
Typical Performance Characteristics
Continuous Mode Switching Waveforms
V
IN = 20V, VOUT = 5V, ILOAD =2A
L = 32 H, C
OUT = 220 F, COUT ESR=50 m
Discontinuous Mode Switching Waveforms
V
IN = 20V, VOUT = 5V, ILOAD = 500 mA
L = 10 H, C
OUT = 330 F, COUT ESR=45 m
01258317
Horizontal Time Base: 2 s/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 1A/div.
C: Output Ripple Voltage, 50 mV/div.
01258318
Horizontal Time Base: 2 s/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 100 mV/div.
Load Transient Response for Continuous Mode
V
IN = 20V, VOUT = 5V, ILOAD = 500 mA to 2A
L = 32 H, C
OUT = 220 F, COUT ESR=50 m
Load Transient Response for Discontinuous Mode
V
IN = 20V, VOUT = 5V, ILOAD = 500 mA to 2A
L = 10 H, C
OUT = 330 F, COUT ESR=45 m
01258319
Horizontal Time Base: 100 s/div.
A: Output Voltage, 100 mV/div. (AC)
B: 500 mA to 2A Load Pulse
01258320
Horizontal Time Base: 200 s/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
CIN
— 470 F, 50V, Aluminum Electrolytic Nichicon “PL Series”
COUT
— 220 F, 25V Aluminum Electrolytic, Nichicon “PL Series”
D1
— 5A, 40V Schottky Rectifier, 1N5825
L1
— 68 H, L38
LM2596
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