Light dimmer

Uh, why not do what GM has always done? A relay and a diode...

I just feed a relay to the head lights, They last just as long. Works great, people still cut me off.

Cheers

Nedavno Martin Riddle napisa:

I already did that, I just wanted to use high beams at, say 50-60% as drl's as BMW factory solution for E36.

The MOSFET needs to have several volts between its gate and source to be turned on. If you put the head light in the source leg you need to run the 555 on a higher voltage or the MOSFET won't see the needed gate drive and there will be a large loss in it.

You have several options.

(1) Use a P-channel MOSFET. The source would go to the +12V and the drain to the light.

(2) Use a PNP transistor for each head light. The drain of the MOSFET would drive the base connections through a hefty resistor.

(3) See that the law allows you to drive the car as it was made and leave it alone.

ANY design with the notation "555" in it, by definition, sucks.

Use a PIC!

You sound like Slowman.

Ick.

Don Lancaster is another one who's living in his own past... much like Billy Bob Slobman :-) ...Jim Thompson

Nedavno MooseFET napisa:

Like this?

I now have low beams as drl's (switched on with ignition via unloader relay). But I would like to use high beams (BMW factory solution for E36).

What do the regulations dictate?

Would it suffice to use relays to series the two high beams? ...Jim Thompson

cd4538 works well.

Oh and I checked the local library for those Modern Electronics. No dice, they have everything else tho.

Cheers

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

I think GM use to use that technique on their trucks, now its just one light.

Cheers

You'd need a p-channel fet.

A 60 watt, 12-volt lamp may pull 50 amps at turnon, enough to fry the fet. I'd use a big power resistor and no electronics.

BUZ60 is the wrong sort of fet anyhow. It's rated at 400 volts, 1 ohm Ron.

John

You have the MOSFET sources wired to the bulbs. This is not going to work.

#291606 **

This should work

Nedavno Jim Thompson napisa:

Probably, but both light bulbs are grounded at the headlight, so I think that I can not do what you are suggesting.

What requirements are dictated by the law? Brightness? ...Jim Thompson

-- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

Nedavno MooseFET napisa:

What about this:

-- ___ ____ /__/ / \ ** Registrovani korisnik Linuksa #291606 ** / / \/ /\ \ ** Registered Linux user #291606 ** /__/\____/--\__\ **

Cool. 96 amps, if you don't use the leads. IR has even higher current fets, if you don't use the leads.

But 300 watts in a DPAK?

John

Nedavno Muzaffer Kal napisa:

Not available here, not economical to order from digikey.com