MAX1644EAE-T Datasheet, PDF (4/11 Pages) Maxim Integrated Products – 2A, Low-Voltage, Step-Down Regulator with Synchronous Rectification and Internal Switches

2A, Low-Voltage, Step-Down Regulator with
Synchronous Rectification and Internal Switches
(Circuit of Figure 1, T_A = +25°C, unless otherwise noted.)
Typical Operating Characteristics
EFFICIENCY vs. OUTPUT CURRENT
100
90
80
V_IN = 5V, V_OUT = 3.3V,
70
L = 6.0μH, R_TOFF = 120kΩ
60
50
40
30
20
10
0
0.001
0.01
0.1
1
10
OUTPUT CURRENT (A)
EFFICIENCY vs. OUTPUT CURRENT
100
90
80
70
60
V_IN = 5V, V_OUT = 1.5V,
L = 6.0μH, R_TOFF = 270kΩ
50
40 _{VIN = 3.3V, VOUT = 1.5V,}
30 ^{L = 4.7μH, RTOFF = 200kΩ}
20
10
0
0.001
0.01
0.1
1
10
OUTPUT CURRENT (A)
350
300
250
200
150
100
50
0
0
SWITCHING FREQUENCY
vs. OUTPUT CURRENT
V_IN = 5V,
V_OUT = 3.3V,
L = 6.0μH,
R_TOFF = 120kΩ
V_IN = 3.3V,
V_OUT = 1.5V,
V_IN = 5V,
L = 4.7μH,
V_OUT = 1.5V, ^RTOFF ^{= 200kΩ}
L = 6.0μH,
R_TOFF = 270kΩ
0.5
1.0
1.5
2.0
OUTPUT CURRENT (A)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
500
MAX1644-07 _0.10
450 ^IOUT ^{= 0}
0.09
400
0.08
350
0.07
300
SHDN = V_IN = V_CC
0.06
250
0.05
200 _UNDERVOLTAGE
0.04
150 LOCKOUT
0.03
100
SHDN = GND
0.02
50
0.01
0
0
0123456
SUPPLY VOLTAGE
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
0
V_SHDN
5V/div
0
I_IN
1A/div
0
V_OUT
2V/div
0
OFF-TIME vs. R_TOFF
100 200 300 400 500 600
R_TOFF (kΩ)
STARTUP AND
SHUTDOWN TRANSIENTS
V_SS
1V/div
0
V_IN = 5.0V, V_OUT = 3.3V, I_OUT = 2A
2ms/div
DC LOAD-REGULATION ERROR
vs. OUTPUT CURRENT
0
-0.1
AB
-0.2
-0.3
D
-0.4
E
C
-0.5
-0.6
-0.7
-0.8
-0.9
-1.0
0.0001 0.001 0.01 0.1
1
10
OUTPUT CURRENT (A)
A: V_IN = 3.3V, V_OUT = 1.5V, L = 4.7μH,
R_TOFF = 200kΩ, FBSEL = GND
B: V_IN = 3.3V, V_OUT = 1.5V, L = 4.7μH,
R_TOFF = 200kΩ, FBSEL = REF
C: V_IN = 5V, V_OUT = 3.3V, L = 6.0μH,
R_TOFF = 120kΩ, FBSEL = OPEN
D: V_IN = 5V, V_OUT = 1.5V, L = 6.0μH,
R_TOFF = 270kΩ, FBSEL = GND
E: V_IN = 5V, V_OUT = 1.5V, L = 6.0μH,
R_TOFF = 270kΩ, FBSEL = REF
4 _______________________________________________________________________________________