MAX1556_1 Datasheet, PDF (7/12 Pages) Maxim Integrated Products – 16μA IQ, 1.2A PWM Step-Down DC-DC Converters

16µA I_Q, 1.2A PWM DC-DC
Step-Down Converters
IN
SHDN
SHORT-CIRCUIT
CLOCK
PROTECTION
BIAS
1MHz
CURRENT ^VCS
SENSE
SLOPE
COMP
CURRENT-LIMIT
COMPARATOR
0.675V
PWM
COMPARATOR
PWM
AUTO SKIP
CONTROL
SKIP-OVER
ENTER SKIP/
SR OFF
ZERO-CROSS
DETECT
INP
LX
PGND
ERROR
AMPLIFIER
OUT
REFERENCE
1.25V
Figure 1. Functional Diagram
INPUT
2.6V TO 5.5V
R1
C1
100Ω
10µF
C4
0.47µF
VOLTAGE
SELECT
ON
OFF
INP
LX
MAX1556
IN
PGND
D1
OUT
D2
SS
SHDN
GND
L1
3.3µH
OUTPUT
0.75V TO V_IN
1.2A
C2
22µF
C3
1000pF
GND
OUTPUT
D1
VOLTAGE
SELECTOR
D2
MAX1556
MAX1557
SS
INPUT
2.6V TO 5.5V
C4
10µF
VOLTAGE
SELECT
ON
OFF
INP
LX
MAX1557
PGND
IN
D1
OUT
D2
SS
SHDN
GND
L2
4.7µH
OUTPUT
0.75V TO V_IN
600mA
C5
22µF
C6
1000pF
Figure 2. MAX1556 Typical Application Circuit
Figure 3. MAX1557 Typical Application Circuit
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