Datasheet

Vin=100mV/div(accoupled)
PH=2V/div
Time=500nsec/div
Vin=5V/div
Vout=2V/div
EN=2V/div
PWRGD=5V/div
Time=5msec/div
Test Setup and Results www.ti.com
2.8 Input Voltage Ripple
The TPS54319EVM-626 input voltage ripple is shown in Figure 8 . The output current is the rated full load
of 3 A and V
IN
= 5 V. The ripple voltage is measured directly across the input capacitors.
Figure 8. TPS54319EVM-626 Input Ripple
2.9 Powering Up
2.9.1 Power Up Relative to V
IN
The start-up waveform shown in Figure 9 shows start-up is relative to VIN rising. The input voltage is
initially applied, and when the input reaches the undervoltage lockout threshold, the start-up sequence
begins and the output ramps up at the externally set rate toward the set value of 1.8 V. The input voltage
for this plot is 5 V with a 2 Ω load.
Figure 9. TPS54319EVM-626 Start-Up Relative to V
IN
8
TPS54319EVM-626 3-A, SWIFT™ Regulator Evaluation Module SLVU377–May 2010
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