I can control 1A through LM350!

[markrod]

schematic lm350

Hi,

Im designing a power supply for a gsm module. It requires a supply voltage of 3.3V and can provide up to 3A. The module on the average uses only 880mA but uses up to 3A under certain conditions (transmitting, etc). Im thinking of supplying the module with around 1A and then add a capacitor to meet the 3A requirement.

Im using an LM350 to regulate my voltage. Im already getting the exact voltage that i need. I just cant get the 1A that i also need. The circuit i used is the one shown in the schematic diagram of the LM350.

Can anyone give me an advice on how to control the 1A that i need?

 

[IanP]

Re: LM350 Help

The LM350, or any other voltage regulator, can deliver the rated output current under the condition that the input regulated/unregulated source can supply voltages ≥ (Vout+3V) @ the required output current ..
If the input condition is not fulfilled then don't expect the output to follow anything ..
Big input smoothing capacitors may help for some ms, but they will not provide power for ever ..

Ensure that the unregulated side can supply sufficient current and you will be OK ..

Regards,
IanP

 

[markrod]

Re: LM350 Help

ah okay got it! Thanks! If that's the case then a capacitor would do for the 3A burst, especially since the burst would only last for around 600us.
Thanks!