MAX8643_0709 Datasheet, PDF (5/16 Pages) Maxim Integrated Products – 3A, 2MHz Step-Down Regulator with Integrated Switches

3A, 2MHz Step-Down Regulator
with Integrated Switches
Typical Operating Characteristics (continued)
(Typical values are at V_IN = V_DD = 3.3V, V_OUT = 1.8V, R_FREQ = 50kΩ, I_OUT = 3A, and T_A = +25°C, unless otherwise noted.)
EFFICIENCY vs. OUTPUT CURRENT
100
95
90
85
V_OUT = 1.8V
80
V_OUT = 1.5V
75
70
V_OUT = 1.2V
65 ^VIN ^{= 2.5V}
V_DD = 3.3V
60
0.1
1
10
OUTPUT CURRENT (A)
FREQUENCY vs. INPUT VOLTAGE
1950
1800
1650
1500
1350
1200
1050
900
2.2
-40°C ^{+25°C +85°C}
-40°C
+25°C +85°C
2.6
3.0
3.4
3.8
INPUT VOLTAGE (V)
LOAD REGULATION
0
V_IN = V_DD = 3.3V
-0.02
-0.04
V_OUT = 2.5V
-0.06
-0.08
V_OUT = 1.8V
-0.10
-0.12
-0.14
V_OUT = 1.2V
-0.16
0
1
2
3
4
5
LOAD CURRENT (A)
LOAD TRANSIENT
MAX8643 toc06
V_IN = V_DD = 3.3V
AC-COUPLED
V_OUT
50mV/div
I_OUT
1A/div
0A
40μs/div
SWITCHING WAVEFORMS
MAX8643 toc07
V_OUT
AC-COUPLED
20mV/div
2A/div
I_LX
0A
V_LX
2V/div
0V
100ns/div
SOFT-START WAVEFORMS
MAX8643 toc08
SHUTDOWN WAVEFORMS
MAX8643 toc09
V_EN
2V/div
V_EN
2V/div
0V
0V
V_OUT
1V/div
0V
R_LOAD = 1Ω
400μs/div
V_OUT
1V/div
0V
R_LOAD = 1Ω
10μs/div
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