I am trying to build a flyback converter that has
a single power MOSFET which is being driven by a TL494 chip (PWM)
Now I have a problem connecting most of the pins of
the PWM.I have had a look at the TI site but the problem
is they just don't explain how they come with those
specific resistor/capacitor values around the PWM pins
To set the oscillator frequency is straightforward
but the rest of the pins are just quite difficult to connect

My flyback is provided with; 28 Volts D.C. at the input
=:it must have short circuit protection
=:it must have current & voltage control
loop(preferably UNisolated)
=:the output of the transformer MUST be
5Volts DC at 1amp
=:the flyback uses a transformer with a tertiary
winding (clamp)

I will really be greatful if I could be helped.

I can send picture of the flyback if necessary but it
resembles the one appearing on the site
"personal.u-net.com/~hills2/electron/smps.htm" on pg 14
Though mine one has no input rectifier since dc is going in

My sincere thanks

Hi Joeseph, National Semiconductor has a range of single chip switching regulators that should do what you're after simply. You should be able to get a computer disk from National with all the design programs on it. Check with NS. Don Black.

: I am trying to build a flyback converter that has
: a single power MOSFET which is being driven by a TL494 chip (PWM)
: Now I have a problem connecting most of the pins of
: the PWM.I have had a look at the TI site but the problem
: is they just don't explain how they come with those
: specific resistor/capacitor values around the PWM pins
: To set the oscillator frequency is straightforward
: but the rest of the pins are just quite difficult to connect

: My flyback is provided with; 28 Volts D.C. at the input
: =:it must have short circuit protection
: =:it must have current & voltage control
: loop(preferably UNisolated)
: =:the output of the transformer MUST be
: 5Volts DC at 1amp
: =:the flyback uses a transformer with a tertiary
: winding (clamp)

: I will really be greatful if I could be helped.

:
: I can send picture of the flyback if necessary but it
: resembles the one appearing on the site
: "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: Though mine one has no input rectifier since dc is going in

: My sincere thanks

: Hi Joeseph, National Semiconductor has a range of single chip switching regulators that should do what you're after simply. You should be able to get a computer disk from National with all the design programs on it. Check with NS. Don Black.

: : I am trying to build a flyback converter that has
: : a single power MOSFET which is being driven by a TL494 chip (PWM)
: : Now I have a problem connecting most of the pins of
: : the PWM.I have had a look at the TI site but the problem
: : is they just don't explain how they come with those
: : specific resistor/capacitor values around the PWM pins
: : To set the oscillator frequency is straightforward
: : but the rest of the pins are just quite difficult to connect

: : My flyback is provided with; 28 Volts D.C. at the input
: : =:it must have short circuit protection
: : =:it must have current & voltage control
: : loop(preferably UNisolated)
: : =:the output of the transformer MUST be
: : 5Volts DC at 1amp
: : =:the flyback uses a transformer with a tertiary
: : winding (clamp)

: : I will really be greatful if I could be helped.

: :
: : I can send picture of the flyback if necessary but it
: : resembles the one appearing on the site
: : "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: : Though mine one has no input rectifier since dc is going in

: : My sincere thanks

: : Hi Joeseph, National Semiconductor has a range of single chip switching regulators that should do what you're after simply. You should be able to get a computer disk from National with all the design programs on it. Check with NS. Don Black.

: : : I am trying to build a flyback converter that has
: : : a single power MOSFET which is being driven by a TL494 chip (PWM)
: : : Now I have a problem connecting most of the pins of
: : : the PWM.I have had a look at the TI site but the problem
: : : is they just don't explain how they come with those
: : : specific resistor/capacitor values around the PWM pins
: : : To set the oscillator frequency is straightforward
: : : but the rest of the pins are just quite difficult to connect

: : : My flyback is provided with; 28 Volts D.C. at the input
: : : =:it must have short circuit protection
: : : =:it must have current & voltage control
: : : loop(preferably UNisolated)
: : : =:the output of the transformer MUST be
: : : 5Volts DC at 1amp
: : : =:the flyback uses a transformer with a tertiary
: : : winding (clamp)

: : : I will really be greatful if I could be helped.

: : :
: : : I can send picture of the flyback if necessary but it
: : : resembles the one appearing on the site
: : : "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: : : Though mine one has no input rectifier since dc is going in

: : : My sincere thanks

: Hi Joeseph, National Semiconductor has a range of single chip switching regulators that should do what you're after simply. You should be able to get a computer disk from National with all the design programs on it. Check with NS. Don Black.

