SLUU130A – September 2002 – Revised February 2003
14
TPS40003-Based 5-A Converter in Less Than One Square Inch
Figure 9 shows the startup waveforms with an input voltage of 3.3 V and a load of 0.3
Ω
. Note that the output
is held low until V
SS
(pin 4) goes above 0.12 V, and then the output comes up smoothly under closed loop
softstart control.
STARTUP WAVEFORM
t – Time – 200
µ
s/div
1 V/div
500 mV/div
500 mV/div
Figure 9.
Figure 10 shows the transient response for a fast load step from 1 A to 2 A.
TRANSIENT RESPONSE
t – Time – 20
µ
s/div
50 mV/div
Figure 10.