Looking for 0.3Vout/0.2A converted from 3V3 input

Jason,

The lowest output voltage supported by our LDOs is 0.5 V from a traditional 0V GND reference. To get the output voltage to go lower you would have to regulate the GND pin of the LDO below the system level GND to make this possible.

The other thing you could try is margining the LDO as shown here:
training.ti.com/voltage-regulator-margining-precision-dacs
e2e.ti.com/.../give-your-voltage-regulator-the-margin-it-deserves

I have tried this before and it seems to work, but i have never taken the output voltage that low.

Regards,
Mark

The same margining technique can be used for a DC/DC as well. TLV62568DRL may be the smallest DC/DC to do this.

Chris and Mark,
thank you for your method.
How about using LM10010 + TLV62568 combination to achieve 0.3V/0.2A?

BR,
Jason

LM10010 looks like overkill. All you need is an analog voltage. This can come from an MCU, DAC, RC-filtered PWM signal (see www.ti.com/.../slva471.pdf), or voltage reference (TLV431-type).

If the current is constant you just use a 15 ohm resistor in series with the load.

Kevin is also correct if the current is constant you can use a resistor to drop the voltage to 0.2V, just keep the power dissipation in mind. And I also agree with Chris, to only do one voltage the LM10010 would make it fairly complex it would be better to use another rail and a resistor.

Regards,
Mark

Mark and Kevin,

The load current is not constant.

It is variety in 0.2A.

I have a TLV62080 EVM board on hand.

Assume using TLV431 as reference voltage as 1.24V, calculate the injection resistor based on feedback devider [178k(high side) and 39.2k (low side)].

And then, get around 37k injection resistor with 1.24V reference voltage.

But, I found that 0.3V output voltage will be changed by load current from 0.27V to 0.35V with 0.2A to 0A.

Does it cause by min duty cycle?

any switching device is more suitbale for this condition?

I would like to apply that EVM board to test it again.

BR,

Jason

It's probably a good idea to add an extra 22uF output cap to minimize the ripple in PFM at such low Vouts.

Where was the output voltage measured? Where is the TLV431 located, relative to the TLV62080 EVM? Can you share a photo of your setup?