MAX1684 Datasheet, PDF (6/16 Pages) Maxim Integrated Products – Low-Noise, 14V Input, 1A, PWM Step-Down Converters

Low-Noise, 14V Input, 1A, PWM
Step-Down Converters
Typical Operating Characteristics (continued)
(Circuit of Figure 1, T_A = +25°C, unless otherwise noted.)
MAXIMUM LOAD CURRENT
vs. INPUT VOLTAGE
1.8
1.7
1.6
1.5
1.4
SAFE OPERATING AREA
1,400
1,200
V_OUT = 3.3V
1,000
800
600
DROPOUT VOLTAGE vs. LOAD CURRENT
400
300
V_OUT = 3.3V
200
1.3
400
V_OUT = 5V
1.2
1.1
PWM OR NORMAL MODE
1.0
02468
10 12 14
INPUT VOLTAGE (V)
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE (V_OUT = 3.3V)
300
SCHOTTKY LEAKAGE
250
CURRENT INCLUDED
200
150
100
NORMAL MODE
50
LOW-POWER MODE
0
4 5 6 7 8 9 10 11 12 13 14 15
INPUT VOLTAGE (V)
200
0
0 2 4 6 8 10 12 14 16
INPUT VOLTAGE (V)
MAX1684
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
(V_OUT = 3.3V, PWM MODE)
5.0
4.5
4.0
3.5
3.0
2.5
2.0
4 5 6 7 8 9 10 11 12
INPUT VOLTAGE (V)
100
0
0
INDUCTOR RESISTANCE INCLUDED
200 400 600 800
LOAD CURRENT (mA)
1,000
15
14
13
12
11
10
9
8
7
6
2.7
0
PWM FIXED-FREQUENCY
OPERATION AREA
MAX1684
MAX1685
2 4 6 8 10 12 14
OUTPUT VOLTAGE (V)
LOAD-TRANSIENT RESPONSE
MAX1684/85-16
SWITCHING WAVEFORM
MAX1684/85-17
SWITCHING WAVEFORM
MAX1684/85-18
I_LOAD
500mA/div
V_OUT
20mV/div
V_LX
5V/div
V_OUT
50mV/div
I_LX
100mA/div
I_LX
100mA/div
2ms/div
MAX1684, I_LOAD = 0.1mA TO 1A, V_OUT = 3.3V, V_IN = 5V,
SYNC/PWM = 3.3V
1µs/div
MAX1684, I_LOAD = 100mA, V_OUT = 3.3V, V_IN = 5V,
SYNC/PWM = 3.3V
1µs/div
MAX1684, I_LOAD = 100mA, V_OUT = 3.3V, V_IN = 5V,
SYNC/PWM = 3.3V
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