Lost power to Pololu stepdown voltage regulator D15V35F5S3


Im having a problem with the Pololu step-down voltage regulator D15V35F5S3. Im wondering if antone could help me solve this?
I have a lighting system which only needs 5V to operate. I have a 9V battery connected through the terminal blocks which is connected to the Pololu step-down voltage regulator D15V35F5S3 by a 2 pin wire. Then the Pololu step-down voltage regulator D15V35F5S3 is connected to the lighting system by a straight male header strip and a 2 pin wire.
My problem is, that the lighting system works for only 10 mins then it shuts off. there are no other lights on. I’ll disconnect the battery and reconnect it, and the lighting system works again but only for a few seconds then it shuts down with no power. I figure that Im losing power through the regulator? or may be difective? But, I also think it may be it is under voltage and shuts off.
here is a video of what I mean

Can you help me please?
thanks for the help

Hello, Robert.

It sounds like your problem could just be that your battery is dying after about 10 minutes, which doesn’t seem unreasonable for a 9V battery. Have you estimated or measured how much current your system is drawing? In general, 9V batteries are very poor choices for high-current applications: they have very low capacities, so they will not last long, and they cannot deliver very high currents. Have you considered switching to a more appropriate power source, like a wall power adapter or a rechargeable 8.4V AA NiMH battery pack, which could conceivably last more than 10x longer than your 9V battery?

- Ben

If you have a multimeter, you could try measuring the voltage on your 9V battery right after the regulator shuts down to see if the battery is dead. (You can also measure the voltage at various times while the lights are on to get an idea of how fast the battery is draining.)

- Kevin