Features

• Ultralow RMS Noise: 0.8μV_RMS (10Hz to 100kHz)
• Ultralow Spot Noise: 2nV/√Hz at 10kHz
• Ultrahigh PSRR: 76dB at 1MHz
• Output Current: 500mA
• Wide Input Voltage Range: 1.8V to 20V
• Single Capacitor Improves Noise and PSRR
• 100μA SET Pin Current: ±1% Initial Accuracy
• Single Resistor Programs Output Voltage
• High Bandwidth: 1MHz
• Programmable Current Limit
• Low Dropout Voltage: 260mV
• Output Voltage Range: 0V to 15V
• 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: 10μF Ceramic
• Reverse Battery and Reverse Current Protection
• 12-Lead MSOP and 10-Lead 3mm × 3mm DFN Packages

Typical Application

Description

The LT®3045 is a high performance low dropout linear regulator featuring LTC’s ultralow noise and ultrahigh PSRR architecture for powering noise sensitive applications. Designed as a precision current reference followed by a high performance voltage buffer, the LT3045 can be easily paralleled to further reduce noise, increase output current and spread heat on the PCB.

The device supplies 500mA at a typical 260mV dropout voltage. Operating quiescent current is nominally 2.2mA and drops to <<1μA in shutdown. The LT3045’s wide output voltage range (0V to 15V) while maintaining unitygain 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.

The LT3045 is stable with a minimum 10μF ceramic output capacitor. Built-in protection includes reverse battery protection, reverse current protection, internal current limit with foldback and thermal limit with hysteresis. The LT3045 is available in thermally enhanced 12-Lead MSOP and 10-Lead 3mm × 3mm DFN packages.