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Im trying to learn robotics with raspberrypi but im having a problem. I have 6 AA batteries in a batteryholder that are connected to a breadboard and with M-M jumping wires its connected to a LM2596S adjustable voltage regulator module, Which then is connected to the raspberryPi with M-F jumping wires.

I turned down the V provided to about 5V which is recommended, but as fast as I plug it in to the Pi it drops down to about 4V which is not enough power for the pi to run and makes it shut down. I have tried adjusting the power (out) to 6V and 7V but the same thing keeps happening when I connect it to the Pi, the V (out) drops down to 4V. The V (IN to the module) shows about 8.2V when not connected to the pi, but drops down aswell as soon as I connect it.

The first time It was plugged in to the pi it worked but now all of a sudden it has stopped working. I bought a new voltage regulator but the same thing keeps happening. What should I try?enter image description here

  • (1) I suggest to replace AA batteries by a rechargeable Lipo battery power bank, which gives higher current and lasts longer. (2) Do not set LM2596 voltage output higher than 5.25V for Rpi. Higher voltage overloads the Rpi's voltage regulator, heating up components and shortens Rpi's life. (3) Do not connect LM2596 output to Rpi 40 pin connector. Instead, connect it to the Rpi3B micro USB connector: raspberrypi.stackexchange.com/questions/98715/… – tlfong01 Aug 9 '19 at 10:52
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    The problem is that your AA batteries are unable to supply enough current (Amps) and maintain a high enough voltage for your regulator to continue supplying 5v. It looks like your regulator requires a minimum of 7v input, 6 AA batteries when fully charged and healthy and importantly being asked to delivery current within their capability will deliver around 9 volts. But if you try and draw more current than they are capable of supplying the voltage will drop. That is what is probably happening here. – Charemer Aug 9 '19 at 15:24
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"What should I try?" A PROPER power supply.

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    ... Or a bigger battery Able to supply the required current at or above the regulator required voltage. – Charemer Aug 9 '19 at 15:18
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I suggest you buy a UBEC. They are inexpensive (a few UK pounds from eBay) and efficient and will get the most out of your batteries.

https://en.wikipedia.org/wiki/Battery_eliminator_circuit

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  • A battery eliminator circuit - also known as a power supply or PSU. – Charemer Aug 9 '19 at 15:26
  • Not sure why the downvote, I assume joan was referring to BECs used in the R/C world where traditionally one had a large battery for motive power and a secondary battery for the control electronics. The purpose of the BEC is to eliminate the secondary battery. This could be a reasonable suggestion given the OPs photo of their use-case. – Glen Yates Aug 9 '19 at 20:33
  • @GlenYates Yes, the common UBECs which take a voltage between something like 6V-26V and efficiently produce 5V (3 amps being a common capacity). They are pretty useful for battery powered Pis. – joan Aug 9 '19 at 20:39
  • Sorry guys all this is very new to me, if I decide to go for a Lipo battery power bank, how many mAh should it have? @tlfong01 – Leobd Aug 10 '19 at 6:52
  • Sorry guys all this is very new to me, if I decide to go for a Lipo battery power bank, how many mAh should it have? @GlenYates – Leobd Aug 10 '19 at 6:53

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