XXRRPP77667744 22AA 1188VV SSyynncchhrroonnoouuss PPFFMM//PPWWMM SStteepp--DDoowwnn RReegguullaattoorr February 2013 Rev. 1.0.0 GENERAL DESCRIPTION APPLICATIONS The XRP7674 is a 2A capable synchronous Distributed Power Architecture current-mode PWM step down (buck) voltage Portable Equipment regulator with improved light current load efficiency. A wide 4.5V to 18V input voltage Point of Load Converter range allows for single supply operations from Audio-Video Equipment industry standard 5V and 12V power rails. With a 340kHz constant operating frequency FEATURES and integrated high and low-side 100m/100m MOSFETs, the XRP7674 2A Continuous Output Current reduces the overall component count and 4.5V to 18V Wide Input Voltage solution footprint. Current-mode control 0.925V to 16V Adjustable Output Voltage provides fast transient response and cycle-by- cycle OCP. An adjustable soft-start prevents 2% Output Voltage Accuracy inrush current at turn-on, and in shutdown PWM Current-Mode Control mode the supply current drops to 0.1A. At 340kHz Constant Operations light current loads, the XRP7674 operates in Discontinuous Conduction Mode (DCM) and is Up to 95% Efficiency complemented by a pulse frequency Light-Load efficiency modulation mode (PFM) to provide excellent Discontinuous Conduction Mode (DCM) conversion efficiency. Pulse Frequency Modulation Mode (PFM) Built-in output over-voltage (open load), over temperature, cycle-by-cycle over-current, Programmable Soft-Start and Enable under-voltage lockout (UVLO) and hiccup Function mode short-circuit protection insures safe Built-in Thermal, Over-Current, UVLO, operation under abnormal operating Output Over-Voltage and hiccup mode conditions. short-circuit protection The XRP7674 is offered in a RoHS compliant, RoHS Compliant, Green/Halogen green/halogen free 8-pin SOIC package. Free 8-Pin SOIC Package TYPICAL APPLICATION DIAGRAM Fig. 1: XRP7674 Application Diagram Exar Corporation www.exar.com 48720 Kato Road, Fremont CA 94538, USA Tel. +1 510 668-7000 Fax. +1 510 668-7001 XXRRPP77667744 22AA 1188VV SSyynncchhrroonnoouuss PPFFMM//PPWWMM SStteepp--DDoowwnn RReegguullaattoorr ABSOLUTE MAXIMUM RATINGS OPERATING RATINGS These are stress ratings only and functional operation of Input Voltage V ......................................... 4.5V to 18V IN the device at these ratings or any other above those Ambient Operating Temperature ................ -40C to 85C indicated in the operation sections of the specifications Maximum Output Current.................................... 2A min below is not implied. Exposure to absolute maximum Thermal Resistance .....................................105C/W JA rating conditions for extended periods of time may affect reliability. Supply Voltage V ...................................... -0.3V to 20V IN Switch Node Voltage V ......................................... 21V SW Boost Voltage VBS ................................... -0.3 to VSW+6V Enable Voltage V ......................................... -0.3 to V EN IN All Other Pins .............................................. -0.3 to +6V Junction Temperature .......................................... 150C Storage Temperature .............................. -65C to 150C Lead Temperature (Soldering, 10 sec) ................... 260C ESD Rating (HBM - Human Body Model) .................... 2kV ESD Rating (MM - Machine Model) ........................... 200V Moisture Sensitivity Level (MSL) ................................... 3 ELECTRICAL SPECIFICATIONS Specifications are for an Operating Ambient Temperature of T = 25C only limits applying over the full Ambient Operating A Temperature range are denoted by a . Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at T = 25C, and are provided for reference purposes A only. Unless otherwise indicated, V = V = 12V, V =3.3V. IN EN OUT Parameter Min. Typ. Max. Units Conditions Shutdown Supply Current 0.1 10 A V =0V EN Quiescent Current 1.2 1.4 mA V =3V, V =1V EN FB Feedback Voltage V 0.907 0.925 0.943 V FB Feedback Overvoltage Threshold 1.1 V Feedback Bias Current 0.1 A V =1V -0.1 FB 1 Error Amplifier Voltage Gain A 400 V/V EA Error Amplifier 800 A/V Transconductance G EA COMP to Current Sense 3.5 A/V Transconductance G CS High-Side switch On Resistance 100 m I =0.2A&0.7A SW 2 R DSONH Low-Side switch On Resistance 100 m I =-0.2A&-0.7A SW 2 R DSONL High-Side switch Leakage 0.1 10 A V =18V, V =0V, V =0V IN EN SW Current High-Side Switch Current Limit 3.5 A 2.7 Low-Side Switch Current Limit Drain to Source 0 A Oscillator Frequency F 280 340 400 kHz OSC1 Short Circuit Oscillator 90 kHz Frequency F OSC2 Maximum Duty Cycle D 90 % V =0.85V MAX FB Minimum Duty Cycle D 0 % V =1V MIN FB Minimum Start-up Current 10 mA V 4.75V IN Minimum No Load Start-up 5 V I =0A OUT Voltage Minimum Full Load Start-up 4.75 V I =2A OUT Voltage 2013 Exar Corporation 2/12 Rev. 1.0.0