SBVS128F June 2009 – December 2015 TPS727
To improve ac performance (such as PSRR, output noise, and transient response), TI recommends that the board be designed with separate ground planes for VIN and VOUT, with the ground plane connected only at the GND pin of the device. In addition, the ground connection for the output capacitor must be connected directly to the GND pin of the device. High ESR capacitors may degrade PSRR.
The ability to remove heat from the die is different for each package type, presenting different considerations in the printed circuit board (PCB) layout. The PCB area around the device that is free of other components moves the heat from the device to the ambient air. Performance data for JEDEC low- and high-K boards are given in the Thermal Information table. Using heavier copper increases the effectiveness in removing heat from the device. The addition of plated through-holes to heat-dissipating layers also improves the heatsink effectiveness.
Power dissipation depends on input voltage and load conditions. Power dissipation (PD) is equal to the product of the output current times the voltage drop across the output pass element (VIN to VOUT), as shown in Equation 3:
This section provides the TPS727xxDSEEVM-406 board layout and illustrations.
This section provides the TPS727xxYFFEVM-407 board layout and illustrations.