DATASHEET ISL85033 FN6676 Rev 8.00 Wide V Dual Standard Buck Regulator With 3A/3A Continuous Output Current IN February 17, 2015 The ISL85033 is a dual standard buck regulator capable of 3A Features per channel continuous output current. With an input range of Wide input voltage range from 4.5V to 28V 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 ISL85033 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 Selectable in-phase or out-of-phase PWM operation default frequency of 500kHz and it can be user programmed or synchronized from 300kHz to 2MHz. The ISL85033 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 ISL85033 is available in a small 4mmx4mm Thin Quad protection, UVLO Flat No-Lead (TQFN) Pb-free package. Boot undervoltage detection Pb-free (RoHS compliant) Related Literature AN1574 ISL85033DUALEVAL1Z Wide VIN Dual Standard Applications Buck Regulator With 3A/3A Output Current General purpose point-of-load DC/DC power conversion AN1585 ISL85033EVAL2Z (Small Form) Wide VIN Dual Set-top boxes Standard Buck Regulator With 3A/3A Output Current - Short Form FPGA power and STB power AN1584 ISL85033EVAL2Z (Small Form) Wide VIN Dual DVD and HDD drives Standard Buck Regulator With 3A/3A Output Current - Long LCD panels, TV power Form Cable modems AN1605 ISL85033CRSHEVAL1Z Wide VIN Current sharing Standard Buck Regulator With 6A Output Current 100 90 12V 1MHz 80 OUT 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 FN6676 Rev 8.00 Page 1 of 26 February 17, 2015 EFFICIENCY (%) ISL85033 Table of Contents Pin Configuration 3 Pin Descriptions . 3 Typical Application Schematics 5 Ordering Information 7 Absolute Maximum Ratings . 8 Thermal Information . 8 Recommended Operating Conditions 8 Electrical Specifications . 8 Typical Performance Curves . 10 Detailed Description 16 Operation Initialization 16 Power-on Reset and Undervoltage Lockout 16 Enable and Disable 16 Power-good . 16 Output Voltage Selection . 16 Output Tracking and Sequencing . 16 Protection Features . 17 Buck Regulator Overcurrent Protection . 17 Thermal Overload Protection 18 BOOT Undervoltage Protection . 18 Application Guidelines 18 Operating Frequency . 18 Synchronization Control 18 Output Inductor Selection . 18 Buck Regulator Output Capacitor Selection 18 Current Sharing Configuration . 19 Input Capacitor Selection . 19 Loop Compensation Design . 19 Theory of Compensation 20 PWM Comparator Gain Fm . 20 Power Stage Transfer Functions . 20 Rectifier Selection . 21 Power Derating Characteristics 22 Layout Considerations 22 Revision History 24 About Intersil 25 Package Outline Drawing 26 FN6676 Rev 8.00 Page 2 of 26 February 17, 2015