I have bought a low noise regulator as replacement for a standard LM317. I am not sure about the wiring and would really appreciate som help.
This is what I have measured on the LM317 that is assembled today:
Input - pin 1: 12v
Output - pin 2: 5v
Adjust - pin 3: 3.8v
As far as I understand I have to make some adjustment to the new regulator to feed the power correctly??
Very Low Noise 40?V Adjustable Voltage Regulator Board 3 Amp | eBay
This is what I have measured on the LM317 that is assembled today:
Input - pin 1: 12v
Output - pin 2: 5v
Adjust - pin 3: 3.8v
As far as I understand I have to make some adjustment to the new regulator to feed the power correctly??
Very Low Noise 40?V Adjustable Voltage Regulator Board 3 Amp | eBay
You need to adjust the new regulator to 5 volts before fitting. The PDF shows a 10 K preset to set the voltage.
Fitting should be straightforward. I would remove the LM317 and the components that set the voltage on your existing reg.
You must confirm the voltage is correct before fitting. Get it wrong and it could well damage whatever you are powering.
Fitting should be straightforward. I would remove the LM317 and the components that set the voltage on your existing reg.
You must confirm the voltage is correct before fitting. Get it wrong and it could well damage whatever you are powering.
The new regulator is adjusted to 5V but I am not sure about the fitting when I look at the wiring diagram for the new regulator. The 317 is not grounded and how am I to get 3.8V from pin 3 of the the new regulator? Input and output is easy but nr.3?
You don't need the 3.8 volts. Thats a voltage generated by the original LM317 on its adjust pin. Look at the data sheet for the LM317 to help make it clearer,
http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS009063.PDF
I would call pin 1 the adjust pin and 3 the input. SO CHECK THAT DATA SHEET FIRST
Look at figure 1 and the pin outs on page 12
All good ?
1. You take the LM317 out.
2. I would then remove the voltage setting components that go to pin 1 on the LM317. Probably two resistors as in the data sheet, one going to the 5 volt line and one to ground.
3. Connect your new reg. Make sure the grounds are correct and that they really do go to a ground NEAR THE OLD REG. That's important. Look for small decoupling caps near the LM317 and use those points as ground.
4. Connect the new regulator input to pin and that the input goes to pin 3 (where you measured 12 volts) of the LM317 pads.
5. Connect the output of the new reg to pin 2 of the LM317 pads.
Job done
http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS009063.PDF
I would call pin 1 the adjust pin and 3 the input. SO CHECK THAT DATA SHEET FIRST
Look at figure 1 and the pin outs on page 12
All good ?
1. You take the LM317 out.
2. I would then remove the voltage setting components that go to pin 1 on the LM317. Probably two resistors as in the data sheet, one going to the 5 volt line and one to ground.
3. Connect your new reg. Make sure the grounds are correct and that they really do go to a ground NEAR THE OLD REG. That's important. Look for small decoupling caps near the LM317 and use those points as ground.
4. Connect the new regulator input to pin and that the input goes to pin 3 (where you measured 12 volts) of the LM317 pads.
5. Connect the output of the new reg to pin 2 of the LM317 pads.
Job done
You don't need the 3.8 volts. Thats a voltage generated by the original LM317 on its adjust pin. Look at the data sheet for the LM317 to help make it clearer,
http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS009063.PDF
I would call pin 1 the adjust pin and 3 the input. SO CHECK THAT DATA SHEET FIRST
Look at figure 1 and the pin outs on page 12
All good ?
1. You take the LM317 out.
2. I would then remove the voltage setting components that go to pin 1 on the LM317. Probably two resistors as in the data sheet, one going to the 5 volt line and one to ground.
3. Connect your new reg. Make sure the grounds are correct and that they really do go to a ground NEAR THE OLD REG. That's important. Look for small decoupling caps near the LM317 and use those points as ground.
4. Connect the new regulator input to pin and that the input goes to pin 3 (where you measured 12 volts) of the LM317 pads.
5. Connect the output of the new reg to pin 2 of the LM317 pads.
Job done
Just great
Well explained and understandable for a "no tech" like me. Thank you very much for support. Guys like you make DIY for ever so fun!- Status
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