Power Supply Unit
- Thread starter Angel
- Start date
Hello Angel.
If you just want a 5V supply for low power work then I wouldn't use any micro.
If you want some complicated power supply, variable voltage with adjustable current trip then maybe.
But as to whether it would simplify the circuit is very much down to your skill and abilities with electronics and code.
PICAXE can be used to drive an FET or an LED/LDR optocoupler to control a linear or s/mode regulator.
OR, for crude apps, it could PWM an FET to produce a simple buck s/mode design.
Or you could have pot control of a regulator and just use PICAXE/LCD to monitor and display.
But if you are expecting TTi LAB Bench PSU quality then don't bother.
Things have been done on this Forum before with FET control of a regulator.
But first, it would be a good idea if you told us:-
A) A desired specifcation. (Power etc. Do you want serial control etc. Knobs/buttons/LCD)
B) Your skill level in electronics and code writing.
C) Do you have any good test equipment.
D) Can you make PCBs?
People will help you and give some great advice but they will expect you to put in the effort.
For something half-decent it will be a difficult task.
I assume by the question that you are a novice, I hope this project isn't too difficult as a 'first' project.
Good luck.
If you just want a 5V supply for low power work then I wouldn't use any micro.
If you want some complicated power supply, variable voltage with adjustable current trip then maybe.
But as to whether it would simplify the circuit is very much down to your skill and abilities with electronics and code.
PICAXE can be used to drive an FET or an LED/LDR optocoupler to control a linear or s/mode regulator.
OR, for crude apps, it could PWM an FET to produce a simple buck s/mode design.
Or you could have pot control of a regulator and just use PICAXE/LCD to monitor and display.
But if you are expecting TTi LAB Bench PSU quality then don't bother.
Things have been done on this Forum before with FET control of a regulator.
But first, it would be a good idea if you told us:-
A) A desired specifcation. (Power etc. Do you want serial control etc. Knobs/buttons/LCD)
B) Your skill level in electronics and code writing.
C) Do you have any good test equipment.
D) Can you make PCBs?
People will help you and give some great advice but they will expect you to put in the effort.
For something half-decent it will be a difficult task.
I assume by the question that you are a novice, I hope this project isn't too difficult as a 'first' project.
Good luck.
Dippy,
Many thank for your early answer, I´m working on a new project, basically is a triplex power supply unit, where 2 are fixed ( 12v and 30v) and the last one should be adjustable(0 a 30 v), this PSU must be able of delivery 5 amps, of course I have to put a good instrumentation as well. I´m a new trainee in the PICAXE´s world, reading a lot but I can´t wait to know every thing before make some questions, on the other hand I can tell you, yes I can make a PCB´s.
Many thank for your early answer, I´m working on a new project, basically is a triplex power supply unit, where 2 are fixed ( 12v and 30v) and the last one should be adjustable(0 a 30 v), this PSU must be able of delivery 5 amps, of course I have to put a good instrumentation as well. I´m a new trainee in the PICAXE´s world, reading a lot but I can´t wait to know every thing before make some questions, on the other hand I can tell you, yes I can make a PCB´s.
Andrew Cowan
Senior Member
12V at 5A
You'll want a 7812. Look in the datasheet - it has techniques for increasing the maximum current from 2A (7812CV), to up to 15A. Beware it disipates excess voltage as heat - if you are just going to have one transformer that can do the 30V line as well, this is not practical (90W heat!). If you are going with one transformer, you'll want a switching regulator.
30V at 5A
Maybe an LM317T variable regulator - again with current increasing transistors.
0-30V adj
Maybe another LM317T? You could control it with a PICAXE using a FET (or digi pot) instead of the control resistor. Alternativly, you could make a SMPS using op amps and a PICAXE, but that's getting complex. PM me if you want some (very complex) plans.
I have to put a good instrumentation as well
PICAXE can do all the readouts, just use a shunt resistor for current, and a voltage divider for voltage.
Good luck!
You'll want a 7812. Look in the datasheet - it has techniques for increasing the maximum current from 2A (7812CV), to up to 15A. Beware it disipates excess voltage as heat - if you are just going to have one transformer that can do the 30V line as well, this is not practical (90W heat!). If you are going with one transformer, you'll want a switching regulator.
30V at 5A
Maybe an LM317T variable regulator - again with current increasing transistors.
0-30V adj
Maybe another LM317T? You could control it with a PICAXE using a FET (or digi pot) instead of the control resistor. Alternativly, you could make a SMPS using op amps and a PICAXE, but that's getting complex. PM me if you want some (very complex) plans.
I have to put a good instrumentation as well
PICAXE can do all the readouts, just use a shunt resistor for current, and a voltage divider for voltage.
Good luck!
BeanieBots
Moderator
In brief, very unlikely.Hello to all, I need to make a power supply unit, and I would like to know if Is possible to use any PICAXE, to simplify the circuit? Thank You a lot!
A PICAXE would be WAY too slow for dynamic control of a power supply.
It's OK for something like a battery charger or situations where the load does not vary a great deal and load/line regulation is not an issue.
eg.
http://www.picaxeforum.co.uk/showthread.php?t=10986
At the sort of power levels you are looking at, you should seriously consider a switcher type power supply. If you need a very clean supply with very fast response to load variations, then consider a switcher with a linear final stage output.
A PICAXE (or any micro) won't help you make a better supply but it could be used to help control the output demand values via push-buttons and/or to display what the output is set at and what the load current is.
EDIT:
Moved to active forum
Last edited: