LT3463/LT3463A
Dual Micropower
DC/DC Converters
with Schottky Diodes
FEATURES
s
s
DESCRIPTIO
s
s
s
s
s
s
Generates Well-Regulated Positive and
Negative Outputs
Low Quiescent Current:
20
µ
A (per Converter) in Active Mode
<1
µ
A in Shutdown Mode
Internal 42V Power Switches
Internal 42V Schottky Diodes
Low V
CESAT
Switch: 180mV at 150mA
Input Voltage Range: 2.4V to 15V
High Output Voltages: Up to
±40V
Low Profile (0.8mm) 3mm x 3mm DFN Package
APPLICATIO S
s
s
s
s
CCD Bias
LCD Bias
Handheld Computers
Digital Cameras
The LT
®
3463/LT3463A are dual micropower DC/DC con-
verters with internal Schottky diodes in a 10-lead 3mm
×
3mm DFN package. Negative and positive LT3463 con-
verters have a 250mA current limit. The LT3463A positive
converter also has a 250mA limit, while the negative
converter has a 400mA limit. Both devices have an input
voltage range of 2.4V to 15V, making them ideal for a wide
variety of applications. Each converter features a quies-
cent current of only 20µA, which drops to under 1µA in
shutdown. A current limited, fixed off-time control scheme
conserves operating current, resulting in high efficiency
over a broad range of load current. The 42V switch enables
high voltage outputs up to
±40V
to be easily generated
without the use of costly transformers. The low 300ns off-
time permits the use of tiny, low profile inductors and
capacitors to minimize footprint and cost in space-con-
scious portable applications.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
V
IN
2.7V
TO 5V
4.7µF
V
IN
SHDN1
LT3463A
SHDN2
GND
SW2
SW1 V
OUT1
FB1
V
REF
FB2
D2
10µH
CCD Bias Supply (15V, –8V)
V
OUT1
15V
10mA
2.2µF
EFFICIENCY (%)
Efficiency and Power Loss
80
15V EFFICIENCY
75
70
65
60
15V LOSS
55
40
–8V LOSS
0
100
3463 TA01b
1M
90.9k
154k
10µH
1µF
1M
10pF
V
OUT2
–8V
50mA
3463 TA01a
50
0.1
1
10
LOAD CURRENT (mA)
4.7µF
U
V
IN
= 3.6V
240
200
POWER LOSS (mW)
U
U
–8V EFFICIENCY
160
120
80
3463f
1
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
