5V, Step-Down,
Current-Mode PWM DC-DC Converters
MAX730A/MAX738A/MAX744A
____________________________Typical Operating Characteristics (continued)
(Circuit of Figure 3, T
A
= +25°C, unless otherwise noted.)
MAX738A/MAX744A
SWITCHING WAVEFORMS,
CONTINUOUS CONDITION
MAX738A/MAX744A
SWITCHING WAVEFORMS,
DISCONTINUOUS CONDITION
12V
A
0V
200mA
0mA
C
2µs/div
A: SWITCH VOLTAGE (LX PIN), 5V/div, 0V TO +12V
B: INDUCTOR CURRENT, 200mA/div
C: OUTPUT VOLTAGE RIPPLE, 50mV/div, AC-COUPLED
COUT = 390µF,
V+ = 12V, IOUT = 150µA,
2µs/div
A: SWITCH VOLTAGE (LX PIN), 5V/div, 0V TO +12V
B: INDUCTOR CURRENT, 200mA/div
C: OUTPUT VOLTAGE RIPPLE, 50mV/div, AC-COUPLED
COUT = 390µF,
V+ = 12V, IOUT = 150µA
B
12V
A
0V
200mA
0mA
B
C
MAX730A LINE-TRANSIENT RESPONSE
MAX738A/MAX744A LINE-TRANSIENT RESPONSE
A
A
16V
B
11V
B
6V
0V
100ms/div
A: VOUT, 50mV/div, DC-COUPLED
B: V+, 5V/div, 10.2V TO 16.0V
IOUT = 750mA
0V
10.2V
100ms/div
A: VOUT, 50mV/div, DC-COUPLED
B: V+, 5V/div, 6.0V TO 11.0V
IOUT = 300mA
6
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
