LT3029
Dual 500mA/500mA
Low Dropout, Low Noise,
Micropower Linear Regulator
DESCRIPTION
FEATURES
The LT®3029 is a dual, micropower, low noise, low drop-
out linear regulator. The device operates either with a
common input supply or independent input supplies for
each channel, over an input voltage range of 1.8V to 20V.
Each output supplies up to 500mA of output current with
a typical dropout voltage of 300mV. Quiescent current is
well controlled in dropout. With an external 10nF bypass
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Output Current: 500mA per Channel
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Low Dropout Voltage: 300mV
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Low Noise: 20μV
(10Hz to 100kHz)
RMS
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Low Quiescent Current: 55μA per Channel
Wide Input Voltage Range: 1.8V to 20V (Common or
Independent Input Supply)
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Adjustable Output: 1.215V Reference Voltage
Very Low Quiescent Current in Shutdown: <1μA per
Channel
Stable with 3.3μF Minimum Output Capacitor
Stable with Ceramic, Tantalum or Aluminum
Electrolytic Capacitors
Reverse-Battery and Reverse Output-to-Input
Protection
Current Limit with Foldback and Thermal Shutdown
Tracking/Sequencing Capability: Compatible with
LTC292X Power Supply Tracking ICs
Thermally Enhanced 16-Lead MSOP and 16-Lead
(4mm × 3mm) DFN Packages
capacitor, output noise is only 20μV
over a 10Hz to
RMS
100kHz bandwidth. Designed for use in battery-powered
systems,thelow55μAquiescentcurrentperchannelmakes
it an ideal choice. In shutdown, quiescent current drops to
less than 1μA. Shutdown control is independent for each
channel, allowing for flexible power management.
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TheLT3029optimizesstabilityandtransientresponsewith
low ESR ceramic output capacitors, requiring a minimum
of only 3.3μF. The regulator does not require the addition
of ESR, as is common with other regulators.
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Internal circuitry provides reverse-battery protection,
reverse-current protection, current limiting with foldback
and thermal shutdown. The device is available as an
adjustable output voltage device with a 1.215V reference
voltage. The LT3029 is offered in the thermally enhanced
16-lead MSOP and 16-lead, low profile (4mm × 3mm ×
0.75mm) DFN packages.
APPLICATIONS
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General Purpose Linear Regulator
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Battery-Powered Systems
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Microprocessor Core/Logic Supplies
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
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Post Regulator for Switching Supplies
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Tracking/Sequencing Power Supplies
Dropout Voltage vs Load Current
TYPICAL APPLICATION
400
T
= 25°C
2.5VIN to 1.5V/1.8V Application
J
350
300
250
200
150
100
50
V
IN
2.5V
V
OUT1
IN1
OUT1
LT3029
1.8V
10nF
500mA
113k
1%
3.3μF
3.3μF
3.3μF
BYP1
ADJ1
IN2
237k
1%
SHDN1
V
OUT2
1.5V
SHDN2 OUT2
500mA
10nF
54.9k
1%
BYP2
ADJ2
0
237k
1%
GND
0
50 100 150 200 250 300 350 400 450 500
OUTPUT CURRENT (mA)
3029 TA01b
3029 TA01
3029f
1