: : I am trying to build a flyback converter that has
: : a single power MOSFET which is being driven by a TL494 chip (PWM)
: : Now I have a problem connecting most of the pins of
: : the PWM.I have had a look at the TI site but the problem
: : is they just don't explain how they come with those
: : specific resistor/capacitor values around the PWM pins
: : To set the oscillator frequency is straightforward
: : but the rest of the pins are just quite difficult to connect

: : My flyback is provided with; 28 Volts D.C. at the input
: : =:it must have short circuit protection
: : =:it must have current & voltage control
: : loop(preferably UNisolated)
: : =:the output of the transformer MUST be
: : 5Volts DC at 1amp
: : =:the flyback uses a transformer with a tertiary
: : winding (clamp)

: : I will really be greatful if I could be helped.

: :
: : I can send picture of the flyback if necessary but it
: : resembles the one appearing on the site
: : "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: : Though mine one has no input rectifier since dc is going in

: : My sincere thanks

: Hi Joeseph, National Semiconductor has a range of single chip switching regulators that should do what you're after simply. You should be able to get a computer disk from National with all the design programs on it. Check with NS. Don Black.

: : I am trying to build a flyback converter that has
: : a single power MOSFET which is being driven by a TL494 chip (PWM)
: : Now I have a problem connecting most of the pins of
: : the PWM.I have had a look at the TI site but the problem
: : is they just don't explain how they come with those
: : specific resistor/capacitor values around the PWM pins
: : To set the oscillator frequency is straightforward
: : but the rest of the pins are just quite difficult to connect

: : My flyback is provided with; 28 Volts D.C. at the input
: : =:it must have short circuit protection
: : =:it must have current & voltage control
: : loop(preferably UNisolated)
: : =:the output of the transformer MUST be
: : 5Volts DC at 1amp
: : =:the flyback uses a transformer with a tertiary
: : winding (clamp)

: : I will really be greatful if I could be helped.

: :
: : I can send picture of the flyback if necessary but it
: : resembles the one appearing on the site
: : "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: : Though mine one has no input rectifier since dc is going in

: : My sincere thanks

I am trying to design a +12V to -5V Switching Converter
and it is a 12W continous non-Isolated Flyback Converter.

Spec. .5A min 2.4max

: I am trying to build a flyback converter that has
: a single power MOSFET which is being driven by a TL494 chip (PWM)
: Now I have a problem connecting most of the pins of
: the PWM.I have had a look at the TI site but the problem
: is they just don't explain how they come with those
: specific resistor/capacitor values around the PWM pins
: To set the oscillator frequency is straightforward
: but the rest of the pins are just quite difficult to connect

: My flyback is provided with; 28 Volts D.C. at the input
: =:it must have short circuit protection
: =:it must have current & voltage control
: loop(preferably UNisolated)
: =:the output of the transformer MUST be
: 5Volts DC at 1amp
: =:the flyback uses a transformer with a tertiary
: winding (clamp)

: I will really be greatful if I could be helped.

:
: I can send picture of the flyback if necessary but it
: resembles the one appearing on the site
: "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: Though mine one has no input rectifier since dc is going in

: My sincere thanks

: : I am trying to build a flyback converter that has
: : a single power MOSFET which is being driven by a TL494 chip (PWM)
: : Now I have a problem connecting most of the pins of
: : the PWM.I have had a look at the TI site but the problem
: : is they just don't explain how they come with those
: : specific resistor/capacitor values around the PWM pins
: : To set the oscillator frequency is straightforward
: : but the rest of the pins are just quite difficult to connect

: : My flyback is provided with; 28 Volts D.C. at the input
: : =:it must have short circuit protection
: : =:it must have current & voltage control
: : loop(preferably UNisolated)
: : =:the output of the transformer MUST be
: : 5Volts DC at 1amp
: : =:the flyback uses a transformer with a tertiary
: : winding (clamp)

: : I will really be greatful if I could be helped.

: :
: : I can send picture of the flyback if necessary but it
: : resembles the one appearing on the site
: : "personal.u-net.com/~hills2/electron/smps.htm" on pg 14
: : Though mine one has no input rectifier since dc is going in

: : My sincere thanks

:
: I want to build a smps 1000watts output input voltage 220 volt ac
: Tell me what will the size of core and the number of mosfet. : I will really be greatful if I could be helped.

: My sincere thanks