RS2576 52KHz, 3A PWM Buck DC/DC Converter DESCRIPTION The RS2576 is Monolithic IC that design for a step-down DC/DC Converter, and own the ability of driving a 3A load without additional transistor component. The output version is an adjustable type. It operates at a switching frequency of 52KHz and include internal frequency compensation. Other features include a guaranteed ± 4% tolerance on output voltage under specified input voltage and output load conditions, and ± 10% on the oscillator frequency. Regarding protected function, thermal shutdown is to prevent over temperature operating from damage, and current limit is against over current operating of the output switch. FEATURES Adjustable version output voltage range: 1.23-37V ± 4% max over line and load conditions 52KHz ± 10% fixed switching frequency TTL shutdown capability Operating voltage can be up to 40V Output load current: 3A TO263-5 package Low power standby mode Thermal-shunt down and current-limit protection Built-in switching a transistor on chip, requires only 4 external components APPLICATIONS Simple High-efficiency step-down regulator Positive to negative converter On-card switching regulators BLOCK DIAGRAM Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, No. 233-1, Baociao Rd., Sindian Dist., New Taipei City 23145, Taiwan RS2576 APPLICATION CIRCUIT V1.1 2 August 2014 RS2576 ORDER INFORMATION Device RS2576-XX Y Z Device Code XX is nominal output voltage AD=ADJ Y is package designator: U: TO-263-5 Z is Lead Free designator: P: Commercial Standard, Lead (Pb) Free and Phosphorous (P) Free Package G: Green (Halogen Free with Commercial Standard) PIN CONFIGURATION TO-263-5 PIN DESCRIPTION Pin Name VIN VOUT GND FB SD V1.1 Description Regulator Input Pin Regulator Output Pin Ground Pin Output Voltage Feed Back Control Pin ON/OFF Shutdown Pin 3 Pin No. 1 2 3, 6 4 5 August 2014 RS2576 ABSOLUTE MAXIMUM RATINGS Parameter Supply voltage On/Off pin input voltage Feedback pin voltage Output voltage to ground Power dissipation Storage temperature Operating junction temperature range Operating voltage (Note1) Symbol VCC VSD VFB VOUT PD Tstg TJ VOP ELECTRICAL CHARACTERISTICS Range 45 -0 .3 ~+VI N -0.3~+25 -1 Internally Limited -40~+150 -40~+125 +4.5~+40 Units V V V V W ℃ ℃ V (CONTINUED) (Note 2) Specifications with boldface type apply over for full operating temperature range, the other type are for TJ=25℃ Typ. Max. Part No. Parameter Symbol Conditions Min. Unit (Note3) (Note4) 8VVIN40V, 0.5AILOAD3A Reference voltage VFB 1.193 1.230 1.267 V VOUT =5V RS2576-ADJ Efficiency VIN=12V, VOUT =5V, ILOAD=3A 77 % V1.1 4 August 2014 RS2576 ALL OUTPUT VOLTAGE VERSIONS ELECTRICAL CHARACTERISTICS Specifications with boldface type apply over for full operating temperature range, the other type are for T J=25℃ (Unless otherwise specified, VIN=12V, ILOAD=500mA) Parameter Symbol Test Condition Min. Typ. Max. Device Parameters Adjustable version only, VOUT Feedback bias current Ib 50 100 =5V Oscillator frequency Fo (Note 5) 47 52 58 Saturation voltage VSAT IOUT=3A (Note 6, 7) 1.5 1.8 (Note 7) 93 98 Max. duty cycle (ON) DC Min. duty cycle (OFF) (Note 8) 0 Current limit ICL Peak current (Note 6, 7) 3.5 4.5 5.5 Output=0V (Note 6, 8) 2.3 Output leakage current IL 7.5 Output=-1VV (Note 6, 8) 30 Quiescent current IQ (Note 8) 5 10 Standby quiescent current ISTBY ON/OFF pin=5V (Note 9) 50 200 θJC Thermal resistance TO263-5 θJA TO263-5 (Note 10) Unit nA KHz V % A mA mA μA Junction to case - 3.5 - ℃/W Junction to ambient - 30 - ℃/W ON/OFF Control ON/OFF pin logic input threshold voltage ON/OFF pin input current VIH VIL IIH IIL VOUT=0V VOUT=nominal output voltage VLOGIC=5V (Regulator OFF) VLOGIC=0V (Regulator ON) 2.0 - 4 0.01 0.6 30 10 V μA Notes: 1. Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. 2. External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator system performance. 3. Typical numbers are at 25℃ and represent the most likely norm. 4. The switching frequency is reduced when the second stage current limit is activated. 5. No diode, inductor or capacitor connected to output pin. 6. Feedback pin removed from output and connected to 0V to force the output transistor switch ON. 7. Feedback pin removed from output and connected to 12V to force the output transistor switch OFF. 8. VIN=40V. 9. Junction to ambient thermal resistance. (With copper area of approximately 3in 2) V1.1 5 August 2014 RS2576 CHARACTERISTICS CURVE V1.1 6 August 2014 RS2576 PACKAGE INFORMATION TO-263-5 Notes: 1. Refer to JEDEC TO-263 BA. 2. All dimensions are in millimeter. V1.1 7 August 2014 RS2576 IMPORTANT NOTICE Princeton Technology Corporation (PTC) reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and to discontinue any product without notice at any time. PTC cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a PTC product. No circuit patent licenses are implied. Princeton Technology Corp. 2F, 233-1, Baociao Road, Sindian Dist., New Taipei City 23145, Taiwan Tel: 886-2-66296288 Fax: 886-2-29174598 http://www.princeton.com.tw V1.1 8 August 2014