Typical Performance Characteristics
Feedback Pin
Bias Current
(Circuit of
Figure 1)
(Continued)
DS012565-10
Continuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 1A
L = 68 µH, C
OUT
= 120 µF, C
OUT
ESR = 100 mΩ
Discontinuous Mode Switching Waveforms
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 600 mA
L = 22 µH, C
OUT
= 220 µF, C
OUT
ESR = 50 mΩ
DS012565-17
DS012565-18
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 50 mV/div.
A: Output Pin Voltage, 10V/div.
B: Inductor Current 0.5A/div.
C: Output Ripple Voltage, 50 mV/div.
Horizontal Time Base: 2 µs/div.
Horizontal Time Base: 2 µs/div.
Load Transient Response for Continuous Mode
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 250 mA to 750 mA
L = 68 µH, C
OUT
= 120 µF, C
OUT
ESR = 100 mΩ
Load Transient Response for Discontinuous Mode
V
IN
= 20V, V
OUT
= 5V, I
LOAD
= 250 mA to 750 mA
L = 22 µH, C
OUT
= 220 µF, C
OUT
ESR = 50 mΩ
DS012565-19
DS012565-20
A: Output Voltage, 100 mV/div. (AC)
B: 250 mA to 750 mA Load Pulse
A: Output Voltage, 100 mV/div. (AC)
B: 250 mA to 750 mA Load Pulse
Horizontal Time Base: 100 µs/div.
Horizontal Time Base: 200 µs/div.
7
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