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Supario
06-18-2005, 12:17 AM
Hi,

Are there any low drop out regulators readily available in India? I need a regulator with 5V output with around 500mA-1A current capacity that will run properly on a supply thats as low as 5.5V-6V. I looked for the MAX660 and LM2940 but they dont seem to be available here (Bangalore).

Thanks,
Supario

subot_robot
06-18-2005, 08:09 AM
Hi Supario,
How about 7805 fixed voltage regulator? I don't know it's current rating. But I think it should do. Otherwise you may have to go for LM317 variable voltage regulator.

subot_robot

ice
06-18-2005, 10:46 AM
Hey,


7805 current rating :: 1A if sufficient heat sinking is provided
LM317 rating :: 1.5A

Supario
06-18-2005, 10:41 PM
Hi,

The 7805 needs the input side voltage to be 3 volts higher than the output side voltage to work properly (ie the input voltage should be 8 or more volts). Im planning to have 6 ni cd cells on my robot which will provide only 7.2 volts and probably less when both the motors are drawing a lot of current. I tried running a 7805 on a 6 volt supply but it gave only 3.8 V output. I read that the MAX660 and LM2940 will work properly with 5.5V- 6V input and it would be nice to find something similar. I want to avoid having to putting extra batteries on board just to be able to run the voltage regulator.

Thanks
Supario

jack
06-18-2005, 11:29 PM
Yep, 7805 have 2-3volts drop across it, having poor efficiency. DC-DC converter is more efficient solution, sorry I don’t know about its availability.

Good luck

06-22-2005, 06:56 PM
You can get LM2940 at CeePee in SP rd. If they are out of stock try Vishal or Om.

Supario
06-23-2005, 01:31 AM
Hi,

Thanks for the tip. I found MAX660 in a shop on SP road (Ankit Corp), he wanted 250 bucks per piece (my jaw pretty much fell off). I didnt get anything in Om or Vishal either, Ill check in CeePee next time I go down there.
If you place an order with Maxim for free samples do they actually come? How long does it take?

Supario

ppppking04
11-16-2006, 08:17 AM
I know its a year late in reply but still...

Maxim does actually ship the samples (for free!) and do have a wide variety of LDOs

http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1131

Heres a good one...500mA output max current...plus adjustable output if required