LTC3026 Datasheet, PDF (1/16 Pages) Linear Technology – 1.5A Low Input Voltage VLDO Linear Regulator

FEATURES
■ _{Input Voltage Range:}
1.14V to 3.5V (with Boost Enabled)
1.14V to 5.5V (with External 5V Boost)
■ _{Low Dropout Voltage: 100mV at IOUT = 1.5A}
■ _{Adjustable Output Range: 0.4V to 2.6V}
■ _{Output Current: Up to 1.5A}
■ _{Excellent Supply Rejection Even Near Dropout}
■ _{Shutdown Disconnects Load from VIN and VBST}
■ _{Low Operating Current: IIN = 950µA at VIN = 1.5V}
■ _{Low Shutdown Current:}
I_IN < 1µA (Typ), I_BST = 0.1µA (Typ)
■ _{Stable with 10µF or Greater Ceramic Capacitors}
■ _{Short-Circuit, Reverse Current Protected}
■ _{Overtemperature Protected}
■ _{Available in 10-Lead MSOP and 10-Lead}
(3mm × 3mm) D_UFN Packages
APPLICATIO S
■ _{High Efficiency Linear Regulator}
■ _{Post Regulator for Switching Supplies}
■ _{Microprocessor Supply}
, LTC and LT are registered trademarks of Linear Technology Corporation.
VLDO is a trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Patent Pending
LTC3026
1.5A Low Input Voltage
VLDO Linear Regulator
DESCRIPTIO
The LTC^®3026 is a very low dropout (VLDO^TM) linear
regulator that can operate at input voltages down to 1.14V.
The device is capable of supplying 1.5A of output current
with a typical dropout voltage of only 100mV. To allow
operation at low input voltages the LTC3026 includes a
boost converter that provides the necessary headroom for
the internal LDO circuitry.
Output current comes directly from the input supply to
maximize efficiency. The boost converter requires only a
small chip inductor and ceramic capacitor for operation.
Additionally, the boosted output voltage of one LTC3026
can supply the boost voltage for other LTC3026s, thus
requiring a single inductor for multiple LDOs. A user
supplied boost voltage can be used eliminating the need
for an inductor altogether.
The LTC3026 regulator is stable with 10µF or greater
ceramic output capacitors. The device has a low 0.4V
reference voltage which is used to program the output
voltage via two external resistors. The device also has
internal current limit, overtemperature shutdown, and
reverse output current protection. The LTC3026 is avail-
able in a small 10-lead MSOP or low profile (0.75mm)
10-lead 3mm × 3mm DFN package.
TYPICAL APPLICATIO
1.2V Output Voltage from 1.5V Input Supply
V_IN = 1.5V
4.7µF
L1
10µH
IN
SW
5V BOOST ^BST
CONVERTER
4.7µF
OFF ON
0.4V +
–
OUT
SHDN
GND
ADJ
LTC3026
PG
L1: MURATA LQH2MCN100K02
8.06k
100k _4.02k
V_OUT = 1.2V,
1.5A
C_OUT
10µF
3026 TA01a
Dropout Voltage vs Output Current
150
100
1.2V
1.5V
2.0V
2.6V
50
0
0
0.5
1.0
1.5
I_OUT (A)
3026 TA01b
3026f
1