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Powering Up and Down
2-10
2.10 Powering Up and Down
The start-up voltage waveform of the TPS54350EVM−235 is shown in
Figure 2−12. The waveform shows the nominal 12-V input voltage in Ch. 1, the
3.3-V output ramping up in Ch. 2 and the PWRGD signal in Ch. 3. Note that
the PWRGD signal is pulled up externally to 3.3 V.
Figure 2−12. Powering Up
VI 5 V/div
Vpwrgd 2 V/div
t − Time − 2 ms/div
VO 2 V/div
The corresponding power down waveform is shown in Figure 2−13 The
channel assignments are the same as in the power up waveform above.
Figure 2−13. Powering Down
VI 5 V/div
Vpwrgd 2 V/div
t − Time − 2 ms/div
VO 2 V/div