how design a electrnic switch for ac line(AC220V-50HZ-I<10A)

[[email protected]]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

 

[Fred Bloggs]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

Put two of them back-to-back in series.

 

[Pooh Bear]

Put two of them back-to-back in series.

Or put the FET inside a diode bridge.

Either way you're likely to want to use an optically coupled ( and isolated )
control signal.

Graham

 

[[email protected]]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

nowhere near enough info for a genuinely useful answer

 

[Noway2]

A Triac is often used to switch AC sources. They are basically two
back to back SCRs. Since AC has a zero crossing, when the gate drive
is removed, the devices can shut off as they will become reverse
biased.

Either way you go, just in case you hadn't thought of it, be sure to
include a snubber circuit.

 

[[email protected]]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

You are looking for a triac.

 

[martin griffith]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

if you dont need to use a mosfet try this page,
http://www.epanorama.net/circuits/semiconductor_relays.html#optoinput


martin

 

[Pooh Bear]

A Triac is often used to switch AC sources. They are basically two
back to back SCRs. Since AC has a zero crossing, when the gate drive
is removed, the devices can shut off as they will become reverse
biased.

Either way you go, just in case you hadn't thought of it, be sure to
include a snubber circuit.

Note that triacs continue conducting until the current falls to zero
though. It takes a polarity reversal for them to switch off. The mosfet
doesn't have that 'problem'.

Graham

 

[Rich Grise, but drunk]

I want to control AC line(AC220V) with "ON" or "OFF",I want use
mosfet to built it,
but power mosfet all have inside diode, it can conduct in
reverse direction,so it can not control ac source. how can I to design
this circuit for ac line switch?

If what you need to do is control an AC load by another signal, then
buy a solid-state relay.

If what you need to do is pass a test, then read the textbook again.

Good Luck!
Rich