LM2596/LM2676/LM22680 X GPRS Power Supply

Jeferson Pehls

Other Parts Discussed in Thread: LM2596, LM2676, LM22680, LM22680EVAL

Hi.
I have a GPRS product based on an embedded module.

This GPRS module have a power supply with a 4,2V output with a maximum medium of 300~350mA current consumption.

Curently, I am using a power supply based on a LM2596 (fsw = fixed at 150Khz only). Since a all GPRS modules present a high peak current consumption during data transmissions, I think I will need a faster power supply.

I saw the LM2676 have fsw fixed at 260KHz, and I think I will start using it instead of keep using the LM2596 - SMD TO263. I will update the power supply next month and the controller IC is one of the key parts of the power supply.

I was also thinking to use the LM22680 SMD SOIC-8 for this design

Input voltage range is from 10 to 32V only.

Question:
Is LM2676 or LM22680 suitable for my project? For GPRS modules?
Please give me some other suggestions, if possible.

What is the part numbers of developments boards for these ICs?

Please check the attached PDF. It shows the power supply requirements.

0820.GPRS_power_supply_specs.pdf

http://www.digikey.com/scripts/DKSearch/dksus.dll?Detail&itemSeq=117672525&uq=634795359243376141

http://www.digikey.com/product-detail/en/LM22680MRE-ADJ%2FNOPB/LM22680MRE-ADJCT-ND/1993220

I also would like to know which value range (if there is a standard value) of ferrite beads I could use between the power supply output and the power supply pins of the GPRS module.

Regards.

over 13 years ago

0 Jeferson Pehls over 13 years ago

Expert 1160 points

Help?

0 Marc Davis-Marsh over 13 years ago

TI__Genius 10115 points

Hi Jeferson,

THe LM22680 should work for this design, but because of the high frequency noise spec you will need to be very careful with layout and the output filter componenents.

I asked someone to take a look at this design in more detail, and they should have some more information next week.

Regards,

Marc

0 Jeferson Pehls over 13 years ago in reply to Marc Davis-Marsh

Expert 1160 points

Hi.

And how about the LM2676 for this design? It has a fixed switching frequency of 260Khz.

And if I use a LM22680 for the new design, which switching frequency range would be suitable for GPRS? I know it has adjustable frequency, up to 1MHz

0 Jeferson Pehls over 13 years ago in reply to Marc Davis-Marsh

Expert 1160 points

Hi.

Do you know when this person will be able to help me? I want to start updating the hardware soon.

Thanks

0 Giuseppe Pinto over 13 years ago in reply to Jeferson Pehls

TI__Expert 3950 points

Hello Jeferson,

we are working on it and we'll let you know as soon as possible.

Regards,

Giuseppe

0 Jeferson Pehls over 13 years ago in reply to Giuseppe Pinto

Expert 1160 points

Hi.

Thanks.

We really need a good solution for this case, because we will update the hardware of a current design, and we have a relative high volume for this product.

If the results with this new hardware be good, we would like to use the same power supply for all of our products based in GPRS/GSM. We are looking for a single solution for all products. We have many many products in development needing this solution.

Regards.