Rainbow Electronics MAX17101 - Manual (Page 11)

MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
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STANDBY AND SHUTDOWN INPUT
SUPPLY CURRENT vs. INPUT VOLTAGE
MAX17101 toc10
INPUT VOLTAGE (V)
SUPPLY CURRENT (mA)
15 20 5 10
0.1
1
0.01
0 25
STANDBY (ONLDO = V IN )
SHUTDOWN
(ONLDO = ON1 = ON2 = GND)
LDO AND RTC POWER-UP
MAX17101 toc11
200 μs/div
A. INPUT SUPPLY, 5V/div
B. 5V LDO, 2V/div
0V
0V
0V
0V
A
12V
B
5V
C
3.3V
D
2.0V
12V
C. 3.3V RTC, 2V/div
D. 2.0V REF, 1V/div
LDO AND RTC POWER REMOVAL
MAX17101 toc12
200 μs/div
A. INPUT SUPPLY, 5V/div
B. 5V LDO, 2V/div
5V
3.3V
2V
A
12V
B
5V
C
3.3V
D
2.0V
12V
C. 3.3V RTC, 2V/div
D. 2.0V REF, 1V/div
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V IN = 12V, V DD = V CC = 5V, TON = REF, T A = +25°C, unless otherwise noted.)
5V LDO LOAD TRANSIENT
MAX17101 toc13
4 μs/div
A. LDO OUTPUT,
100mV/div
5V
0.1A
0A
A
B
B. LOAD CURRENT,
100mA/div
5V SMPS STARTUP AND SHUTDOWN
MAX17101 toc14
200 μs/div
A. 5V LDO OUTPUT, 0.2V/div
B. 5V SMPS OUTPUT, 2V/div
C. ON1, 5V/div
5V
5V
0V
0V
A
5V
B
5V
C
5V
STARTUP WAVEFORMS
(SWITCHING REGULATORS)
MAX17101 toc15
100 μs/div
A. ON1, 2V/div
B. 5V SMPS OUTPUT,
2V/div
5V
5V
0A
0V
0V
0V
A
B
5V
C
D
5V
C. PGOOD1, 5V/div
D. INDUCTOR CURRENT,
5A/div