TPS25830A-Q1: Lout and Cin selection

Hi,Yuta-san,

Q1. What your min Vin?

Q2. Beside EMI requirement, input ripple, I think other consideration will be "derating of ceramic capacitors", "long leads
from the automotive battery to the IN pin of TPS2583x-Q1", "cold or warm engine crank requirements".

Below is input capacitor selection guideline in datasheet FYI. 

11.2.2.5 Input Capacitor Selection
The TPS2583x-Q1 device requires high frequency input decoupling capacitor(s) and a bulk input capacitor,
depending on the application. A high-quality ceramic capacitor type X5R or X7R with sufficient voltage ratings
are recommended. To compensate the derating of ceramic capacitors, a voltage rating of twice the maximum
input voltage is recommended. The bulk capacitance selection depends upon a number of factors: long leads
from the automotive battery to the IN pin of TPS2583x-Q1, cold or warm engine crank requirements, etc. The
bulk capacitor is used to dampen voltage spike due to the lead inductance of the cable or the trace. For this
design, one 10 μF, 50 V, X7R ceramic capacitors are used. A 0.1 μF for high-frequency filtering and place it as
close as possible to the device pins. Consider adding additional bulk capacitance for operation through low VIN
warm-crank profiles is required by the vehicle OEM.

Regards,

Bob

Hello Bob,

Thanks for your answer.

For the Q1, the Vin range is 4.5V~16V.

For the Q2, thank you. I close this question.

Regards,

Yuta Kurimoto