Ultra Low Quiescent Current Adjustible Regulator - Page 1
Forum section: electronics / projects

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 11:43:57 am
content: I'm looking for a very low quiescent current switching regulator that can supply at least 1.5A. All the chips I've found so far are fixed voltage, but I need 3.7V.What I want to do is run a single cell Li-Ion powered device from a 2 cell Li-Ion battery. This is a one-off, personal project.Can anyone suggest a suitable chip?

author: eevblogfan
author_rank: Frequent Contributor
timestamp: September 26, 2013, 11:55:57 am
content: HeyI wonder why didn't you published the average current over time ( if you can estimate some .. )and the battery pack's capacity , is it CC, CR, CP load ?What is the Highest PARAD figure the app is going to tolerate ?is size is big issue ?how long should it run ?Thank you

author: Bored@Work
author_rank: Super Contributor
timestamp: September 26, 2013, 11:56:29 am
content: LT3975?

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 12:07:38 pm
content: Quote from: Bored@Work on September 26, 2013, 11:56:29 amThat looks promising. It's disappointing that the 2 companies I mainly order from (E14 and Mouser) don't carry it.Thanks.

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 12:14:20 pm
content: Quote from: eevblogfan on September 26, 2013, 11:55:57 amIn use, between 1 and 1.5 A. In standby, a couple of uA.QuoteWhat?QuoteFor the regulator? No not really. For the battery, I already have the batteries.QuoteThat is already taken care of. All I'm interested in is as little power being consumed as possible in standby mode.

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 12:38:06 pm
content: Can anyone suggest an appropriate inductor and diode for the LT3975? Preferably something available from Digikey. I have plenty of PCB space.I'll put in the time to research it myself if someone doesn't know off the top of their head.

author: eevblogfan
author_rank: Frequent Contributor
timestamp: September 26, 2013, 06:06:07 pm
content: HeySorry for talking not clear , I meant Periodic and random deviations (PARD) in the output (ripple and noise) ( copied directly from HP6632B or pretty any other HP/Agilent's manuals ... )What I think I should have asked is the highest ripple and peak to Peak RMS you'r application is going to tolerate ,Quote from: mojo-chan on September 26, 2013, 03:52:34 pm1+ for that

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 08:18:40 pm
content: Quote from: mojo-chan on September 26, 2013, 03:52:34 pmThat was my first idea. The problem is that the only way I can know the device is turned on is by detecting current draw. I doubt I'd be able to get a switching reg to switch on quick enough.

author: Mike Warren
author_rank: Unknown
timestamp: September 26, 2013, 08:21:27 pm
content: Quote from: eevblogfan on September 26, 2013, 06:06:07 pmNone of that is critical. Any standard switching regulator will be good enough.

author: Mike Warren
author_rank: Unknown
timestamp: September 27, 2013, 09:56:55 pm
content: Quote from: mojo-chan on September 27, 2013, 03:27:29 pmThe device is a video camera and I want to make an add-on device that adds some extra functionality. One of the things it will do is give the ability to use much larger batteries, but these are only available in 2 cell.I can't remotely turn on the video camera, so I want to detect when the camera is turned on and automatically turn on my circuit.But I'm going to look at the feasibility of adding a socket to the camera so I can get at the power switch as this will simplify the project.