5v 2amp ldo/smps/regulator

hi

can anyone suggest me a cheap regulator/ldo which can provide 5v 2amp power. right now i am using lm2576 5v 3amp but it also requires 100uH inductor, 1000uF capacitor and 15watt diode. i require ic with lower external components, ideally no external components and at least it should not have inductor. so that i can save some pcb space.

thank you

can anyone suggest me a cheap regulator/ldo which can provide 5v 2amp power. right now i am using lm2576 5v 3amp but it also requires 100uH inductor, 1000uF capacitor and 15watt diode. i require ic with lower external components, ideally no external components and at least it should not have inductor. so that i can save some pcb space...

Click to expand...

For 2A output any regulator will require some capacitors, and 1000uF will be here or there ..
The trade-off between a linear regulator and a switching regulator is that the latter needs a “small” inductor”, whereas the former needs “reasonable” heatsink.
I think heatsink is bigger, as far as sizes are concerned.

Also, you have mentioned 15W diode.
What is it?

The LM2576 needs a 3A Schottky barrier catch diode, that is, its size is roughly the size of a half of a peanut.

In conclusion, a linear regulator requires 2 caps on input and 2 caps on output, and a big heatsink.
Switching regulator (LM2576) needs one cap on input, one cap on output, catch diode and an inductor, and a tiny heatsink.

:wink:
IanP

thank you,
i came to 15W figure because i though 3amp X 5v = 15, i am using MBR360 diode.

why bother to build one ? buy a ready made they are so cheap.
**broken link removed**

If you're using a switching regulator, that inductor and diode will be required along with the caps. With that you get greater efficiency than a linear regulator, meaning a much much smaller heatsink which would add to cost, size (space) and so it's also better for nearby components such as capacitors as well as better for the regulator itself.
Using a linear regulator, you could get away with 1 or 2 capacitors, but the heatsink would totally kill your purpose, especially if it's operated with a high input voltage. I think it's better for you to stay with the current design employing the LM2576.

If your circuit can do with max 1.5A, you can use the L4971. The attractive feature here is that the regulator has an 8-pin PDIP package, but it requires more parts.

Hope this helps.
Tahmid.

Hi Tahmid thanks for the insight, i'll go with current design..

---------- Post added at 17:12 ---------- Previous post was at 17:05 ----------

Kripton2035 said:

why bother to build one ? buy a ready made they are so cheap.
**broken link removed**

Click to expand...

thanks, but i need a cheaper solution..

does lm2576 uses low frequency oscillator to output correct voltage? in lm2576 circuit if i change 100uH with 1mH inductor and 1000uF with 100uF capacitor then will i get the same results?

Use LM2576T Simple Switcher.. low cost, low part count... wide input range... go through it

Check ST Micro site, its online design tool helps to complete circuit for SMPS.https://my.st.com/

why dont you use lm5576

you will resolve most of your problems.......

---------- Post added at 01:11 ---------- Previous post was at 01:05 ----------

devil6600 said:

does lm2576 uses low frequency oscillator to output correct voltage?

Click to expand...

52 kHz fixed frequency internal oscillator for lm2576