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When AC is applied to a TV at what place of the circuit does it change to DC?

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rascabuche

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when ac is applied to a tv at what place of the circuit it changes to dc, and what measurement in voltages would one expect.
thanks.

ras
 

tamerakshar

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Re: ac-dc question


when ac is applied to a tv at what place of the circuit it changes to dc, and what measurement in voltages would one expect.
this part of the circuit is called the low voltage power supply,which supllies voltage to transistors & ICs; u can locate it by finding the large filter capacitor & low voltage silicon diodes.

 

tamerakshar

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Re: ac-dc question

what measurement in voltages would one expect.

after you power the tv switch on, the rectifier diodes rectify one half of the full cycle,then the large filter caps filter rippled dc voltage.
then voltage passes through the R-C filter network passing the signal to a large regulator IC.chk the attached photo.
any time ,
Regards,
TeE ThE EdE
 

tamerakshar

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Re: ac-dc question

what measurement in voltages would one expect

u you may measure approaximately a 140 dc voltage.
 

atlantis83

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Re: ac-dc question

It is a "flyback-converter" circuit that converts AC to DC in TVs.This circuit is called "switch mode power supply" which is different from linear regulators.In this circuit there are a transformer,capacitors,resistors,diodes and transistors.They convert 220V AC to 120V,40V,6V,5V...DC whatever you want.It depends on the ratio of N2/N1 of transformer.
 

tamerakshar

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Re: ac-dc question

It is a "flyback-converter" circuit that converts AC to DC in TVs.This circuit is called "switch mode power supply" which is different from linear regulators.In this circuit there are a transformer,capacitors,resistors,diodes and transistors.They convert 220V AC to 120V,40V,6V,5V...DC whatever you want.It depends on the ratio of N2/N1 of transformer.

chech back your information ;its not the fly back who converts AC to DC.
regards
TeE ThE EdE
 

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