Typical Performance Characteristics (Circuit of Figure 2)
Continuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 1A
Discontinuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 300 mA
L = 47 µH, COUT = 68 µF, COUTESR = 50 mΩ
L = 15 µH, COUT = 68 µF (2x), COUTESR = 25 mΩ
01280318
01280319
A: V
Pin Voltage, 10 V/div.
A: V
Pin Voltage, 10 V/div.
SW
SW
B: Inductor Current, 0.5 A/div
B: Inductor Current, 0.5 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
C: Output Ripple Voltage, 20 mV/div AC-Coupled
Horizontal Time Base: 1 µs/div
Horizontal Time Base: 1 µs/div
Load Transient Response for Continuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 1A
Load Transient Response for Discontinuous Mode
VIN = 20V, VOUT = 5V,
L = 47 µH, COUT = 68 µF, COUTESR = 50 mΩ
L = 47 µH, COUT = 68 µF, COUTESR = 50 mΩ
01280320
01280321
A: Output Voltage, 100 mV/div, AC-Coupled.
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 200 mA to 1A Load Pulse
B: Load Current: 100 mA to 400 mA Load Pulse
Horizontal Time Base: 50 µs/div
Horizontal Time Base: 200 µs/div
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