Help: Design a transformer from Car Battery to 4.5v level? - Electronic Circuits Projects Diagrams Free

TheMatrix65 · 15th August 2002, 10:16 PM

I have a battery-operated Trafficmaster which tells me of any traffic jams 12 miles ahead of me, etc. This device uses 3 x AAA batteries which I usually replace approximately 1-2 months, depending on how often I drive my car. Now, I would like to wire it "permanently" to a car battery by way of a transformer to downgrade 12v into 4.5v with the equivalent amperage as those of 3 x AAA batteries. Could anyone design such a small transformer that would do the job so it would save me buying batteries all the time. The design (pcb and components) would need to be small enough, say 6cm by 3cm by 6cm, overall? (Those are approximations, as I am installing it near the courtesy light compartment (it has a permanent 12v feed as well as ground feed)).

Much appreciated.

rmyers2051 · 16th August 2002, 01:40 AM

A simple voltage regulator such as Radio Shack #276-1770, which is in reality, a "7805 regulator" will do nicely. Simple point to point wiring and potted in epoxy using a matchbox would be a snap!

charles hafer · 2nd September 2002, 09:06 AM

:lol: could use a 4.7 volt zener and one resistor too. i guess the resistor value to be approximately 510 ohms.

bogdanfirst · 14th December 2002, 04:03 PM

u can use a 7805 or 78L05 depending of the power it consumes...witch generates 5V then conect a diode after it maybe a Ge one to have a dorop of voltage of about 0.4V(Ge) or 0.6 V(Si) thats if 5 volte is 2 much...
:roll:

15th August 2002, 10:16 PM	(permalink)
TheMatrix65 New Member	Help: Design a transformer from Car Battery to 4.5v level? I have a battery-operated Trafficmaster which tells me of any traffic jams 12 miles ahead of me, etc. This device uses 3 x AAA batteries which I usually replace approximately 1-2 months, depending on how often I drive my car. Now, I would like to wire it "permanently" to a car battery by way of a transformer to downgrade 12v into 4.5v with the equivalent amperage as those of 3 x AAA batteries. Could anyone design such a small transformer that would do the job so it would save me buying batteries all the time. The design (pcb and components) would need to be small enough, say 6cm by 3cm by 6cm, overall? (Those are approximations, as I am installing it near the courtesy light compartment (it has a permanent 12v feed as well as ground feed)). Much appreciated.

2nd September 2002, 09:06 AM	(permalink)
charles hafer New Member	4.5 volt transformer :lol: could use a 4.7 volt zener and one resistor too. i guess the resistor value to be approximately 510 ohms. __________________ charles hafer

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Latest
Circuit Design: Transformer (or Inverter?)	jrod5000	Electronic Projects Design/Ideas/Reviews	5	2nd November 2007 04:51 PM
primitive early design for battery charging	faomari	General Electronics Chat	3	2nd May 2006 03:22 PM
Transformer + battery = School Thrills	windozeuser	General Electronics Chat	3	14th December 2005 09:27 PM
Suitable battery type for design with LCD	janetsmith2000@yahoo.com	Electronic Projects Design/Ideas/Reviews	9	18th November 2005 05:04 AM
12 volt battery level measurement	Nesta	Electronic Projects Design/Ideas/Reviews	1	5th May 2004 03:50 PM

16th August 2002, 01:40 AM	(permalink)
rmyers2051 New Member	A simple voltage regulator such as Radio Shack #276-1770, which is in reality, a "7805 regulator" will do nicely. Simple point to point wiring and potted in epoxy using a matchbox would be a snap!

14th December 2002, 04:03 PM	(permalink)
bogdanfirst Experienced Member	u can use a 7805 or 78L05 depending of the power it consumes...witch generates 5V then conect a diode after it maybe a Ge one to have a dorop of voltage of about 0.4V(Ge) or 0.6 V(Si) thats if 5 volte is 2 much... :roll: