TPS25961: TPS25961 - minimum pin gap

chris padbury

Part Number: TPS25961

Tool/software:

Looking at the datasheet of TPS25961, there isn't a directly dimensioned minimum distance between the pins and the exposed pad. I can work out a minimum distance indirectly by using the dimensions given:

(1.9mm - (1mm + 0.1mm) - 0.3mm - 0.3mm) / 2 = 0.1mm

but that seems unrealistically pessimistic. I calculate the nominal as 0.25mm. For my application, I need the minimum to be at least 0.15mm. Can TI confirm this dimension is at least 0.15mm?

over 1 year ago

0 Arush Gupta over 1 year ago

TI__Mastermind 39295 points

Hi Chris,

Yes, the calculation looks too pessimistic. As you mentioned nominal calculation is .25mm which will be the case for most devices.

I am getting a confirmation from product team regarding 0.15mm as minimum dimension. Please give us time till next week. I will get back to you as soon as I get the reply.

Best Regards,
Arush

0 Inemella Sai Bharadwaj over 1 year ago

TI__Prodigy 380 points

We have checked in model viewer, minimum distance between exposed thermal pad and pins is 0.25mm.

0 chris padbury over 1 year ago in reply to Inemella Sai Bharadwaj

Prodigy 70 points

The nominal of the drawing is also 0.25mm, so does the model viewer just represent the nominal. If so I need to know what tolerance should we apply to that?

0 Arush Gupta over 1 year ago in reply to chris padbury

TI__Mastermind 39295 points

Hi Chris,

We checked char data for this device. This is based on 30 device and this is just a reference.

Device width x_min = 1.970

Pin length max = 0.278

ground pad worst case from above diagram = 1.1

So new calculation becomes (1.970 - 1.1)/2 - 0.278 = 0.157mm > 0.15mm.

I hope this helps.

Best Regards,
Arush

0 chris padbury over 1 year ago in reply to Arush Gupta

Prodigy 70 points

Hi, Thank you for sharing this data which is good news.

To understand a minimum component count implementation, does TI advise against connecting EN/UVLO directly to VIN, even in applications below 5V? The TPS25961 datasheet shows an implementation for 3.3V and low current (copied below) that uses a 47k resistor pullup rather than a direct connection. Will a direct connection just increase pin leakage of is there any more significant reason to avoid?

0 Arush Gupta over 1 year ago in reply to chris padbury

TI__Mastermind 39295 points

Hi Chris,

For this device EN can be pulled up directly to the Vin for supply less than 5V.

Best regards,
Arush

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TPS25961: TPS25961 - minimum pin gap