A good PCB layout for the TPS51621RHAT involves placing the input capacitors close to the VIN pin, using a solid ground plane, and keeping the high-current paths short and wide. It's also recommended to use a 4-layer PCB with a dedicated power plane and a dedicated ground plane.
To ensure the stability of the output voltage, it's essential to choose the right output capacitor value and type. A minimum capacitance of 10uF is recommended, and the capacitor should have a low ESR (Equivalent Series Resistance) to minimize voltage ripple. Additionally, the output voltage can be stabilized by adding a small ceramic capacitor (e.g., 100nF) in parallel with the output capacitor.
The TPS51621RHAT is rated for operation from -40°C to 125°C, but the maximum ambient temperature range depends on the specific application and the power dissipation of the device. It's essential to ensure that the device does not exceed the maximum junction temperature (TJ) of 150°C.
The power dissipation of the TPS51621RHAT can be calculated using the following formula: Pd = (VIN x IIN) - (VOUT x IOUT), where Pd is the power dissipation, VIN is the input voltage, IIN is the input current, VOUT is the output voltage, and IOUT is the output current. The calculated power dissipation should be within the maximum power dissipation rating of the device.
The recommended input capacitor value for the TPS51621RHAT is 10uF to 22uF, with a voltage rating of at least 1.5 times the maximum input voltage. The input capacitor should have a low ESR and be placed close to the VIN pin to minimize voltage ripple and ensure stable operation.
TPS51621RHAT datasheet
by Texas Instruments
