How to raise Switching Mode PS output current

Thread Starter

abdulbadii

Joined Aug 30, 2017
85
How do we manage to raise Switching Mode PS output current having 3 pin of 2 voltage output and specs :

Input 220V 800 mA
Output
16 V 500 mA
32 V 370 mA

DC voltage was measured correctly by DMM

Need arise because instead of performing DC PS, it and/or its load do stutter, on 16V output, with idle interval around a second as it's being loaded with a RS385 DC motor which runs normally on other PS

Is raising the current output, maybe by replace few capacitors' rating or others' with higher ones, would be the easiest, practical solution and really safe method used commonly, or the SMPS does have some trouble and faulty in some circuit part ? If such above hints it really has some faulty, in which part it'd usually be?
 
Last edited:

Papabravo

Joined Feb 24, 2006
21,159
How do we manage to raise Switching Mode PS output current having 3 pin of 2 voltage output and specs :

Input 220V 800 mA
Output
16 V 500 mA
32 V 370 mA

DC voltage was measured correctly by DMM

Need arise because instead of performing DC PS, it and/or its load do stutter, on 16V output, with idle interval around a second as it's being loaded with a RS385 DC motor which runs normally on other PS

Is raising the current output, maybe by replace few capacitors' rating or others' with higher ones, would be the easiest, practical solution and really safe method used commonly, or the SMPS does have some trouble and faulty in some circuit part ? If such above hints it really has some faulty, in which part it'd usually be?
An SMPS (Switch Mode Power Supply) is designed from the ground up to a set of performance requirements. You can't just go in and modify components without a complete redesign. Most likely you would need a different inductor and maybe a different power switch and certainly lower ESR capacitors. The easiest, cheapest, safest and most reliable method is to search for a new and more capable DC-DC converter.
 
Last edited:

AlbertHall

Joined Jun 4, 2014
12,345
As you can see from the datasheet extract below, the motor can draw a lot more current than your supply is capable of. In particular when the motor is first switched on it will (attempt to) draw the stall current - 4A.
1625392869116.png
 

Ian0

Joined Aug 7, 2020
9,668
Assuming that the power supply is a flyback circuit, the only way it can output more energy is to store more energy in the inductor (transformer) core.
Unfortunately, to make it as cost-effective as possible, it will have already been designed to use the core to its maximum (i.e. saturation).
In other words, if you want more output you'll need a bigger inductor (transformer).
 
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