Unused pins for CY7C65631-56LTC

[NoAr_1540581]

Hello

Q1) Please tell me recommended Pin connection if unused  the following pins.

- OVR#-----Since it is an input terminal, is a pull-up connection good with a VCC power supply of 10 kΩ?)

- PWR#

- EEPROM SPI I/F

- DownStream Port

Q2)

About SELFPWR pin. I am checkin the reference circuit (CY4606), there is a 10k Pulldown,  2.2uF capacitor, and  680Ω resistor. Could you briefly explain the reason why each is needed?

- 10k pull-down

- 2.2uF

- 680Ω

Best Regards

Arai

[Sananya_14]

Hello Arai-san,

1. Yes OVR# can be connected with a pull-up of 10K. The PWR#, D+/D-, SPI_CS, SPI_SCK pins can be left unconnected. The SPI_SD pin should have a pull-down of 15K as mentioned in the datasheet.

2. We recommend a 10K pull-up or pull-down on the SELFPWR pin as per the datasheet. The additional components seem to be added in the DVK for decoupling and to limit the current at the pin.

Best Regards,

Sananya

[NoAr_1540581]

Hello Sananya san

>2. We recommend a 10K pull-up or pull-down on the SELFPWR pin as per the datasheet. The additional

> components seem to be added in the DVK for decoupling and to limit the current at the pin.

→

Could you please tell me in detail what the intention is for current limitation at the pin mentioned above?

As the direction in which the current flows is the HUB side,  If there is a series resistor, the voltage will drop as the current increases. I couldn't imagine the intention of current limitation, so please explain.

 Best Regards

Arai

[Sananya_14 · Accepted solution]

Hello Arai-san,

I checked internally with the design team and the 680ohm resistor is not needed on the SELF_PWR pin. It may have been added for specific DVK design at that time but we only recommend the 10K pull up/pull down for customer designs.

Best Regards,

Sananya