Single Cell Li-ion to 3.3V

[kissste]

Hi,

I'm looking for a single cell li-ion (3.0-4.2v) to 3.3v step-down/step-up or just LDO tracking down to 3.0V and shutdown.

peak @250mA, for max 20 seconds, then sleep for minute

Thank you for any suggestions

something like - ucc3954 - but, it's obsolete
but does not even have to be complicate, simply LDO to 3.3v when above 3.3v and then track down to 3.0v, and shut down there

[kiran_shrestha]

Here I have filtered for you the list of LDOs, your option to choose with shutdown or no shutdown , and use voltage divider for proper shutdown level.

http://www.digikey.com/products/en/integrated-circuits-ics/pmic-voltage-regulators-linear/699?k=ldo&k=&pkeyword=ldo&pv129=76&FV=fff40027%2Cfff80182%2C10a40002%2C1f140000%2Cffe002bb%2C7ec0044%2C7ec0045%2C7ec0047%2C7ec004b&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=500