Inrush Current Chip for PS/2 Design

Shmuel Davis

Other Parts Discussed in Thread: TPS25221, TPD1E05U06-Q1, TPS2041C, TPS2552D, TPS2553D, TPS2051C

I am currently designing a USB to PS/2 project where I have to provide +5V supply on an output connector. I am interested in adding the appropriate inrush current protection required for such a design. Someone suggested to add an inductor in series. However after a little research this sounds like it would cause unwanted ringing in my system. Do you have another solution that you would recommend ?

over 3 years ago

0 Chuck Branch over 3 years ago

TI__Mastermind 32681 points

I suggest that you look at our portfolio of charge port controllers.

https://www.ti.com/power-management/usb-power-switches-charging-port-controllers/products.html

With the limited amount of information that you have provided, it would be difficult to direct you to the best product. All of these devices will provide output current limit which is what you require in your system.

Regards,

Chuck

0 Bob Ma over 3 years ago

TI__Expert 8980 points

Hi, Davis,

Thank you for reaching out. Sounds like you need a power switch for inrush current protection. Please have a look at our latest power switch TPS25221, 2.5V-5.5V adjustable current limit power switch.

For more power switches, please check our selection guide. There are many kinds of power switches, including different current level, Vin range, packages, enable high/low, fixed/adjustable current limit, channel number, with/without discharge and so on.

https://www.ti.com/power-management/usb-power-switches-charging-port-controllers/technical-documents.html?keyMatch=POWER%20SWITCH%20SELECTION%20GUIDE

Regards,
Bob

0 Shmuel Davis over 3 years ago

Expert 2930 points

Thank you for your replies - It appears the PS/2 spec defines a Max of 275mA - thus I assume a current limit of 500mA would be more than enough ?!

Which would be better a Charge Port controller or a Power Switch ?

The package size is less important and the voltage range is 5.0V +/-0.5V !

Don't need Enable, single channel required only, and adjustable current limit not needed but would be "nice" to have

0 Shmuel Davis over 3 years ago in reply to Shmuel Davis

Expert 2930 points

Also I will need ESD protection on the Data and clock lines. We have the TI TPD1E05U06-Q1 stocked - do you know if this is good enough ?

0 Bob Ma over 3 years ago in reply to Shmuel Davis

TI__Expert 8980 points

Hi, Davis,

TPS25221 provides adjustable current limit from 0.275-A to 2.7-A, it should be a good choice for you. Or you can choose TPS2051D, it's a fixed 0.5A power switch with 0.85A current limit.

For TPD1E05U06-Q1, you can submit a thread then its team member will reply you.

By the way, can you let me know more about your product? USB to PS/2, what product it is?

Bob

0 Shmuel Davis over 3 years ago

Expert 2930 points

Do you have an alternative to the TPS25221 that is stocked \ available for purchase now ?

Does the TPS25221 have enough ESD protection or would I need to add an additional ESD protection diode to protect the +5V ?

0 Bob Ma over 3 years ago in reply to Shmuel Davis

TI__Expert 8980 points

Hi, Davis,

TPS2552D, TPS2553D, TPS2051C, TPS2041C can be alternative, but I afraid they are also out of stock.

TPS25221 ESD level is stated in datasheet, please check if it works for you.

For ESD on OUT pin, I think it's fine because there will be big cap on it.

Bob

0 Shmuel Davis over 3 years ago

Expert 2930 points

Dear Bob,

Thanks for your replies.

As an alternative couldn't I just use a resettable fuse instead of a Current Limited Switch ?

Regards

Shmuel

0 Bob Ma over 3 years ago in reply to Shmuel Davis

TI__Expert 8980 points

Hi, Shmuel,

That might be an option. Please submit a new thread for e-fuse recommendation. I will close this thread first, let me know if you get more questions.

Bob

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Inrush Current Chip for PS/2 Design