Typical Performance Characteristics (Circuit of Figure 1)
Continuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 1A
L = 68 µH, COUT = 120 µF, COUT ESR = 100 mΩ
Discontinuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 600 mA
L = 22 µH, COUT = 220 µF, COUT ESR = 50 mΩ
DS012593-18
DS012593-19
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 50 mV/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 50 mV/div.
Horizontal Time Base: 2 µs/div.
Horizontal Time Base: 2 µs/div.
Load Transient Response for Continuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 250 mA to 750 mA
L = 68 µH, COUT = 120 µF, COUT ESR = 100 mΩ
Load Transient Response for Discontinuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 250 mA to 750 mA
L = 22 µH, COUT = 220 µF, COUT ESR = 50 mΩ
DS012593-20
DS012593-21
A: Output Voltage, 100 mV/div. (AC)
B: 250 mA to 750 mA Load Pulse
A: Output Voltage, 100 mV/div. (AC)
B: 250 mA to 750 mA Load Pulse
Horizontal Time Base: 100 µs/div.
Horizontal Time Base: 200 µs/div.
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