TPS53632: TPS53632 minimum Vin requirement

Hi Derrick,

Thanks for your quick response.

According to "The minimum input voltage is lower for lower freq and/or lower output voltage", what about the output voltage is 0.95V and freq is 800kHz, would you help me to find out what's the minimum input voltage for that based on your calculation?

Thanks,

Zane

Hi Zane,

if so, then it's approximately 3 times output voltage. 0.95*3 = 2.85V. The battery power(3V~4.2V) could be sufficient.

Hi Derrick,

Thanks for your explanation.

Just for curious, if using 3-phase, will you use different estimation to calculate minimum Vin?

I have another question. Is the TPS53632 a digital DC/DC controller or an analog controller w/ digital wrapper?

Thanks,

Zane

Hi Zane,

Based on the calculation, whether 2-phase or 3-phase operation the input voltage could be lower than 3V after considering the Toff limitation.

But there is another rule describe in the datasheet “The input voltage (VVIN) does not include a UVLO function, so the circuit runs with power inputs as low as approximately 3 x VOUT”

So, it should be the similar to 2-phase or 3-phase operation.

TPS53632 is not a full digital controller which embeds a micro processor or something. It’s an analog control loop with digital NVM to tweak parameters.

Hi Derrick,

Thanks for your details.

We were hesitating to use TPS53632 in our application due to "7.3.15 Input Voltage Limits". After go over your explanation, we have more confidence to use this part.

May I know what that Toff limitation is? 

Thanks,

Zane

Hi Zane,

Which means low side MOSFET turn-on duration. Device needs this time frame to execute some internal mechanism.