Datasheet

Data Sheet ADP1870/ADP1871
Rev. B | Page 15 of 44
CH1 10A Ω CH2 200mV
B
W
CH3 20V CH4 5V
M10µs A CH1 5.60A
T 23.8%
1
2
3
4
OUTPUT VOLTAGE
12A NEGATIVE STEP
SW NODE
LOW
SIDE
08730-051
Figure 52. Negative Step During Heavy Load Transient Behavior—Forced PWM
at Light Load, 12 A (See Figure 94 Application Circuit)
CH1 2V
B
W
CH2 5A Ω
CH3 10V CH4 5V
M4ms A CH1 920mV
T 49.4%
1
2
3
4
OUTPUT VOLTAGE
INDUCTOR CURRENT
SW NODE
LOW SIDE
08730-052
Figure 53. Output Short-Circuit Behavior Leading to Hiccup Mode
CH1 5V
B
W
CH2 10A Ω
CH3 10V CH4 5V
M10µs A CH2 8.20A
T
36.2%
1
2
3
4
OUTPUT VOLTAGE
INDUCTOR CURRENT
SW NODE
LOW SIDE
08730-053
Figure 54. Magnified Waveform During Hiccup Mode
CH1 2V
B
W
CH2 5A Ω
CH3 10V CH4 5V
M2ms A CH1 720mV
T 32.8%
1
2
3
4
OUTPUT VOLTAGE
INDUCTOR CURRENT
SW NODE
LOW SIDE
08730-054
Figure 55. Start-Up Behavior at Heavy Load, 12 A, 300 kHz
(See Figure 94 Application Circuit)
CH1 2V
B
W
CH2 5A Ω
CH3 10V CH4 5V
M4ms A CH1 720mV
T 41.6%
1
2
3
4
OUTPUT VOLTAGE
INDUCTOR CURRENT
SW NODE
LOW SIDE
08730-055
Figure 56. Power-Down Waveform During Heavy Load
CH1 50mV
B
W
CH2 5A Ω
CH3 10V
B
W
CH4 5V
M2µs A CH2 3.90A
T 35.8%
1
2
3
4
OUTPUT VOLTAGE
INDUCTOR CURRENT
SW NODE
LOW SIDE
08730-056
Figure 57. Output Voltage Ripple Waveform During PSM Operation
at Light Load, 2 A