[Tested] TPS53355 30A DC-DC step-down module

(The usability of this solution has been successfully verified by soldering.)
Tips: Friends who need higher current and continuous operation under full load can pay attention to its next-generation engineering [tested] 12V input 45A output DC-DC step-down module.
 
2024/2/27 Update Notes:
Improved loop stability under high load.
This change is significant and requires re-boarding!
 
2024/2/9 Update Notes :
After testing, under continuous high load conditions, it is best to add heat dissipation to the inductor as well (for cost considerations, aluminum is sufficient).
 
Design Purpose:
This design is a forward-looking research project on DC-ATX power conversion system design, aiming to ultimately get rid of dependence on commercially available salvaged power modules and achieve a completely independent, highly integrated single-board DC-ATX power adapter board.
 
Design Concept:
After comparing various options, this design ultimately selected Texas Instruments' integrated NextFET power technology MOSFET DC-DC converter chip, TPS53355, detailed below.
Through simulation and gradual optimization of the feedback response loop and inductor selection, the final module's
PCB adopts a four-layer design, including a complete ground plane and power plane, multi-layer current carrying capacity, and open soldering on the critical path of the bottom layer to maximize the PCB's current carrying capacity (those with extra power supplies can modify it to a six-layer board to further improve the current carrying capacity (just kidding)).
 
Simulation Verification:
Simulation verification uses the same component parameters as the schematic diagram of this design. The
efficiency curve is as follows (average up to 97%).
Ripple simulation is as follows (full load ripple can be less than 10mV without an additional output capacitor, optimal 5mV).
 
Other Notes:
Because I had a lot of XT60 connectors and cables on hand, I used the XT60 kit. Other interfaces or connection methods can be modified as needed
. Based on the simulation results, if you want to operate at a full load of 30A for a long time—add heatsink! Add heatsink! Add heatsink!
Although overvoltage protection diodes have been designed, due to cost considerations, an additional VBUS switch was not included. Do not plug it in backwards! Plugting the 12V into VOUT will light up one chip and several diodes!
 
The last picture shows the bottom
 
after adding heat dissipation
; it features an aluminum nitride ceramic plate, which has thermal conductivity exceeding that of aluminum and insulation properties comparable to ceramics.