Datasheet LT3070 (Analog Devices)

LT3070 5A, Low Noise, Programmable Output, 85mV Dropout Linear Regulator
FEATURES DESCRIPTION
n
Output Current: 5A
The LT®3070 is a low voltage, UltraFast™ transient re- n
Dropout Voltage: 85mV Typical
sponse linear regulator. The device supplies up to 5A of n
Digitally Programmable VOUT : 0.8V to 1.8V
output current with a typical dropout voltage of 85mV. n
Digital Output Margining: ±1%, ±3% or ±5%
A 0.01µF reference bypass capacitor decreases output n
Low Output Noise: 25µVRMS (10Hz to 100kHz)
voltage noise to 25µVRMS. The LT3070’s high bandwidth n
Parallel Multiple Devices for 10A or More
permits the use of low ESR ceramic capacitors, saving n
Precision Current Limit: ±20%
bulk capacitance and cost. The LT3070’s features make n ±1% Accuracy Over Line, Load and Temperature it ideal for high performance FPGAs, microprocessors or n Stable with Low ESR Ceramic Output Capacitors sensitive communication supply applications. (15µF Minimum) Output voltage is digitally selectable in 50mV increments n High Frequency PSRR: 30dB at 1MHz over a 0.8V to 1.8V range. A margining function allows n Enable Function Turns Output On/Off the user to adjust system output voltage in increments of n VIOC Pin Controls Buck Converter to Maintain Low ±1%, ±3% or ±5%. The IC incorporates a unique tracking Power Dissipation and Optimize Efficiency function to control a buck regulator powering the LT3070’s n PWRGD/UVLO/Thermal Shutdown Flag input. This tracking function drives the buck regulator to n Current Limit with Foldback Protection maintain the LT3070’s input voltage to VOUT + 300mV, n Thermal Shutdown minimizing power dissipation. n 28-Lead (4mm × 5mm × 0.75mm) QFN Package Internal protection includes UVLO, reverse-current protec-
APPLICATIONS
tion, precision current limiting with power foldback and thermal shutdown. The LT3070 regulator is available in a n FPGA and DSP Supplies thermally enhanced 28-lead, 4mm × 5mm QFN package. n ASIC and Microprocessor Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Servers and Storage Devices UltraFast and VLDO are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Patents pending. n Post Buck Regulation and Supply Isolation
TYPICAL APPLICATION Dropout Voltage 0.9V, 5A Regulator
150 50k VIN = VOUT(NOMINAL) VBIAS PWRGD 2.2V TO 3.6V 2.2µF 120 BIAS VIN IN 1.2V PWRGD 330µF EN SENSE VOUT TAGE (mV) 90 VOUT = 1.8V V LT3070 O0 OUT 0.9V VBIAS = 3.3V V 2.2µF* 4.7µF* 10µF* 5A O1 60 VO2 VOUT = 0.8V MARGSEL *X5R OR X7R CAPACITORS DROPOUT VOL VBIAS = 2.5V MARGTOL 30 VIOC REF/BYP 1nF GND 0.01µF 0 0 1 2 3 4 5 3070 TA01a OUTPUT CURRENT (A) 3070 TA01b 3070fc For more information www.linear.com/LT3070 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Applications Information Package Description Revision History Typical Application Related Parts