LM21305

Product Folder Sample & Buy Technical Documents Tools & Software Support & Community LM21305 SNVS639G – DECEMBER 2009 – REVISED DECEMBER 2015 LM21305 3-V to 18-V, 5-A, Adjustable Frequency Synchronous Buck Converter 1 Features 1 High-Efficiency Synchronous DC-DC Converter: – Integrated Low RDSon Power MOSFETs – Wide Input Voltage Range: 3 V to 18 V – Load Current as High as 5 A – Switching Frequency: 300 kHz to 1.5 MHz External Frequency Synchronization Accurate 0.598-V Feedback Voltage Reference Ultra-Fast Line and Load Transient Response: – Peak Current-Mode Control – Internal Slope Compensation – High-Bandwidth Error Amplifier Ultra-Low Shutdown Quiescent Current Wide Duty-Cycle Operating Range: – TON-MIN: 70 ns for Low VOUT – TOFF-MIN: 50 ns for High Duty Cycle Diode Emulation Mode at Light Loads Integrated Bias Supply LDO Sub-Regulators Internal Soft-Start Function: – Monotonic Startup into Pre-Biased Loads Precision Enable Input with Hysteresis Open-Drain PGOOD Indicator Internal Input Undervoltage Lockout (UVLO) Cycle-by-Cycle Overcurrent Protection Output Overvoltage Protection (OVP) Thermal Shutdown Protection with Hysteresis 5-mm x 5-mm WQFN-28 PowerPAD™ Package Typical Application Circuit VIN = 3V...18V CIN 10 F CFRQ SYNC RFRQ PVIN CBOOT AVIN EN SW LM21305 PGOOD FB FREQ 2V5 COMP 5V0 *VOUT tracks VIN if VIN < 3.4V CBOOT L VOUT = 3.3V 3.3 H RFB1 RFB2 COUT 47 F RC CC1 AGND PGND 2 Applications DC-DC Converters a...