LDO for STM32L433?

[AStol.2]

Hello, I would like to know what LDO regulator you recommend to use in my development, it uses a 7.2V Lithium battery pack. The application uses 5 GPIO's (4 output, 1 input), 1 I2C, 2 USART, 1 LPUART.

[TDK]

Powering 3.3V with an LDO from a 7.2V supply is going to cause a lot of heat. Whatever you choose, make sure it can handle that much.

If you use 100mA, the LDO is going to dissipate 100mA*(7.2V-3.3V) = 0.39W. Not a ton, but substantial. A buck converter would be more efficient.

[gregstm]

It would be helpful to know how much current your micro+peripherals will consume. Is any part of your design sensitive to power supply noise? If it is just a few milliamps and you need a low noise power supply, then a small linear regulator might be the way to go... It all depends what is important to your design eg. low cost, battery life, low noise, low shutdown current, small size,...?

[AStol.2]

Hi, thanks for replying.

The uC will have its own regulator, the question is if a 150mA regulator is enough to power the uC?

On the other hand, what TDK clarifies is true, that is why the 7.2V pack first goes a main regulator that reduces it to 4.2V and then goes to the regulator dedicated to uC. My question is related to the regulator dedicated only to uC.

[TDK]

> The uC will have its own regulator, the question is if a 150mA regulator is enough to power the uC?

It depends on your particular application, but 150mA is very likely more than enough power. I don't think I exceed this in any of my applications. Higher capacity LDOs are easy to find though.