USB superspeed peripherals Forum Discussions

[Zac0218]

Hi,

This is Zac from HPE.

We used CYUSB303X on one specific board for a while but now we need to migrate few power ICs to other vendors due to component shortage.

I notice that the CYUSB303X specified the voltage ramp up rate in the datasheet.

Our new power IC has similar 1.2V output ramp up rate which is close to CYUSB303X's: 50V/ms.

I'd like to know whether it's going to raise any concern or not.

Kindly advise.

Much appreciated.

[JayakrishnaT_76 · Accepted solution]

Hello,

Please let us know the ramp up rate of the power IC.

As mentioned in the datasheet of CYUSB303x, if the ramp up rate is less than 50V/ms, then it should be fine.

[Zac0218]

Hi Jaya,

Thanks for the prompt reply.

The core 1.2V VDD ramp rate is about 80us which is 15v/ms.

However, the IO 3.3V ramp rate is larger than 50V/ms.

Will it be a concern?

[JayakrishnaT_76]

Hello,

Yes, it will be a concern. As mentioned in the datasheet, the Core and IO supplies can have a maximum ramp up rate of 50V/ms only. We strongly recommend to follow the limits of each parameters mentioned in the datasheet.