SC4525ESETRT Semtech

SC4525E 28V 3A Step-Down Switching Regulator POWER MANAGEMENT Features Description Wide Input Voltage Range: 3V to 28V The SC4525E is a constant frequency peak current-mode 3A Output Current step-down switching regulator capable of producing 3A 200kHz to 2MHz Programmable Frequency output current from an input ranging from 3V to 28V. The Precision V F eedback Voltage switching frequency of the SC4525E can be programmed Peak Current-Mode Control up to 2MHz for component miniaturization or it can be Cycle-by-Cycle Current Limiting set at lower frequencies to accommodate high step-down Hiccup Overload Protection with Frequency Foldback ratios. The SC4525E is suitable for next generation XDSL Soft-Start and Enable modems, high-definition TVs and various point of load Thermal Shutdown applications. Thermally Enhanced 8-pin SOIC Package Fully RoHS and WEEE Compliant Peak current-mode PWM control employed in the SC4525E achieves fast transient response with simple loop compensation. Cycle-by-cycle current limiting and hiccup Applications overload protection reduces power dissipation during output overload. Soft-start function reduces input start- XDSL and Cable Modems up current and prevents the output from overshooting Set Top Boxes during power-up. Point of Load Applications CPE Equipment The SC4525E is available in SOIC-8 EDP package. DSP Power Supplies LCD and Plasma TVs Automotive Car Audio S C 4525A Typical Application Circuit Efficiency 90 D 1 10V 28V V IN 1N 4148 C 4 C 1 80 4.7 mF 0.33 mF V IN = 24V B S T IN V IN = 12V L1 O U T S W 5.2 mH 5V /3A 70 R 4 S C 4525E S S /E N 33.2k F B 60 C O M P R O S C G N D C 7 D 2 R 6 C 2 R 5 R 7 50 C 8 20B Q 030 8.25k 10 mF X3 15.8k 12.7k 22nF 22pF C 5 2.2nF 40 0.0 0.5 1.0 1.5 2.0 2.5 3.0 L1: C oiltronics C D 1- 5R 2 C 2: M urata G R M 31C R 60J106K Load Current (A) C 4: M urata G R M 32E R 71H 475K Figure 1. 1MHz 10V -28V to 5V/3A Step-down Converter Rev. 2. E fficiency of the 1M H z 10V -28V to 5V /3A S tep-D ow n C onverter (Front P age) 20 3 Se mtech Corporation Efficiency (%)SC4525E Pin Configuration Ordering Information Device Package ( )(2 ) SC4525ESETRT SOIC-8 EDP SW 1 8 B S T SC4525EEVB Evaluation Board IN 2 7 FB Notes: 9 R O S C 3 6 C O M P ( ) Available in tape and reel only. A reel contains 2,500 devices. (2) Available in lead-free package only. Device is fully WEEE and RoHS G N D 4 5 S S /E N compliant and halogen-free. (8 - Pin SOIC - EDP) Marking Information yyww=Date code (Example: 0752) xxxxx=Semtech Lot No. (Example: E90 0) 2