MAX8571 MAXIM [Maxim Integrated Products], MAX8571 Datasheet - Page 6

• Manufacturer Part Number: MAX8571
• Description: High-Efficiency LCD Boost with True Shutdown
• Manufacturer: MAXIM [Maxim Integrated Products]

High-Efficiency LCD Boost
with True Shutdown
Figure 1. Functional Diagram
Figure 2. Typical Application Circuit with Adjustable Output
Voltage
Figure 4. Using a Separate Input Supply for the Inductor
6
V
V
CC
CC
ON
ON
_______________________________________________________________________________________
= 2.7V TO 5.5V
= 2.7V TO 5.5V
V
BATT
4.7µF
C3
= 0.8V TO 28V
4.7µF
1µF
1µF
OFF
OFF
C1
C3
C1
SW
V
SHDN
SW
V
SHDN
CC
CC
MAX8570
MAX8571
MAX8574
MAX8570
MAX8571
MAX8574
22µH
SHDN
22µH
L1
L1
V
CC
GND
GND
LX
FB
LX
FB
MAX8570–
MAX8575
SHUTDOWN
THERMAL
10pF
10pF
D1
C4
D1
C4
CONTROL
V
V
OUT
LOGIC
OUT
R1
R2
R1
R2
= V
= V
BATT
CC
TO 28V
TO 28V
C2
1µF
C2
1µF
ILIM
EA
Figure 3. Typical Application Circuit with 15V Preset Output
Voltage
Figure 5. Negative Output Voltage for LCD Bias
1.226V
V
CC
ON
= 2.7V TO 5.5V
V
CC
ON
4.7µF
= 2.7V TO 5.5V
1µF
OFF
C3
C1
4.7µF
1µF
OFF
C3
C1
SW
V
SHDN
CC
MAX8570
MAX8571
MAX8574
SW
V
SHDN
22µH
CC
L1
(MAX8572/MAX8573/
MAX8575 ONLY)
SW
LX
OUT
FB
(MAX8570/MAX8571/
MAX8574 ONLY)
GND
MAX8572
MAX8573
MAX8575
GND
22µH
L1
LX
FB
GND
OUT
10pF
LX
D2
C6
0.1µF
D1
C4
D3
D1
R1
V
OUT
C5
1µF
= 15V
C2
1µF
C2
1µF
R2
+V
-V
OUT
OUT