6.5 V, 1 A, Ultralow Noise, High PSRR, Fast Transient Response CMOS LDO Data Sheet ADM7171 FEATURES TYPICAL APPLICATION CIRCUIT Input voltage range: 2.3 V to 6.5 V ADM7171 V = 5V V = 3.3V IN OUT Maximum load current: 1 A VIN VOUT C C IN OUT VIN VOUT Low noise: 5 V rms independent of output voltage at 4.7F 4.7F SENSE 100 Hz to 100 kHz ON Fast transient response: 1.5 s for 1 mA to 500 mA load step EN SS C SS OFF 60 dB PSRR at 100 kHz 1nF GND Low dropout voltage: 42 mV at 500 mA load, V = 3 V OUT Initial accuracy: 0.5% (minimum), +1% (maximum) Figure 1. ADM7171 with Fixed Output Voltage, 3.3 V Accuracy over line, load, and temperature: 1.5% The ADM7171 regulator output noise is 5 V rms independent Quiescent current, I = 0.7 mA with no load GND of the output voltage. The ADM7171 is available in an 8-lead, Low shutdown current: 0.25 A at V = 5 V IN 3 mm 3 mm LFCSP, making it not only a very compact solution, Stable with small 4.7 F ceramic output capacitor but also providing excellent thermal performance for applications Adjustable and fixed output voltage options: 1.2 V to 5.0 V requiring up to 1 A of output current in a small, low profile Adjustable output from 1.2 V to V V IN DO footprint. Precision enable Adjustable soft start T 8-lead, 3 mm 3 mm LFCSP package Supported by ADIsimPower tool APPLICATIONS 1 Regulation to noise sensitive applications: ADC and DAC circuits, precision amplifiers, PLLs/VCOs, and clocking ICs Communications and infrastructure 2 Medical and healthcare Industrial and instrumentation GENERAL DESCRIPTION The ADM7171 is a CMOS, low dropout linear regulator (LDO) B B CH1 200mA CH2 10mV M400ns A CH3 100mV that operates from 2.3 V to 6.5 V and provides up to 1 A of output W W T 0.40% current. This high output current LDO is ideal for regulation of Figure 2. Transient Response (Trace 2), 1 mA to 500 mA Load Step in 400 ns high performance analog and mixed signal circuits operating (Trace 1) from 6 V down to 1.2 V rails. Using an advanced proprietary Table 1. Related Devices architecture, the device provides high power supply rejection and low noise, and achieves excellent line and load transient response Device Input Voltage Output Current Package with just a small 4.7 F ceramic output capacitor. Load transient ADM7170 2.3 V to 6.5 V 500 mA 8-lead LFCSP response is typically 1.5 s for a 1 mA to 500 mA load step. ADM7172 2.3 V to 6.5 V 2 A 8-lead LFCSP The ADM7171 is available in 17 fixed output voltage options. The following voltages are available from stock: 1.3 V, 1.8 V, 2.5 V, 3.0 V, 3.3 V, 4.2 V, and 5.0 V. Additional voltages that are available by special order are: 1.5 V, 1.85 V, 2.0 V, 2.2 V, 2.7 V, 2.75 V, 2.8 V, 2.85 V, 3.8 V, and 4.6 V. An adjustable version is also available that allows output voltages that range from 1.2 V to V IN VDO with an external feedback divider. Inrush current can be controlled by adjusting the start-up time via the soft start pin. The typical start-up time with a 1 nF soft start capacitor is 1.0 ms. Rev. E Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20142019 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 12298-001 12298-002ADM7171 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 ADIsimPower Design Tool ....................................................... 17 Applications ....................................................................................... 1 Capacitor Selection .................................................................... 17 General Description ......................................................................... 1 Programmable Precision Enable .............................................. 18 Typical Application Circuit ............................................................. 1 Undervoltage Lockout ............................................................... 18 Revision History ............................................................................... 2 Soft Start ....................................................................................... 18 Specif icat ions ..................................................................................... 3 Noise Reduction of the ADM7171 in Adjustable Mode ........... 19 Input and Output Capacitor, Recommended Specifications .. 4 Effect of Noise Reduction on Start-Up Time ......................... 19 Absolute Maximum Ratings ............................................................ 5 Current-Limit and Thermal Overload Protection ................. 19 Thermal Data ................................................................................ 5 Thermal Considerations ............................................................ 20 Thermal Resistance ...................................................................... 5 Typical Applications Circuits .................................................... 21 ESD Caution .................................................................................. 5 Printed Circuit Board Layout Considerations ............................ 22 Pin Configuration and Function Descriptions ............................. 6 Outline Dimensions ....................................................................... 23 Typical Performance Characteristics ............................................. 7 Ordering Guide .......................................................................... 23 Theory of Operation ...................................................................... 16 Applications Information .............................................................. 17 REVISION HISTORY 9/2019Rev. D to Rev. E 8/2015Rev. B to Rev. C Change to Figure 33 Caption ........................................................ 11 Changes to Soft Start Section ........................................................ 19 Added Effect of Noise Reduction on Start-Up Time Section ... 19 Change to Figure 34 Caption, Figure 38 Caption, and Figure 39 Caption ............................................................................................. 12 Changes to Figure 54 ...................................................................... 16 12/2014Rev. A to Rev. B Updated Outline Dimensions ....................................................... 23 Changes to Figure 2 ........................................................................... 1 Changes to Figure 48 to Figure 51 ................................................ 14 1/2018Rev. C to Rev. D Changes to Figure 52 to Figure 53 ................................................ 15 Updated Outline Dimensions ....................................................... 23 Changes to Figure 56 ...................................................................... 17 Changes to Ordering Guide .......................................................... 23 8/2014Rev. 0 to Rev. A Changes to Ordering Guide .......................................................... 23 7/2014Revision 0: Initial Version Rev. E Page 2 of 23