TPS61098: RIN resistor

K.Hamamoto

Guru 12155 points

Part Number: TPS61098

There is RIN resistor between SW and VIN. How can we calculate the value of RIN?

Is RIN=470ohm possible?

Best Regards,

Koji Hamamoto

over 5 years ago

0 Jasper Li over 5 years ago

TI__Mastermind 46905 points

you mean the voltage between the power supply and the VIN pin. the 470ohm is also good.

0 K.Hamamoto over 5 years ago in reply to Jasper Li

Guru 12155 points

Hi Jasper-san,

Thank you for your prompt reply.

I mean the resistor which is between supply power and VIN pin.

How can calculate the resistor?

(VIN pullup to supply power by 400ohm and the quiescent current into VIN pin is 4uA (max). So, the drop voltage is 1.6mV.

Is that correct?)

Best Regards,

Koji Hamamoto

0 Jasper Li over 5 years ago in reply to K.Hamamoto

TI__Mastermind 46905 points

it need to set the time constant to approximately 400R*0.1uF, small resistor would result in large capacitance, large resistor can reduce the capacitor, but result in large difference voltage between supply voltage and VIN voltage. so the resistor should be at this range or it is better if it is lower.

0 K.Hamamoto over 5 years ago in reply to Jasper Li

Guru 12155 points

Hi Jasper-san,

Thank you.

Regards,
Koji Hamamoto

Power management

Power management forum

TPS61098: RIN resistor