Power Supply 12v | Electronic Project Circuits

Posts Tagged ‘power supply 12v’

Easy Power supply for cassette player

This circuit that you see, It is an one style of an easy simple power supply, for a recorder or a cassette player in the car which used voltage 12V.It is only using the current abount 100mA.
When it occured over load current at output.it will not damaged with circuit.(have only current 2Amp) While it can to used the voltage about 6Volt at 800mA max.
The resistance of R1 serves to limit the short circuit current at about 2 amps.And reduce the power consumption of the series regulator transistor Q1.(which acts as the emitter follower circuit with a base voltage from R2, D1).
Here is the diode resistance should be 1 watt or more.
This circuit can be assembled into a small metal box, compact, easily. Using the heater box as cooling plate to transistors Q1 with built-in.
Designed by Mr. Enrich Reading Ford. Palmerston North City Seal Post Teen & Air UK.

Be the first to comment - What do you think? Posted by admin - March 25, 2011 at 6:52 pm

Categories: Power supply Tags: easy power supply, power supply 12v

Dual Power Supply 24V and 12V unregulator

There are two power supplies: one version for the amplifier and muting timer The power transformer secondary supplies about 18Vrms, so the V+ rail is about 24VDC, adequate also for hi-Z headphones. I donâ€™t like regulated power supply units for this kind of circuits, so a simple Pi filter is employed here, made by C2, C6 and R18. The PSRR of the audio circuit is about 30dB. With a 30-Ohm output load, Iâ€™ve measured about 350uV (1uV = 1*10-6 Volts!!); in spite of this, since the Grados are quite sensitive headphones, a little hum can be heard, only if the room noise floor is absolutely low and there is no signal applied at the input, of course.

Source:http://headwize.com/projects/
Thank you.

Be the first to comment - What do you think? Posted by admin - February 23, 2008 at 12:34 pm

Categories: Power supply Tags: 24v power supply, dual power supply, power supply 12v

12V Switching Car PSU by UC3843 + 74LS02

Here is circuit power supply switching 12V. For Car PSU use IC UC3843 and mosfet IRFZ44N.
It is nice circuit for electronics PC MP3 Player. System control by digital circuit IC 74LS02

The next version will be much like the V2, except for a few changes:

* Added a trimmer (R13) to the R8/R9 voltage divider so it’s easy to get the exact voltage wanted and you don’t have to change components to get another output voltage.
* Redone the PCB to fit the smaller low-imp caps that are about 2/3′s the size of the original electrolytes I got a hold of (at Elfa, the stock number is 67-183-32 ).
* Added a 5V regulator to allow the GPS receiver (or headunit) to stay on, even when the computer is off.
* Added a low power on/off switch to the PSU so it’s easy to control from a computer, the car should toggle the PSU on when the ignition is turned on, the computer should turn it off when pulling the off contact high while the car ignition wire is off. The +12v car ignition signal should also be conditioned so it’s suitable for a 5v input on a CPU and made available, the standby current is around 30mA, which I hope is low enough.

State Car [On] PC [Off] Output
Running 1 X On
Shutting down/off 0 0 No change, NOT OFF
Turn off (short) 0 1 Off

Read More Source:http://dion.swamp.dk/carpower.html
Thank you.