Pololu 4-25v boost regulator

Hi i purchased two of these, i am going to run 4 goldspark motors which have a stall current of 1.3A
since this thing has a current limit of 2A would it cause any issues?

also i am guessing since i have 4 motors i would need to use two of these due to the current limit?


You might be able to use only two regulators if the input current of the regulator stays below 2A. The input current will be affected by the current draw of the motor as well as the input and output voltage. To get an idea of the amount of output current the regulator can supply, you might refer to the charts found in the “Efficiency and available output current” section on the regulator’s product page that show the performance of the regulator at various input and output voltages.

- Grant

thanks for the reply, yeah i saw the charts. Although i am still not clear on certain things.
The motors will be run at 7.4V and powered through a 11.1 2.2maH lipo battery. At max efficiency they draw 0.34A and they stall at 1.3A. since they will be on a sumobot they will never be in a position to be at stall speed since the wheels wont have enough traction to hold them to that point.

i did a few test with the voltmeter and my hand, although not a 100% accurate, i saw current draw shoot up to 0.8A. looking at your chart the closest chart i saw was the one with the vin 9v- vout 12v, how much different would it be with my 11.1-7.2v range? i am guessing around 80-90%?

you said that i might be able to use only two, by that do you mean that i might need more?

It sounds like you are trying to reduce the voltage from your battery rather than boost it (11.1V in and 7.4V out). If that is the case, you should use a step-down voltage regulator or step-up/step-down voltage regulator. For the specific voltages and current you mentioned, you might consider our adjustable 4-12V step-up/step-down voltage regulator. With those regulators you would probably be able to connect two motors to one regulator.

However, since you are trying to drive your motors at a lower voltage than your input voltage. you could limit the duty cycle of your motor driver to effectively limit the voltage applied to your motors instead (assuming you are using a driver).

- Grant

actually i am using 2 TB6612FNG, so if i understand you correctly, i can still use the 4-25v boost regulator with the 2 motor drivers?
the reason i am using the boost regulator is that i plan on doing PID, and since after tuning the PID with a certain voltage any changes in the voltage will change the motor speed, so with that it will also skew all the PID tuning creating unpredictable behavior.
hope that make since

forgot to mention, i will also be adding an lm317 to regulate the voltage to the mcu and sensors at 5v.

No, a boost regulator is not appropriate for converting 11.1 V to 7.4 V, and setting the output voltage lower than the input voltage on a boost regulator could damage it.

- Grant