High-Efficiency, PWM, Step-Down,
N-Channel DC-DC Controller
____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 1a, TA = +25°C, unless otherwise noted.)
LOAD-TRANSIENT RESPONSE
A
B
LOAD-TRANSIENT RESPONSE
A
B
LINE-TRANSIENT RESPONSE
10V
8V
A
B
200µs/div
A: LOAD CURRENT, 0.1A TO 1.5A, 1A/div
B: VOUT RIPPLE, 50mV/div, AC-COUPLED
V+ = 10V
CONTINUOUS-CONDUCTION MODE
WAVEFORMS
A
B
0V
C
5µs/div
A : EXT VOLTAGE, 20V/div
B : INDUCTOR CURRENT 1A/div
C : VOUT RIPPLE, 50mV/div
V+ = 10V, IOUT = 3A
1ms/div
A: LOAD CURRENT, 0.1A TO 1.5A, 1A/div
B: VOUT RIPPLE, 50mV/div, AC COUPLED
V+ = 10V
DISCONTINUOUS-CONDUCTION
IDLE-MODE WAVEFORMS
A
B
C
20µs/div
A: EXT VOLTAGE, 10V/div
B: INDUCTOR CURRENT, 500mA/div
C: VOUT RIPPLE, 50mV/div, AC-COUPLED
V+ = 10V, IOUT = 75mA
500ms/div
A: V+ = 8V TO 10V, 2V/div
B: VOUT RIPPLE, 100mV/div
IOUT = 3A
MODERATE-LOAD, IDLE-MODE
WAVEFORMS
A
B
C
20µs/div
A: EXT VOLTAGE, 10V/div
B: INDUCTOR CURRENT, 500mA/div
C: VOUT RIPPLE, 50mV/div, AC-COUPLED
V+ = 6V, IOUT = 480mA
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