LGS5145 POWER CHIPS

The **Legend-Si LGS5145** is a high-efficiency, monolithic step-down (buck) DC-DC converter with integrated low RDS(on) 0.6 Ω high-side N-channel MOSFET, capable of delivering up to 1 A continuous output current. Featuring SKIP (pulse-frequency modulation) control mode, it combines ultra-low quiescent current with a high 1.2 MHz switching frequency to achieve excellent efficiency across a wide range of load conditions — from light load to full load.

**Key Specifications:**
– Brand: Legend-Si
– Part Number: LGS5145
– Topology: Non-synchronous buck (step-down)
– Input Voltage Range: 4.5 V to 55 V
– Output Voltage: Adjustable (via external feedback divider)
– Output Current: up to 1 A
– Integrated Switch: Built-in high-side N-MOSFET (RDS(on) = 0.6 Ω typ.)
– Switching Frequency: Fixed 1.2 MHz
– Quiescent Current (Iq): 150 µA (typ.)
– Control Mode: SKIP mode (PFM-like at light load for high efficiency)
– Operating Junction Temperature: –40 °C to +105 °C (TJ)
– Package: SOT-23-6
– Packaging: Tape & Reel

**Typical Applications:**
– Industrial and automotive 12 V / 24 V / 48 V power rails
– Wide-input battery-powered systems
– Distributed point-of-load regulation
– IoT devices, sensors, and edge nodes
– Telecom, networking, and instrumentation equipment
– General-purpose high-voltage buck conversion requiring compact size and high efficiency

The LGS5145 delivers outstanding light-load efficiency, wide VIN range, compact footprint, and robust performance in an ultra-small SOT-23-6 package — making it an ideal, cost-effective solution for space-constrained designs in industrial, automotive, and portable applications demanding low quiescent power and high input-voltage tolerance.