BTF3125EJXUMA1 Layout recommendation

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
gunasekart
Level 2
Level 2
10 replies posted 5 replies posted 10 sign-ins

We are using BTF3125EJXUMA1 part in our design. We need the PCB layout recommendations.  

As per datasheet, Cooling tab is output of low side switch. So we need how to route the this low side switch routing. Please check below layout, what we did is correct?

gunasekart_0-1681139742337.png

gunasekart_1-1681139786427.png

 

 

0 Likes
1 Solution
Neo_Qin
Moderator
Moderator
Moderator
5 likes given 250 replies posted 250 sign-ins

Hi @gunasekart ,

Thank you for considering Infineon for your design collaboration.

According to the information you provided, I believe there are several points that need to be noted:

1) I noticed that Pin4_SRP does not have an electrical connection.  According to Chapter 11.1 of the datasheet , it is recommended not to let the SRP pin floating. A maximum resistor of 200 kOhm to GND is recommended. Assure that the offset between the ground connection of the slew rate resistor and ground pin of the device (GND/SOURCE) is minimized.

2)  The cooling tab, as the Drain of BTF3125EJ, special attention should be paid to parasitic inductance caused by PCB routing.

a. Make traces short and straight through proper layout as much as possible.

b. Couple with plane layers or ground layers to the fullest extent possible, and minimize the area of closed current loops.

c. Stay away from high-frequency control signals as much as possible and avoid parallel traces.

3)   The cooling tab is also the exposed pad /heat slug of the PG-TDSO-8-31 package, together with Pin6~8_GND, are critical to ensuring proper heat dissipation design. More details please refer to the chapter 2 of  Board Assembly Recommendations (Gullwing) 

Kind Regards,

Neo

View solution in original post

0 Likes
1 Reply
Neo_Qin
Moderator
Moderator
Moderator
5 likes given 250 replies posted 250 sign-ins

Hi @gunasekart ,

Thank you for considering Infineon for your design collaboration.

According to the information you provided, I believe there are several points that need to be noted:

1) I noticed that Pin4_SRP does not have an electrical connection.  According to Chapter 11.1 of the datasheet , it is recommended not to let the SRP pin floating. A maximum resistor of 200 kOhm to GND is recommended. Assure that the offset between the ground connection of the slew rate resistor and ground pin of the device (GND/SOURCE) is minimized.

2)  The cooling tab, as the Drain of BTF3125EJ, special attention should be paid to parasitic inductance caused by PCB routing.

a. Make traces short and straight through proper layout as much as possible.

b. Couple with plane layers or ground layers to the fullest extent possible, and minimize the area of closed current loops.

c. Stay away from high-frequency control signals as much as possible and avoid parallel traces.

3)   The cooling tab is also the exposed pad /heat slug of the PG-TDSO-8-31 package, together with Pin6~8_GND, are critical to ensuring proper heat dissipation design. More details please refer to the chapter 2 of  Board Assembly Recommendations (Gullwing) 

Kind Regards,

Neo

0 Likes