Rainbow Electronics MAX8575 - Manual (Page 6)

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