DATASHEET ISL78208 FN8354 Rev 1.00 Wide V Dual Standard Buck Regulator with 3A/3A Continuous Output Current IN July 29, 2014 The ISL78208 is a dual standard buck regulator capable of 3A Features per channel with continuous output current. With an input Wide input voltage range from 4.5V to 28V range of 4.5V to 28V, it provides a high frequency power solution for a variety of point of load applications. Adjustable output voltage with continuous output current up to 3A The PWM controller in the ISL78208 drives an internal switching N-Channel power MOSFET and requires an external Current mode control Schottky diode to generate the output voltage. The integrated Adjustable switching frequency from 300kHz to 2MHz power switch is optimized for excellent thermal performance Independent power-good detection up to 3A of output current. The PWM regulator switches at a default frequency of 500kHz and it can be user programmed Selectable In-phase or out-of-phase PWM operation or synchronized from 300kHz to 2MHz. The ISL78208 utilizes Independent, sequential, ratiometric or absolute tracking peak current mode control to provide flexibility in component between outputs selection and minimize solution size. The protection features Internal 2ms Soft-start time include overcurrent, UVLO and thermal overload protection. Overcurrent/short circuit protection, thermal overload The ISL78208 is available in 5mmx5mm 32 Ld Wettable protection, UVLO Flank Quad Flat Pb-free (WFQFN) package. Boot undervoltage detection The ISL78208 is rated for the automotive temperature range Qualified for automotive applications (-40C to +105C). Pb-Free (RoHS compliant) Applications DSP and embedded processor power supply Infotainment system power 100 90 12V 1MHz OUT 80 70 60 50 40 0.0 0.5 1.0 1.5 2.0 2.5 3.0 OUTPUT LOAD (A) FIGURE 1. EFFICIENCY vs LOAD, V = 28V, T = +25C IN A FN8354 Rev 1.00 Page 1 of 24 July 29, 2014 EFFICIENCY (%) ISL78208 Table of Contents Pin Configuration 3 Pin Descriptions . 3 Ordering Information 4 Typical Application Schematics 5 Functional Block Diagram 6 Absolute Maximum Ratings . 7 Thermal Information . 7 Recommended Operating Conditions 7 Electrical Specifications . 7 Detailed Description 15 Operation Initialization 15 Power-On Reset and Undervoltage Lockout 15 Enable and Disable 15 Power-Good 15 Output Voltage Selection . 15 Output Tracking and Sequencing . 15 Protection Features . 16 Buck Regulator Overcurrent Protection . 16 Thermal Overload Protection 17 BOOT Undervoltage Protection . 17 Application Guidelines 17 Operating Frequency . 17 Synchronization Control 17 Output Inductor Selection . 17 Buck Regulator Output Capacitor Selection 17 Current Sharing Configuration . 18 Input Capacitor Selection . 18 Loop Compensation Design . 18 Theory of Compensation 19 PWM Comparator Gain Fm . 19 Power Stage Transfer Functions . 19 Rectifier Selection . 20 Power Derating Characteristics 21 Layout Considerations 21 Revision History 23 About Intersil 23 Package Outline Drawing 24 FN8354 Rev 1.00 Page 2 of 24 July 29, 2014