Typical Performance Characteristics
Continuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 2A
Discontinuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 500 mA
L = 32 µH, COUT = 220 µF, COUT ESR = 50 mΩ
L = 10 µH, COUT = 330 µF, COUT ESR = 45 mΩ
01258317
01258318
Horizontal Time Base: 2 µs/div.
Horizontal Time Base: 2 µs/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 1A/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 50 mV/div.
C: Output Ripple Voltage, 100 mV/div.
Load Transient Response for Continuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 500 mA to 2A
L = 32 µH, COUT = 220 µF, COUT ESR = 50 mΩ
Load Transient Response for Discontinuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 500 mA to 2A
L = 10 µH, COUT = 330 µF, COUT ESR = 45 mΩ
01258320
Horizontal Time Base: 200 µs/div.
01258319
A: Output Voltage, 100 mV/div. (AC)
B: 500 mA to 2A Load Pulse
Horizontal Time Base: 100 µs/div.
A: Output Voltage, 100 mV/div. (AC)
B: 500 mA to 2A Load Pulse
Test Circuit and Layout Guidelines
Fixed Output Voltage Versions
01258322
C
C
— 470 µF, 50V, Aluminum Electrolytic Nichicon “PL Series”
— 220 µF, 25V Aluminum Electrolytic, Nichicon “PL Series”
IN
OUT
D1 — 5A, 40V Schottky Rectifier, 1N5825
L1 — 68 µH, L38
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