LM2678
Typical Performance Characteristics
Continuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 5A
L = 10 µH, C
OUT
= 400 µF, C
OUT
ESR = 13 mΩ
Discontinuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 500 mA
L = 10 µH, C
OUT
= 400 µF, C
OUT
ESR = 13 mΩ
DS100886-17
DS100886-18
A: V
SW
Pin Voltage, 10 V/div.
B: Inductor Current, 2 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
A: V
SW
Pin Voltage, 10 V/div.
B: Inductor Current, 1 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 = 10 µH, C
OUT
= 400 µF, C
OUT
ESR = 13 mΩ
Horizontal Time Base: 1 µs//iv
Load Transient Response for Discontinuous Mode
V
IN
= 20V, V
OUT
= 5V,
L = 10 µH, C
OUT
= 400 µF, C
OUT
ESR = 13 mΩ
DS100886-19
DS100886-20
A: Output Voltage, 100 mV//div, AC-Coupled.
B: Load Current: 500 mA to 5A Load Pulse
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 200 mA to 3A Load Pulse
Horizontal Time Base: 100 µs/div
Horizontal Time Base: 200 µs/div
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