TPS22992: Questions about charge pump frequency

aurelienr

Part Number: TPS22992

Hello,

I may use this TPS22992 switch for powering a LTE modem.

VCC = VBIAS = 3.8V

I'm wondering about the frequency of the chargepump. I have an analog section in the product that would be very sensitive to noise frequencies between 8 and 20kHz. Usually chargepumps are considered as noisy devices and often operates in this frequency range, but what about this small integrated charge pump ? What would be its frequency in steady ON state ?

Thank you

Aurelien

6 months ago

0 Patrick Shalton 6 months ago

TI__Mastermind 19580 points

Hi Aurelien,

Since the TPS22992 charge pump is so small, it should not create any substantial system noise. However, you may be more interested in TPS22950, which does not have any charge pump yet retains a relatively low Ron. Will this device work instead?

Thanks,

Patrick

0 aurelienr 6 months ago in reply to Patrick Shalton

Intellectual 360 points

Hello,

Thank you. I agree that the noise should be very low, because of low gate leakage. I will make a try.

The alternate reference has a too high Rdson, I would prefer to stay below 0.02 Ohms max.

Aurelien

+1 Patrick Shalton 6 months ago in reply to aurelienr

TI__Mastermind 19580 points

Hi Aurelien,

Understood, thank you - please let me know if you have more questions on this, or if you run into noise issues from this device.

Thanks,

Patrick

+1 Patrick Shalton 6 months ago in reply to Patrick Shalton

TI__Mastermind 19580 points

Hi Aurelien,

I'd like to update you that the charge pump frequency does not interfere with your 8-20kHz sensitivity range. Best on your design!

Thanks,

Patrick

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TPS22992: Questions about charge pump frequency