Datasheet

Input/Output Connections
2-2
2.1 Input/Output Connections
The TPS54x80EVM-228 has the following input/output connections: 5-V
input, 5-V input return, 3.3-V output, 3.3-V output return, 1.8-V output and
1.8-V output return. A diagram showing the connection points is shown in
Figure 2-1. A power supply capable of supplying 15 A should be connected
to J1 through a pair of 16 AWG wires. The 3.3-V and 1.8-V loads should be
connected respectively to J2 and J3 through pairs of 16 AWG wires. The
maximum load current may be reduced from 8 A to 6 A, if the 6-A version of
the TPS54x80EVM-228 with TPS54680/TPS54610 regulators is used. Wire
lengths should be minimized to reduce losses in the wires. Test points TP10
and TP11 provide a place to easily connect an oscilloscope voltage probe to
monitor the output voltages, while TP4 provides a test point for monitoring the
input voltage. The TPS54x80 device is intended to be used as a point of load
regulator typically located close to the input voltage source. When using the
TPS54x80EVM-228 with an external laboratory power supply as the source
for Vin, an additional bulk capacitor may be required, depending upon the
output impedance of the source and length of the hookup wires. The presented
test results were obtained using a 470 µF, 16 V additional input capacitor.
IMPORTANT NOTICE:
The two-channel TPS54x80EVM-228 EVM requires an input voltage of
4.5-V to 6-V to provide 3.3-V output from the TPS54610/TPS54810
regulators for I/O voltage. Stand-alone measurements of TPS54680
regulator operating at a 3.3-V input voltage are also provided for reference.
The TPS54680 has a rated input voltage range of 3.0 to 6.0 V, and may be
powered from a 3.3-V bus in some applications.