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edit approved Jan 23, 2016 at 19:56
uint128_t
edit approved Jan 23, 2016 at 19:56
uint128_t
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Over volt protection is a common and accepted practice  .There There are many ways of doing this, but I wontwon't mention them all  .First Firstly, you can place a big Zener diode across the output that is arranged to conduct heavily before the max voltvoltage rating of the chips are exceeded  .If If the zener eventualyZener eventually fails short circuit the chips are safe  .Secondly

Secondly, you can place a big SCR across the output that is arranged to fire when an overvoltovervoltage occurs  .This This is a very old scheme that dates back to big linear regulators and mainframe computers.It is effective .Third

Thirdly, what I do is place a cheap, low RDs onRds(on) N chan mosfet-chan MOSFET in series with the output of the buck converter  .I I drive the gate of the fetMOSFET with DC that comes from the convertorconverter switching waveform  .I I use a simple diode pump to do this  .If If the main buck converter fetFET fails short circuit which is the most likely failure mode the diode pump stops and the power is cut off  .There

There are also converter topologies that dontdon't give an overvoltovervoltage when the switch fails short circuit but they are not as simple and as efficient as the buck converter.

Over volt protection is common and accepted practice  .There are many ways of doing this I wont mention them all  .First you can place a big Zener across the output that is arranged to conduct heavily before the max volt rating of the chips are exceeded  .If the zener eventualy fails short circuit the chips are safe  .Secondly you can place a big SCR across the output that is arranged to fire when an overvolt occurs  .This is a very old scheme that dates back to big linear regulators and mainframe computers.It is effective .Third what I do is place a cheap low RDs on N chan mosfet in series with the output of the buck converter  .I drive the gate of the fet with DC that comes from the convertor switching waveform  .I use a simple diode pump to do this  .If the main buck converter fet fails short circuit which is the most likely failure mode the diode pump stops and the power is cut off  .There are converter topologies that dont give an overvolt when the switch fails short circuit but they are not as simple and as efficient as the buck .

Over volt protection is a common and accepted practice. There are many ways of doing this, but I won't mention them all. Firstly, you can place a big Zener diode across the output that is arranged to conduct heavily before the max voltage rating of the chips are exceeded. If the Zener eventually fails short circuit the chips are safe.

Secondly, you can place a big SCR across the output that is arranged to fire when an overvoltage occurs. This is a very old scheme that dates back to big linear regulators and mainframe computers.

Thirdly, what I do is place a cheap, low Rds(on) N-chan MOSFET in series with the output of the buck converter. I drive the gate of the MOSFET with DC that comes from the converter switching waveform. I use a simple diode pump to do this. If the main buck converter FET fails short circuit which is the most likely failure mode the diode pump stops and the power is cut off.

There are also converter topologies that don't give an overvoltage when the switch fails short circuit but they are not as simple and as efficient as the buck converter.

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Autistic
Autistic
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Over volt protection is common and accepted practice .There are many ways of doing this I wont mention them all .First you can place a big Zener across the output that is arranged to conduct heavily before the max volt rating of the chips are exceeded .If the zener eventualy fails short circuit the chips are safe .Secondly you can place a big SCR across the output that is arranged to fire when an overvolt occurs .This is a very old scheme that dates back to big linear regulators and mainframe computers.It is effective .Third what I do is place a cheap low RDs on N chan mosfet in series with the output of the buck converter .I drive the gate of the fet with DC that comes from the convertor switching waveform .I use a simple diode pump to do this .If the main buck converter fet fails short circuit which is the most likely failure mode the diode pump stops and the power is cut off .There are converter topologies that dont give an overvolt when the switch fails short circuit but they are not as simple and as efficient as the buck .