How to supply power to SIM300 without using battery?

[MScofield]

Hi all,

Which is the best way to supply the 4V/2A voltage/current to the sim300 module, if you don't want to use a battery.

One can use a voltage regulator like LM317 or a cheap solution like a zener diode between the main voltage and the module VBAT pin.

Im my oppinion, the LM317 does not fit for the solution because it can supply 1.5A, and the zener solution does not give a estable current source.

What is your suggestion?

Thanks in advance.

 

[GSM Man]

sim300 power

You need a good regulator - a zener will not work reliably.

An LM317 is OK if you don't have a large Vin-Vout differential voltage. The average current draw of the radio is under 550ma so the power rating shouldn't be a problem. However, the radio can draw as much as 2A while transmitting so you need to be careful that your power supply design has good load regulation and low-ripple. This typically means you need to place a load cap on the output of the regulator and a cap on the adj pin. Check the manufacturers data sheet to see what they recommend.

You also have to be sure to supply good bypassing at the radio power pins. This means a low ESR (< .200 ohm) tantalum cap and a .1 - 1uF ceramic in parallel. They must be placed as close to the radio power pins as possible. Also, good grounds and low impedance power traces are important.

 

[MScofield]

sim300 to php

Thanks for the answer!

Then what 4V voltage regulator you can suggest? what is widely used for for hw designers, like LP2981 form National, for example. Even though it draws in excess 100mA, one can use a current driver.

 

[vamsi.kodati]

sim300 supply

Use TPS72501 LDO by texas instuments which can b programmed by setting resistor values to give 4V and even 4.2V n so on till 5V and can support current upto 1A. Don worry abt the the transmit burst, it takes current till 2A only in spikes for which capacitors will provide protection. I power my sim300 with this LDO and its working fine. Except for transmit burst which is an infrequent event most of the times the current consumption by sim300 is much always lesser than 1A.

 

[leilarazavi2000]

sim300 + power supply

use LM338 . adjustable and 5A .

 

[pranam77]

sim300 power supply voltage regulator

LM338 can aslo be used as sugested by"leilarazavi2000" but even LM317 TO220 package can be used for better current capacity which is sufficient for SIM300 module.

 

[GSM Man]

sim300+capesitor

You don't need to a high-current regulator. The module only draws a lot of power for very short periods of time. The average current draw is typically about 200 - 300mA, depending on the band and operating mode. A LM317T (1.5A) works fine - that's the regulator I use in all of my GSM products.

More inportantly, you need a power supply that is well regulated and well filtered. Make sure that the ripple voltage is low and that the regulator has the proper loading capacitors on the input and output. Also, you should have a low-ESR filter cap close to the module's power pins (100uF or greater), along with a .1uF ceramic cap. Also, I recommend running the power supply at 4.2V. This provides some overhead to allow for some power supply voltage dips.

I've seen a lot of marginal power supply designs, and it's always been that they are not properly filtered. I've never seen a problem with the regulator not being able to handle the currrent draw.

 

[nxavier]

power on sim300

hi.

been reading this thread and i found it useful as we are also planning to use this module and i am assigned to work on the power (external and not battery).

but i still have a question. we are planning of using 4 of sim300d modules on a single board. would you still recommend the regulators you have been using for this design? or i should find another regulator that can generate more power?

in addition, if we have this 4-module design, will it be sufficient to place large capacitors before each module input to compensate its 2A pulse consumption of it all depends on the regulator.

your views are very much welcome.

thanks in advance.

 

[GSM Man]

sim 300 power supply

I would recommend you provide a seperate voltage regulator for each module.

 

[jeffry_vb]

4v 2a psu

can someone attach the schematic of LM 317 that is no problem wih 2A current supply for SIM300??

 

[GSM Man]

power for sim 300

See this post, it has a schematic that will work

 

[nxavier]

sim300 burst

I would recommend you provide a seperate voltage regulator for each module.

wouldn't it be space consuming if we have a separate regulator for each module? We are actuary trying to minimize the area. I've thought of using a 2A regulator then in the output, there will be 4 capacitors (in parallel) for each module. These capacitors should handle the 2A-surge current of the module.

is this set-up ok?
thanks.

 

[rongo024]

sim300 Power Supply

MIC29302WT

 

[microembedded]

sim300 Power Supply

I am using LM317T and it will over heat if you use voice call functions for few minutes and rest everything working fine without any problem..

 

[bikashh]

Re: sim300 Power Supply

hi friends i m new to this forum....
you people better use LM2576T-5.0 which is a fixed 5 v,3A regulator with few external components. you can step down this 5v to 4.3v by connecting a diode at its output and use it for SIM300 module. 4.3v is under tolerable range.