LT3463_15 Datasheet, PDF (1/8 Pages) Linear Technology – Dual Micropower DC/DC Converters with Schottky Diodes

FEATURES
s _{Generates Well-Regulated Positive and}
Negative Outputs
s _{Low Quiescent Current:}
20µA (per Converter) in Active Mode
<1µA in Shutdown Mode
s _{Internal 42V Power Switches}
s _{Internal 42V Schottky Diodes}
s _{Low VCESAT Switch: 180mV at 150mA}
s _{Input Voltage Range: 2.4V to 15V}
s _{High Output Voltages: Up to ±40V}
s _{Low Profile (0.8mm) 3mm x 3mm DFN Package}
U
APPLICATIO S
s _{CCD Bias}
s _{LCD Bias}
s _{Handheld Computers}
s _{Digital Cameras}
LT3463/LT3463A
Dual Micropower
DC/DC Converters
with Schottky Diodes
DESCRIPTIO
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
CCD Bias Supply (15V, –8V)
10µH
V_IN
SW1 V_OUT1
SHDN1
FB1
LT3463A _VREF
SHDN2
FB2
GND SW2
D2
1M
90.9k
154k
V_OUT1
15V
10mA
2.2µF
10µH
1µF
1M
4.7µF
10pF
V_OUT2
–8V
50mA
3463 TA01a
Efficiency and Power Loss
80
15V EFFICIENCY
75
240
V_IN = 3.6V
200
70
–8V EFFICIENCY
160
65
120
60
55
50
0.1
80
15V LOSS
40
–8V LOSS
0
1
10
100
LOAD CURRENT (mA)
3463 TA01b
3463f
1