little pollution. Also, if you conformal coat the board that could provide a barrier between any dust/particles and the traces themselves. \$\endgroup\$ – user4574 Aug 22 '19 at 13:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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