Electronics > Projects, Designs, and Technical Stuff
What adjustable linear regulator to use?
LukeW:
Are there any good candidates for a "jellybean" stock part as a more modern replacement for the 317?
In particular, I'd like an adjustable linear regulator to meet the following requirements - any recommendations? Thanks!
500 mA max load
0-5V out
"Rail-to-rail" output voltage, all the way from 0 to 5V.
Adjustment with a manual 10k pot, ideally output voltage should be linear with respect to pot position.
awallin:
you'll get as many part-suggestions as replies to this one :-//
my go-to LDO lately has been LT1963.. but I'm sure someone will quickly inform us about a cheaper and better part!?
https://www.analog.com/media/en/technical-documentation/data-sheets/1963aff.pdf
coromonadalix:
The lm317 has 2.5v dropout
LD1086 LT1083 LT1086 they have 1.5v dropout
LT1085 has 1v
LM1117 has 1.2v
But many of them (3 legged to220) wont go at zero untill you null out the adjustment pot with a negative voltage, like the lm723 ....
Ultra Low Dropout LDO regulators
https://www.st.com/en/power-management/ultra-low-dropout-ldo-regulators.html?querycriteria=productId=SS1733
bd139:
LT3080. The thing is the bee's knees!
https://www.analog.com/media/en/technical-documentation/data-sheets/3080fc.pdf
1. Max 1A out
2. Current referenced so goes down to 0V
3. 350mV dropout
4. Single resistor programming
5. Stable with small output cap
Look at the application notes under "lab power supply". That sounds like what you need.
They cost 10x what an LM317 does however in low quantities.
Zero999:
Most regulators don't work down to 0V, without a negative power supply. The LT3080 has a minimum load current requirement which means a current sink is required for it to work down to 0V with light loads. Unfortunately such a current sink would require a negative supply to get a true 0V out, although a current mirror does a reasonably good job of getting close without a negative supply.
Navigation
[0] Message Index
[#] Next page
Go to full version