Quad, 1 A, 5.5 V, Synchronous Step-Down Regulators with One RF LDO Regulator Data Sheet ADP5138 FEATURES TYPICAL APPLICATION CIRCUIT V OUT1 PVINx voltage range: 3 V to 5.5 V ADP5138 Continuous output current R POR POR Channel 1 to Channel 4 (buck): 1 A AVIN POR C AVIN Channel 5 (LDO): 250 mA L1 V = 3.3V OUT1 EN1 V = 5V 10% SW1 IN 3.2 MHz fixed PWM switching frequency PVIN1 FB1 C OUT1 Synchronization input function C IN1 PGND1 Buck regulators run at 90 out of phase L2 V = 1.0V OUT2 EN2 Individual precision enable input SW2 PVIN2 C R Power-on reset output OUT2 TOP2 C IN2 FB2 Integrated compensation R BOT2 PGND2 Soft start and power-up sequencing reduce inrush current L3 V = 1.25V OUT3 EN3 SW3 Active output discharge switch function PVIN3 C R TOP3 OUT3 Stable with low ESR output ceramic capacitors C IN3 FB3 OVLO, UVM, and UVLO R BOT3 PGND3 TSD protection L4 V = 1.35V OUT4 EN4 SW4 Qualified for automotive applications PVIN4 FB4 C OUT4 C IN4 APPLICATIONS PGND4 Automotive V = 1.8V OUT5 EN5 VOUT5 Industrial and instrumentation R TOP5 PVIN5 C FB5 OUT5 DC to dc point of load applications C IN5 SYNC GND R BOT5 Figure 1. GENERAL DESCRIPTION The ADP5138 integrates four high performance synchronous The ADP5138 integrates internal compensation to simplify step-down regulators and one low noise radio frequency (RF) the design. The internal soft start circuitry and power-up low dropout (LDO) regulator. The device runs from PVINx sequencing help reduce the input inrush current. input voltages of 3 V to 5.5 V. The output voltage of each The ADP5138 monitors the input voltage and provides input channel is factory set or can be programmed down to 0.8 V overvoltage lockout (OVLO), undervoltage monitor (UVM), with a resistor. Each step-down regulator can provide up to 1 A and undervoltage lockout (UVLO) features. It also monitors the of continuous output current and the LDO can provide 250 mA undervoltage and overvoltage of the outputs. The power-on of output current. reset (POR) signal is asserted when the input or output voltage The ADP5138 runs at the fixed PWM switching frequency, fault occurs. 3.2 MHz, or can be synchronized to the external clock from Additional protection includes overcurrent protection (OCP) 2.8 MHz to 3.5 MHz, which is outside the amplitude and thermal shutdown (TSD). modulation (AM) band. The four buck regulators run at 90 The ADP5138 operates over the 40C to +125C operating out of phase to reduce the input ripple current and the input temperature range (junction), and is available in a 28-lead capacitor size, thereby helping to lower system electromagnetic LFCSP package. interference (EMI). Rev. A 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 2018 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com 16669-001ADP5138 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Input Overvoltage Lockout (OVLO) ....................................... 17 Applications ....................................................................................... 1 Input Undervoltage Monitor (UVM) ...................................... 17 Typical Application Circuit ............................................................. 1 Input Undervoltage Lockout (UVLO) ..................................... 17 General Description ......................................................................... 1 Output Voltage Power-Good .................................................... 17 Table of Contents .............................................................................. 2 Power-On Reset (POR) ............................................................. 18 Revision History ........................................................................... 2 Soft Start and Power-Up Sequence .......................................... 18 Functional Block Diagram .............................................................. 3 Current-Limit and Short-Circuit Protection .......................... 18 Specifications ..................................................................................... 4 Active Output Discharge ........................................................... 19 Buck Regulator Specifications .................................................... 5 Thermal Shutdown .................................................................... 19 LDO Regulator Specifications .................................................... 6 Applications Information .............................................................. 20 Absolute Maximum Ratings ............................................................ 7 Input Capacitor Selection .......................................................... 20 Thermal Resistance ...................................................................... 7 Output Voltage Setting .............................................................. 20 ESD Caution .................................................................................. 7 Inductor Selection ...................................................................... 20 Pin Configuration and Function Descriptions ............................. 8 Output Capacitor Selection....................................................... 20 Typical Performance Characteristics ........................................... 10 Application Circuit ..................................................................... 21 Theory of Operation ...................................................................... 17 Factory-Programmable Options .................................................. 22 Control Scheme .......................................................................... 17 Outline Dimensions ....................................................................... 23 Precision Enable and Shutdown ............................................... 17 Ordering Guide .......................................................................... 23 Oscillator and Phase Shift ......................................................... 17 Automotive Products ................................................................. 23 Synchronization .......................................................................... 17 REVISION HISTORY 8/2018Rev. 0 to Rev. A Change to Figure 2 ........................................................................... 3 5/2018Revision 0: Initial Version Rev. A Page 2 of 23