Typical Performance Characteristics
Continuous Mode Switching Waveforms
Discontinuous Mode Switching Waveforms
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=
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VIN 20V, VOUT 5V, ILOAD 400 mA
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=
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VIN 20V, VOUT 5V, ILOAD 200 mA
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= =
100 µH, COUT 120 µF, COUT ESR 140 mΩ
L
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= =
33 µH, COUT 220 µF, COUT ESR 60 mΩ
L
DS012439-17
DS012439-18
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.2A/div.
C: Output Ripple Voltage, 20 mV/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.2A/div.
C: Output Ripple Voltage, 20 mV/div.
Horizontal Time Base: 2 µs/div.
Horizontal Time Base: 2 µs/div.
Load Transient Response for Continuous Mode
Load Transient Response for Discontinuous Mode
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VIN 20V, VOUT 5V, ILOAD 200 mA to 500 mA
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=
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VIN 20V, VOUT 5V, ILOAD 100 mA to 200 mA
=
= =
100 µH, COUT 120 µF, COUT ESR 140 mΩ
L
=
= =
33 µH, COUT 220 µF, COUT ESR 60 mΩ
L
DS012439-20
DS012439-19
A: Output Voltage, 50 mV/div. (AC)
B: 100 mA to 200 mA Load Pulse
A: Output Voltage, 50 mV/div. (AC)
B: 200 mA to 500 mA Load Pulse
Horizontal Time Base: 200 µs/div.
Horizontal Time Base: 50 µs/div.
7
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