Actions
Forum Thread Details
  • State Not Answered
  • Replies 10 replies
  • Subscribers 302 subscribers
  • Views 2433 views
  • Users 0 members are here
Related
See a helpful answer?

Be sure to click 'more' and select 'suggest as answer'!

If you're the thread creator, be sure to click 'more' then 'Verify as Answer'!

Reverse protection of Multicomp pro DC/DC converters MP-K78xx?

DavidOB

Hi,

I'm unable to find rating and description of MP-K78xx DC/DC converters in respect to reverse current/voltage protection. I have some questions:

1. What happens if another voltage source is connected to the output if this converter is not powered and used with typical application circuitry with input/output 10/22uF ceramics capacitors?

2. Same question as 1. but what if the converter is powered?

3. Same question as 1. but what if the converter input is shorted to ground?

3. What would happen if that another source voltage is higher than the converter nominal output? E.g. MP-K7803-500R3 is used for a battery powered device and USB + is connected to the output power rail while connected with a PC. If USB cable is connected, its 5V would then go into this 3.3V K7803 output.

Parents
  • 0

    Thanks for the responses. Shabaz, I have read that sequence about "hot swap and parallel" several times but did not realize that in fact suggests the answers!

    Seems the answer to all questions is "it would probably fail" :-) and to prevent it, a Schottky (or a P-FET for lower drop) in series with the output should do the trick. A diode across the converter from Vout to Vin is not a good option as that would make a short from the external source to ground via this diode in case of my first Q3 situation (my bad for two threes, sorry).

Reply
  • 0

    Thanks for the responses. Shabaz, I have read that sequence about "hot swap and parallel" several times but did not realize that in fact suggests the answers!

    Seems the answer to all questions is "it would probably fail" :-) and to prevent it, a Schottky (or a P-FET for lower drop) in series with the output should do the trick. A diode across the converter from Vout to Vin is not a good option as that would make a short from the external source to ground via this diode in case of my first Q3 situation (my bad for two threes, sorry).

Children
No Data