Datasheet

Typical Performance Characteristics (Circuit of Figure 2)
Continuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 1A
L = 47 μH, C
OUT
= 68 μF, C
OUT
ESR = 50 mΩ
1293418
A: V
SW
Pin Voltage, 10 V/div.
B: Inductor Current, 0.5 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
Horizontal Time Base: 1 μs/div
Discontinuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 300 mA
L = 15 μH, C
OUT
= 68 μF (2×), C
OUT
ESR = 25 mΩ
1293419
A: V
SW
Pin Voltage, 10 V/div.
B: Inductor Current, 0.5 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
Horizontal Time Base: 1 μs/div
Load Transient Response for Continuous Mode
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 1A
L = 47 μH, C
OUT
= 68 μF, C
OUT
ESR = 50 mΩ
1293420
A: Output Voltage, 100 mV/div, AC-Coupled
B: Load Current: 200 mA to 1A Load Pulse
Horizontal Time Base: 50 μs/div
Load Transient Response for Discontinuous Mode
V
IN
= 20V, V
OUT
= 5V,
L = 47 μH, C
OUT
= 68 μF, C
OUT
ESR = 50 mΩ
1293421
A: Output Voltage, 100 mV/div, AC-Coupled
B: Load Current: 100 mA to 300 mA Load Pulse
Horizontal Time Base: 200 μs/div
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LM2672