TPS65987EVM: What is the target of this part of circuit?

juanma cc

Part Number: TPS65987EVM

I'm working on a PCB design where I need to add a TPS65987 USB-C controller.

I'm using the TPS65987 EVM schematics to add to my design but there are some circuit parts than I don't understand.

In the next schematic, what is the target of the power MOSFETs confronted between them? What are C32, C33 and R55 for? What is the purpose of the OpAmp U5?

PP_EXT1 goes to a jumper, VBUS comes from VBUS USB-C connector.

PP_EXT2_EN is function as single wire enable signal for external power path 1. Pull-down with external resistor when used for external path control.

over 2 years ago

0 Prajith Cheerakkoda over 2 years ago

TI__Expert 7700 points

Hi,

The back-back FETs are bidirectional switch for external power path.

C33 and R57 control the FET slew rate.

R55 keeps the G and S terminals of FET at same potential when the power path is OFF.

Let me check internally on the need for C32.

Opam is for reverse current protection when the power path is in Sink mode.

Thanks
Prajith

0 juanma cc over 2 years ago in reply to Prajith Cheerakkoda

Prodigy 140 points

Sorry, I have another fast question: Have I understood DNP palces as wired or not wired? I mean, the mosfet gates are connected to VBUS and is the same as PP_EXT1, right?

Thank you so much.

0 Prajith Cheerakkoda over 2 years ago in reply to juanma cc

TI__Expert 7700 points

Hi,

DNP means Do Not Populate (Open circuit - Not wired).

Thanks
Prajith

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TPS65987EVM: What is the target of this part of circuit?