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View Full Version : Battery Powered Need Help!



scottl
- 28th March 2006, 14:57
I do not know how I get myself into these positions but here it is!

I am working on a Bluetooth sensor that must be powered from a 3.6V Lithium-Ion battery. Battery life can be a 4, 5 hours, I am going to add a charging circuit. The Bluetooth transceiver must run from max 3.4v to min 3.2v 120mA TX and 50mA receive. I have an AD595 that requires 5v. I am getting confused to which regulator, charge pump etc.. will do the job. I am looking at using an LTC1517-5 20mA for 5v to a PIC12F675 and the AD595.

Can anyone suggest a regulator or how I can ensure 3.3V to my Bluetooth circuit?

Thanks for the help,

Scott

sougata
- 29th March 2006, 10:52
Hi,

A general purpose silicon diode has a forward voltage drop of around 0.6volts which does vary with temperature, but nothing of caution. If you simply put three of these diodes in series with your 5volts supply you loose 1.8 volts. That is 3.2 volts. Normal diode losses and pretty stable.

Hope this helps