Datasheet

LTC3450
7
3450fa
PI FU CTIO S
UUU
CF1
0.1µF
C1
2.2µF
V
IN
1.5V TO
4.6V
AV
DD
5.1V/10mA
VGH (3 × AV
DD
)
15V/500µA
10V
VGL
10V/500µA
3450 TA01
C1
+
C1
V2X
V
IN
SHDN
GLOBAL SHUTDOWN
MODE
SW V
OUT
OFF ON
BLANK SCAN
L1
47µH
C2
2.2µF
C7
1µF
8
6
4
5
7
9
11
10
12
SHUTDOWN
SYNCHRONOUS
PWM BOOST
CONVERTER
OSCILLATOR
CHARGE PUMP
DOUBLER
IN
OUT
CF2
0.1µF
C2
+
C2
V3X
C8
0.47µF
14
13
15
SHUTDOWN
SHUTDOWN
CHARGE PUMP
TRIPLER
IN
69kHz
550kHz
OUT
CF3
0.1µF
C3
+
C3
V
NEG
GND
C11
0.47µF
1
V
INV
16
2
3
SHUTDOWN
CHARGE PUMP
INVERTER
IN
OUT
BLOCK DIAGRA
W
V3X (Pin 15): Charge Pump Tripler Output. This output is
15.3V (nom) at no load and is capable of delivering up to
500µA to a load. V3X should be bypassed to GND with a
0.1µF X5R type ceramic capacitor.
V
INV
(Pin 16): Positive Voltage Input for the Charge Pump
Inverter. The charge pump inverter will generate a nega-
tive voltage corresponding to the voltage applied to V
INV
.
Connecting V
INV
to 5V or 10V will generate –5V or –10V
respectively on V
NEG
. See Applications section for –15V
generation.
Exposed Pad
(Pin 17): The exposed pad must be con-
nected to V
NEG
(Pin 3) on the PCB.
Do not connect the
exposed pad to GND.