GENERAL DESCRIPTION
The LT3046 is a high-performance, low-dropout linear
regulator featuring Analog Devices, Inc. ultra-low noise
and ultra-high PSRR architecture for powering noisesensitive
applications. Designed as a precision current
reference followed by a high-performance voltage
buffer, the LT3046 can be easily paralleled to further
reduce noise, increase output current, and spread heat
on the PCB.
The device supplies 200mA at a typical 300mV dropout
voltage. Operating quiescent current is nominally
3.7mA and drops to 26μA in shutdown. The LT3046’s
wide output-voltage range (0.2V to 19V) while
maintaining unity-gain operation provides virtually
constant output noise, PSRR, bandwidth, and load
regulation, independent of the programmed output
voltage. Additionally, the regulator features
programmable current limit, fast start-up capability,
and programmable power good to indicate output
voltage regulation.
Built-in protection includes reverse-battery protection,
reverse-current protection, internal current limit with
foldback and thermal limit with hysteresis. The LT3046
is available in a thermally enhanced, 12-lead, 3mm ×
3mm, DFN package.

FEATURES
 Ultra-Low RMS Noise: 0.8μVRMS (10Hz to 100kHz)
 Ultra-Low Noise: 2.2nV/√Hz at 10kHz
 Ultra-Low 1/f Noise: 2.5μVP-P (0.1Hz to 10Hz)
 Ultra-High PSRR: 82dB at 1MHz
 Output Current: 200mA
 Wide Input-Voltage Range: 2.2V to 20V
 Single Capacitor Improves Noise and PSRR
 SET Pin Current: 100μA, ±0.5% Initial Accuracy
 Single Resistor Programs Output Voltage
 Programmable Current Limit
 Low Dropout Voltage: 300mV
 Output-Voltage Range: 0.2V to 19V
 Programmable Power Good
 Fast Start-Up Capability
 Precision Enable/UVLO
 Parallelable for Lower Noise and Higher Current
 Internal Current Limit with Foldback
 Minimum Output Capacitor: 4.7μF Ceramic
 Compact, Low-Profile, 12-Lead, 3mm × 3mm, DFN Package

APPLICATIONS
 RF Power Supplies: PLLs, VCOs, Mixers, LNAs, PAs
 Very Low-Noise Instrumentation
 High-Speed/High-Precision Data Converters
 Post-Regulator for Switching Supplies