LT3483_15 Datasheet, PDF (1/12 Pages) Linear Technology – Inverting Micropower DC/DC Converters with Schottky

FEATURES
n _{Internal 40V Schottky Diode}
n _{One Resistor Feedback (Other Resistor Inside)}
n _{Internal 40V, 200mA/400mA Power Switch}
n _{Generates Regulated Negative Outputs to –38V}
n _{Low Quiescent Current:}
40µA in Active Mode
<1µA in Shutdown Mode
n _{Low VCESAT Switch: 200mV at 150mA}
n _{Wide Input Range: 2.5V to 16V}
n _{Uses Small Surface Mount Components}
n _{Output Short-Circuit Protected}
n _{Available in a 6-Lead SOT-23 (LT3483 Only) and}
Low Profile 8-Lead DFN (2mm × 2mm × 0.75mm)
Packages
APPLICATIONS
n _{LCD Bias}
n _{Handheld Computers}
n _{Battery Backup}
n _{Digital Cameras}
n _{OLED Bias}
LT3483/LT3483A
Inverting Micropower
DC/DC Converters
with Schottky
DESCRIPTION
The LT^®3483/LT3483A are micropower inverting DC/DC
converters with integrated Schottky and one resistor
feedback. The small package size, high level of integration
and use of tiny surface mount components yield a solution
size as small as 40mm². The devices feature a quiescent
current of only 40µA at no load, which further reduces
to 0.1µA in shutdown. A current limited, fixed off-time
control scheme conserves operating current, resulting
in high efficiency over a broad range of load current. A
precisely trimmed 10µA feedback current enables one
resistor feedback and virtually eliminates feedback load-
ing of the output. The 40V switch enables voltage outputs
up to –38V to be generated without the use of costly
transformers. The LT3483/LT3483A’s low 300ns off-time
permits the use of tiny low profile inductors and capaci-
tors to minimize footprint and cost in space-conscious
portable applications.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners. Protected by U.S. Patents, including 7710700.
TYPICAL APPLICATION
V_IN
3.6V
4.7µF
3.6V to –8V DC/DC Converter
10µH
0.22µF
SW
V_IN
D
LT3483
SHDN FB
GND
10Ω
5pF 806k
V_OUT
–8V
25mA
2.2µF
3483 TA01a
Efficiency and Power Loss
75 _{VIN = 3.6V}
1000
EFFICIENCY
70
100
65
10
POWER
LOSS
60
1
55
0.1
1
10
LOAD CURRENT (mA)
0.1
100
3483 TA01b
3483fc
1