LT3462/LT3462A
Inverting 1.2MHz/2.7MHz
DC/DC Converters with
Integrated Schottky in ThinSOT
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FEATURES
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DESCRIPTIO
The LT®3462/LT3462A are general purpose fixed frequency current mode inverting DC/DC converters. Both
devices feature an integrated Schottky and a low VCESAT
switch allowing a small converter footprint and lower parts
cost. The LT3462 switches at 1.2MHz while the LT3462A
switches at 2.7MHz. These high speeds enable the use of
tiny, low cost and low height capacitors and inductors.
Integrated Schottky Rectifier
Fixed Frequency 1.2MHz/2.7MHz Operation
Very Low Noise: 1mVP-P Output Ripple
Low VCESAT Switch: 270mV at 250mA
–5V at 100mA from 5V Input
–12V at 30mA from 3.3V Input
Low Input Bias Current GND Based FB Input
Low Impedance (40Ω) 1.265V Reference Output
High Output Voltage: Up to – 38V
Wide Input Range: 2.5V to 16V
Uses Tiny Surface Mount Components
Low Shutdown Current: <10µA
Low Profile (1mm) SOT-23 (ThinSOTTM) Package
The LT3462/LT3462A operate in a dual inductor inverting
topology that filters both the input and output currents.
Very low output voltage ripple approaching 1mVP-P can be
achieved when ceramic capacitors are used. Fixed frequency switching ensures a clean output free from low
frequency noise typically present with charge pump solutions. The 40V switch allows a VIN to VOUT differential of
up to 38V for dual inductor topologies.
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APPLICATIO S
CCD Bias
LCD Bias
GaAs FET Bias
General Purpose Negative Voltage Supply
Both devices provide a low impedance 1.265V reference
output to supply the feedback resistor network. A ground
referenced, high impedance FB input allows high feedback
resistor values without compromising output accuracy.
, LTC and LT are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation
The LT3462/LT3462A are available in a 6-lead SOT-23
package.
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TYPICAL APPLICATIO
5V to –5V, 100mA Inverting DC/DC Converter
SW
VIN
TA = 25°C
22µH
D
FB
LT3462A
VIN = 5V
267k
68.1k
22pF
VOUT
–5V
100mA
10µF
SDREF
GND
70
EFFICIENCY (%)
1µF
75
1µF
22µH
VIN
5V
Efficiency
VIN = 3.3V
65
60
3462 TA01
55
0
20
60
80
40
LOAD CURRENT (mA)
100
3462 TA01b
3462af
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