Power supply without regulator

[Steven Bébin]

Hello,

I am currently working on my end of year project. I first realized my project under a development kit then now I realize the PCB.

I am currently facing a problem. I have an STM32L073RZ which I must supply. As a power supply, I have a Li-SOCl2 accumulator. The battery output voltage is 3.67V in open circuit and 3.6V at 1mA. The supply voltage of the microcontroller is 1.65V to 3.6V.

That's very fair, so I was thinking to use a 3.3V regulator. But the problem is that I have not found a regulator with low consumption. The lowest consumption I found is 40uA, it is very small but it halves the autonomy of my project !

So I wondered if it was possible not to use a regulator and directly power it with the accumulator. Knowing that the accumulator has a nominal voltage of 3.6V and at the end of discharge of 2V.

Thanks,

Steven

[MViei.1]

I would have the same question

[MasterT]

MCP1702 - 2 uA

AP7381 - 2.5 uA

Bad idea to not use LDO voltage regulator,

[LCE]

... and many more, check the TI LDOs, they have some with Iq < 1µA.

NEVER connect the battery directly!

[Peter BENSCH]

The STLQ020 might be an interesting alternative: 2-5.5V, 200mA, typ Iq=0.3µA

Regards

/Peter

[LCE]

🙂 Looks good, but no samples or at distri. available in SOT23-5, adj. or 3.3V :(

Just starting a new project where I could use these, too.

[MViei.1]

could you tell me why it is a bad idea? sorry really new here