Rainbow Electronics MAX8621Z - Manual (Page 15)

MAX8621Y/MAX8621Z
Dual Step-Down DC-DC Power-Management ICs
for Portable Devices
______________________________________________________________________________________ 15
UVLO
REF
ON/OFF CONTROL
VOLTAGE
SELECTOR
STEP-DOWN
DC-DC (1, BUCK1)
IN
REF
EN
INP
LX
PGND
FB
STEP-DOWN
DC-DC (2, BUCK2)
IN
REF
EN
INP
LX
PGND
FB
THERMAL
SHUTDOWN
LDO4
OUT
INP
IN
REF
EN
GND
LDO2
OUT
INP
IN
REF
EN
GND
LDO1
OUT
INP
IN
REF
EN
GND
RESET
N
9-BIT SEL
LDO3
OUT
INP
IN
REF
EN
GND 9-BIT SEL
9-BIT SEL
9-BIT SEL
P
N
P
N
IN2 IN3
INPUT
2.6V TO 5.5V
REFBP
GND
DR
ENDR
OUT3
EN3
OUT4
EN4
800k Ω
SEL2
SEL1
EN2
OUT2
FB2
PGND2
LX2
FB1
PGND1
LX1
IN1
RESET
OUT1
R2
115k
Ω
R3
150k Ω
R1
150k Ω
R4
75k
Ω
C6
150pF
PWRON
INPUT
2.6V TO 5.5V
PGND2
BUCK2
IN1
14k Ω
1.3 Ω, 200mA
C3
4.7 µF
C2
4.7
µF
C4
0.01 µF
C11
2.2 µF
C12
2.2 µF
800k Ω
C10
4.7
µF
C7
2.2
µF
C8
150pF C9
2.2
µF
L2
2.2 µH
L1
2.2 µH
C1
10
µF
C5
4.7
µF
BUCK1
MAX8621Y
MAX8621Z
Figure 3. Functional Diagram and Typical Application Schematic