5 V, 0,5 A Power supply design

[tpetar]

The tranformer design that you gave was helpful thanks but how to calculate the values of the capacitors that you used.

You can use datasheet design provided by manufacturer. Add 100nF on end of 7805 output to make ripple lower.

You dont need to calc nothing in this design, but if you want 1000uF per 1A for filtering AC riple before regulator (after bridge rectifier).

Best is to have oscilloscope to see shape of output current. :wink:

 

[jeffrey samuel]

i have a question how does the wiseman know all the points shared by thread starter

 

[tpetar]

i have a question how does the wiseman know all the points shared by thread starter

Yes my friend, I see that often lately. Maybe one user two accounts who knows.

 

[jeffrey samuel]

is it not against the rules of the forum

any design is said above can be used but can any one tell me when a transformer less ckt can be used instead of transformer ckt in conversion of AC to DC

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is it not against the rules of the forum

any design is said above can be used but can any one tell me when a transformer less ckt can be used instead of transformer ckt in conversion of AC to DC

 

[Tahmid]

any design is said above can be used but can any one tell me when a transformer less ckt can be used instead of transformer ckt in conversion of AC to DC

Transformerless circuits are usually used when current requirement is very low and isolation is not necessary, eg. LED lighting. Maximum "safe" current level could be about 50mA to 100mA.

For higher current and less bulky circuit (compared to 50Hz transformer-based circuits), SMPS may be used. Here, a transformer is used, providing isolation. And high output current may be obtained.

Hope this helps.
Tahmid.

 

[jeffrey samuel]

thanks pal had this question for a long time

 

[tpetar]

is it not against the rules of the forum

any design is said above can be used but can any one tell me when a transformer less ckt can be used instead of transformer ckt in conversion of AC to DC

Hi Jeffrey and others,

Additional to Tahmid :

Transformeless is used in situations when you want to have lower weight of device or have small budget for project or You have small space for device (there is no space for transformer).


Lets say You need LED on 220V, what will You use : Design with transformer or transformeless ?

Transformerless LED on 220V

Transformerless LED array on 220V