LM2674
Typical Performance
Characteristics
(Circuit of
Continuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 500 mA
L = 100 µH, C
OUT
= 100 µF, C
OUT
ESR = 0.1Ω
Discontinuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 300 mA
L = 15 µH, C
OUT
= 68 µF (2x), C
OUT
ESR = 25 mΩ
10004118
10004119
A: V
SW
Pin Voltage, 10 V/div.
B: Inductor Current, 0.2 A/div
C: Output Ripple Voltage, 50 mV/div AC-Coupled
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,
L = 100 µH, C
OUT
= 100 µF, C
OUT
ESR = 0.1Ω
Horizontal Time Base: 1 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
10004120
10004121
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 100 mA to 500 mA Load Pulse
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 100 mA to 400 mA Load Pulse
Horizontal Time Base: 50 µs/div
Horizontal Time Base: 200 µs/div
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