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[SOLVED] power supply -48 vdc
- Thread starter foxbrain
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rfredel
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Hello foxbrain,
here you have a schematic of power supply.
If you need an other line voltage, only take a transformer with your line voltage
Regards
Rainer
here you have a schematic of power supply.
If you need an other line voltage, only take a transformer with your line voltage
Regards
Rainer
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AG1110... If this IC is to be used in a telephone system, then the incoming telephone line is at -48V (more or less) relative to earth ground.
However if it is not present, then you can obtain it by chopping a DC supply into pulses, and feed that to a voltage multiplier.
Or use a boost converter. Etc.
However if it is not present, then you can obtain it by chopping a DC supply into pulses, and feed that to a voltage multiplier.
Or use a boost converter. Etc.
foxbrain
Full Member level 2
what do u mean by it ? and how can i make it?
the voltage from the phone line changes when it rings and when someone is talking..... isn't that right?
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The phone line has -48 V on it when there is no activity. It could be as much as -60V amplitude (or greater).
When the phone is ringing, I believe it has 90 VAC coming into the phone.
When the phone is off the hook, you will measure much lower amplitude than -48V.
This means you cannot power the IC from the phone line during those times.
So it's likely you will need to obtain (or construct) a power supply which draws from house current, as Rfredel recommends (post #2).
The methods I spoke of are difficult.
rfredel
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Hello foxbrain,
in this schmatic you see the Z-diode in the ground connection of 7924. So you set the regulator ground to -24V. In addition to the output will be -48V.
Its a circuit to make the fix voltage higher then without Z-diode.
Regards
Rainer
in this schmatic you see the Z-diode in the ground connection of 7924. So you set the regulator ground to -24V. In addition to the output will be -48V.
Its a circuit to make the fix voltage higher then without Z-diode.
Regards
Rainer
Aalia Nebhan
Newbie level 1
Nicely presented information in this forum, I prefer to read this kind of stuff.
The quality of content is fine and the conclusion is good.
Thanks for the post.
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garden outdoor lighting
The quality of content is fine and the conclusion is good.
Thanks for the post.
..........................................................
garden outdoor lighting
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