WTB: Low-power 555 (551, 7555, similar)

[charliebruce]

Hi all,
I was wondering if anyone here has a low-power, pin-compatible version of the 555 timer spare. Ideally it should operate down to 1.5v or even as low as 1v if possible. If anyone has these to hand, it would save me the time and per-order costs of buying from one of the standard suppliers. I don't mind if it's SMT or through-hole. I'd be happy to pay about $5 + shipping if necessary. Feel free to post or PM.

Thanks
Charlie

 

[phoenix77]

Hey Charlie, where would you find something like that ? I have about 20 older model (10 to 12 year old) computer towers from a school that was up-grading their systems. If what you need is possibly in one of them, tell me what & where to look for, & if I have it, YOU can HAVE it, FREEBIE !!!!! rob
PS, can ya tell I have no idea what it is you're wanting ? I'm not too computer savvy. I'm lucky I know how to turn mine on. HA HA HA !!!!!!!!!!!

 

[charliebruce]

Hi,
The 555 timer is an 8-pin chip that's used for timing and creating pulses in circuits. To be honest, I don't know if they would be found in old PCs, but if there were one, I don't think it would be able to run at a low enough voltage. The reason I asked here is that they're a pretty common chip, and so perhaps a few of the electronic engineers might have one spare, hopefully in a low-voltage form.

Thanks for the thought,
Charlie

 

[Hemlock_Mike]

Wow has time passed me -- I am not aware of a 555 in any configuration which runs at 1 to 1.5 volts. I'd like a couple too !

HMike

 

[phoenix77]

Oh, I see now. Well, just tryin' to help out a friend, sorry it was for naught. rob

 

[charliebruce]

The TLC551 chip is pin-compatible, and runs right down to 1v. The project I'd like it for is a "drawdio" - basically uses the resistance of graphite or a human body, combined with a capacitor, to create a sound wave which is then amplified. The best one I've seen so far is at Drawdio! which is where I heard about the low-voltage types of 555.

 

[Hemlock_Mike]

I'll be GTH !! You are right. I never knew that there was a 555 which would run at only 1 volt. I learned something today !!

Thanks -- HMike

I found them on P975 of my digikey catalog. SOIC and DIP.
Check your PM.

 

[Hemlock_Mike]

These might be nice for driving MosFets with low voltage in PWM circuits.

HMike

 

[brtaman]

But the 1v out will barely make the gate budge. :tinfoil:

Nice find, charliebruce, usefull bit of kit, TI all the way!

BTW, they will be more than happy to send you 5 samples of the TLC551, if it is on their sampling list. They ship with FedEx so it will be at your house in a day or two.


Best Regards,
brtaman

 

[Hemlock_Mike]

Charlie ---

The chips are on the way to me. Check your PM.

HMike

BRT -- These will run above 1 volt which gives me some lattatude for drive.