TPS92630-Q1: VSNS connection when the current sense is not used

Hi Frank-san,

Thanks. However, my customer can't tie each VSNS pins to IOUT1,2,3 individually because of a PCB area restriction.

So, could you check if VSNS1,2,3 can be connected together to IOUT2? (Again, customer doesn't use the short detection.)

If this connection is not acceptable, they can't use TPS92630-Q1.

Also , could I add one more question?

As I mentioned, customer doesn't use IOUT3. Datasheet says that PWM3 pin need to connect to GND when IOUT3 is not used.

It is difficult for customer to tie PWM3 pin to GND because of limited PCB area. So, they wants to leave PWM3 floating.

In the case that PWM3 is floating, how does IOUT3 work? If you don't recommend PWM3 is floating, could you teach me the reason?

Regards,

Saito 

Hi Saito-san,

1) Could you offer the schematic or tell me whether customer use pwm dimming or supply dimming, the PWM pin is controlled individually by MCU or just connect to supply line with divided resistor. It's necessary for me to tell how to connect the Vsns pin.

2) About "It is difficult for customer to tie PWM3 pin to GND because of limited PCB area", i can't understand it.

For TPS92630-Q1 there is a thermal pad that help to dissipate thermal,  and the thermal pad connect to GND. So customer just need to connect the VSNS3 to thermal pad on PCB layout to realize connecting to GND. I don't find any difficult. 

Hi Frank-san,

Can I send you an email about this topic?

I want to share the schematic.  Customer wants to get these answer in this week. So, I greatly appreciate your  kind support.

Regards,

Saito