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2.1.6
JP2 –SYNC/PS
2.2
Setup
2.3
Power Up
EN Pin
VOUT 1V/div
2.4
Output Ripple
Setup and Results
Center pin is SYNC input, and is used to synchronize the unit with an external clock. Also, in power-saving
mode, 1=disabled and 0=enabled. Shorting jumper JP2 between the center pin and VIN disables
power-saving mode; jumper between center pin and GND enables power-saving mode.
To operate the EVM, simply connect an input supply to the appropriate pins, connect a load to the
appropriate pins. Maximum recommended load is 600 mA or 5.5
Ω
. Input supply voltage of 3.0 V to 5.5 V
is recommended.
The soft-start circuit is controlled by a ramp to the current limit comparator that starts the switch current
limit low and increases it to 1.7 A. Output voltage is monitored during this time and must increase for
switch current to increase.
Figure 1. Turn ON into Electronic Load
Output ripple occurs at the switching frequency of 1 MHz, and with the recommended L and output C, is
low. Amplitude of the ripple varies, depending on load current and input voltage. Ensure the oscilloscope
probe is connected as close as possible to the output capacitor, with a very short ground lead, for
accurate measurements. Resistance in trace and leads adds to output ripple, and ground lead length
increases the amplitude of switching spikes.
SLVU156 – March 2006
TPS63000EVM-148
3