On 20/01/2011 19:25, Vitaliy wrote:
> Hi List,
>
> I'm looking for a 5V out switching regulator with a quiescent current of<=
1
> mA, capable of supplying 300 mA. It should operate across a wide voltage
> range, from 8V up to 32V, and be able to survive 36V. It must also be sma=
ll,
> and cheap.
>
> We did our prototyping with Seiko's S-8520:
>
> http://datasheet.sii-ic.com/en/switching_regulator/S8520_8521_E.pdf
>
> It's a nice little device, but it has two big flaws: it can only go up to
> 16V, and it has a three month lead time.
>
> I understand some of you chuckled in disbelief, or even rolled on the flo=
or
> laughing after reading the first paragraph (you know who you are), so let=
 me
> relax the requirements a little bit:
>
> I would be OK if I could find a regulator that accepts 8-18V on the input=
,
> and survives 24V for 10 minutes, as long as it meets the quiescent curren=
t
> spec. I'm even OK with adding cheap external components to shut off the
> regulator if the voltage exceeds 16V.
>
> Thank you in advance for your help.
>
> Vitaliy
>
8V to 36V is doable. Lets you use really flat 12V car battery or madly=20
excited 24V Truck electrics.

series transistor or linear regulator to power low power < 1mA SMPSU IC=20
that uses one external FET switch.
max of about 30mW in your series linear supply for SMPU IC and the=20
external fet can easily do 0 to 500mA at even 60V in

If you wanted it in one part with only a couple of caps and one coil I'd=20
think that's harder.
--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.