MAX1533A Datasheet, PDF (10/38 Pages) Maxim Integrated Products – High-Efficiency, 5x Output, Main Power-Supply Controllers for Notebook Computers

High-Efficiency, 5x Output, Main Power-Supply
Controllers for Notebook Computers
Typical Operating Characteristics (continued)
(MAX1537A circuit of Figure 1, V_IN = 12V, LDO5 = V_CC = 5V, SKIP = GND, FSEL = REF, T_A = +25°C, unless otherwise noted.)
IDLE-MODE CURRENT
vs. INPUT VOLTAGE
3.5
DUTY CYCLE
3.0
LIMITED
2.5
2.0
1.5
1.0
0.5
0
0
5V OUTPUT
5 10 15 20 25 30
INPUT VOLTAGE (V)
AUXILIARY LINEAR-REGULATOR
LOAD REGULATION
12.1
12.0
11.9
11.8
11.7
0
40
80 120 160 200
LDOA LOAD CURRENT (mA)
LINEAR-REGULATOR
2.0V REFERENCE LOAD REGULATION
LOAD REGULATION
2.02
50
2.01
2.00
1.99
1.98
-20
0 20 40 60 80 100
REF LOAD CURRENT (μA)
INTERLEAVED OPERATION
MAX1533/37 toc14
12V
A
0
5V
B
0
C
12V
D
0
3.3V
E
0
F
2.0μs/div
A. LX5, 10V/div
B. 5V OUTPUT, 100mV/div
C. PWM5 INDUCTOR CURRENT, 5A/div
D. LX3, 10V/div
E. 3.3V OUTPUT, 100mV/div
F. PWM3 INDUCTOR CURRENT, 5A/div
0
LDO3
LDO5
-50
-100
-150
-200
0
V_IN = 6V
ON3 = ON5 = GND
20 40 60 80 100 120 140
LDO LOAD CURRENT (mA)
LINEAR-REGULATOR
STARTUP WAVEFORMS
MAX1533/37 toc15
5V
A
0
4V
B
2V
0
2V
C
0
2V
D
0
400μs/div
A. SHDN, 5V/div
B. LDO5, 2V/div
C. LDO3, 2V/div
D. REF, 2V/div
100Ω LOAD ON LDO5 AND LDO3
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