9V battery problems powering ATTiny85

Hi, I’m having trouble powering my ATTiny85 device with a 9V battery. I’ve read that 9Vs suck, but they are the perfect size and shape for this particular device and I would like to find a way to use them.

The problem is that ONLY the older red Duracell ProCell batteries run the device properly (see pics). Any other battery, including the newer yellow ProCells, don’t work. They give the unit power (I can still press a button and the LED lights up), but the program runs erratically.

Why is this? I can’t find any of these red ProCells anymore…actually, I DID find a new one in a store, but it didn’t work either! Only older red ProCells work for some mysterious reason.

Please shine the light on my ignorance!

I may be a noob, but whats the mA capacity on them? I had the same problem before with my project and finding batteries to use it with. I had recently tried using a 9V battery (a cheap brand) and had my system acting erratically, so I changed to using multiple AA's/AAA's and it works so much better. Do you need exactly 9V to run your project? 4 AAA's are about the same size as a 9V and have much better capacity.

9V batteries are generally only 200-300maH. An AA is more like 2000-2500mAH

Maximum operating voltage for the ATtiny85 is 6V. Are you using a 5V regulator ?

You can get small Lipo batteries. (2S = 8.4V charged, 7.6V discharged, either of which is perfect for powering a 5V regulator.

you probably have more "play time" using 3-4 AA cells

3 AA cell = 4.5v 4 AA = 6v

do you have a simple volt meter to check the battery voltage while it is loaded with the device it powers? it could be the cells have no more "juice" left in them. without load they may measure 8-9v ... with load ... it could go right down to 3v

9V NiMH will give more current, try those. I don't see any reason to use batteries which aren't rechargable these days.

Operating Voltage
– 1.8 - 5.5V for ATtiny25V/45V/85V
– 2.7 - 5.5V for ATtiny25/45/85

The above is taken from datasheet. Using 9V can damage the chip. It may also cause malfunctioning.
Try 3 1.5v batteries in series.

Hi, I’m having trouble powering my ATTiny85 device with a 9V battery

I don’t know any way to interpret that statement that doesn’t result in the conclusion you already applied
9V to an ATtiny85, which almost certainly would have fried it.