Isolated Switching Regulator with Quad-Channel Isolators Data Sheet ADuM4470/ADuM4471/ADuM4472/ADuM4473/ADuM4474 FEATURES FUNCTIONAL BLOCK DIAGRAM V ISO V DD1 Isolated PWM feedback with built in compensation RECT Primary side transformer driver for up to 2.5 W output power V REG with 5 V input voltage ADuM4470/ Regulated adjustable output: 3.3 V to 24 V ADuM4471/ ADuM4472/ Up to 80% efficiency V DD2 ADuM4473/ REG Quad dc-to-25 Mbps (NRZ) signal isolation channels ADuM4474 5V PRIMARY V DDA CONTROLLER/ 200 kHz to 1 MHz adjustable oscillator SECONDARY FB DRIVER CONTROLLER Soft start function at power-up INTERNAL OC FEEDBACK Pulse-by-pulse overcurrent protection I/OA I/OA Thermal shutdown CHA 5000 V rms isolation I/OB I/OB PRIMARY SECONDARY High common-mode transient immunity: >25 kV/s DATA I/O CHB DATA I/O 4-CHANNEL 4-CHANNEL 20-lead SOIC package with 8.3 mm creepage I/OC I/OC CHC High temperature operation: 105C I/OD I/OD CHD APPLICATIONS GND GND 1 2 Power supply start-up bias and gate drives Figure 1. Isolated sensor interfaces Process controls RS-232/RS-422/RS-485 transceivers GENERAL DESCRIPTION The regulated feedback provides a relatively flat efficiency curve The ADuM4470/ADuM4471/ADuM4472/ADuM4473/ 1 ADuM4474 are quad-channel, digital isolators with a regu- over the full output power range. The ADuM447x enable a dc- lated dc-to-dc isolated power supply controller and an internal to-dc converter with a 3.3 V to 24 V isolated output voltage MOSFET driver. The dc-to-dc controller has an internal isolated range from either a 5.0 V or a 3.3 V input voltage, with an PWM feedback from the secondary side, based on the output power of up to 2.5 W. iCoupler chip scale transformer technology and complete loop The ADuM447x isolators provide four independent isolation compensation. This eliminates the need to use an optocoupler channels in a variety of channel configurations and data rates. for feedback and compensates the loop for stability. (The x in ADuM447x throughout this data sheet stands for the ADuM4470/ADuM4471/ADuM4472/ADuM4473/ADuM4474.) The ADuM447x isolators provide a more stable output voltage and higher efficiency compared to unregulated isolated dc- to-dc power supplies. The fully integrated feedback and loop compensation in a wide-body SOIC package provide a smaller form factor and 8.3 mm creepage distance solution. 1 Protected by U.S. Patents 5,952,849 6,873,065 and 7075 329 B2. Other patents pending. Rev. 0 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 2012 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. 10991-001ADuM4470/ADuM4471/ADuM4472/ADuM4473/ADuM4474 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Pin Configurations and Function Descriptions ......................... 15 Applications ....................................................................................... 1 Typical Performance Characteristics ........................................... 20 Functional Block Diagram .............................................................. 1 Applications Information .............................................................. 26 General Description ......................................................................... 1 Theory of Operation .................................................................. 26 Revision History ............................................................................... 2 Application Schematics ............................................................. 26 Block Diagrams of I/O Channels.................................................... 3 Transformer Design ................................................................... 27 Specif icat ions ..................................................................................... 4 Transformer Turns Ratio ........................................................... 27 Electrical Characteristics5 V Primary Input Supply/ Transformer ET Constant ......................................................... 27 5 V Secondary Isolated Supply ................................................... 4 Transformer Primary Inductance and Resistance ................. 28 Electrical Characteristics3.3 V Primary Input Supply/ Transformer Isolation Voltage .................................................. 28 3.3 V Secondary Isolated Supply ................................................ 6 Switching Frequency .................................................................. 28 Electrical Characteristics5 V Primary Input Supply/ Transient Response .................................................................... 28 3.3 V Secondary Isolated Supply ................................................ 8 Component Selection ................................................................ 29 Electrical Characteristics5 V Primary Input Supply/ 15 V Secondary Isolated Supply ............................................... 10 Printed Circuit Board (PCB) Layout ....................................... 29 Package Characteristics ............................................................. 12 Thermal Analysis ....................................................................... 30 Propagation Delay-Related Parameters ................................... 30 Regulatory Approvals (Pending) .............................................. 12 Insulation and Safety-Related Specifications .......................... 12 DC Correctness and Magnetic Field Immunity ........................... 30 DIN V VDE V 0884-10 (VDE V 0884-10) Insulation Power Consumption .................................................................. 31 Characteristics ............................................................................ 13 Power Considerations ................................................................ 32 Recommended Operating Conditions .................................... 13 Insulation Lifetime ..................................................................... 33 Absolute Maximum Ratings .......................................................... 14 Outline Dimensions ....................................................................... 34 ESD Caution ................................................................................ 14 Ordering Guide .......................................................................... 34 REVISION HISTORY 12/12Revision 0: Initial Version Rev. 0 Page 2 of 36