LT1946

LT1946 1.2MHz Boost DC/DC Converter with 1.5A Switch and Soft-Start FEATURES s s s s s s s DESCRIPTIO 1.5A, 36V Internal Switch 1.2MHz Switching Frequency Integrated Soft-Start Function Output Voltage Up to 34V Low VCESAT Switch: 300mV at 1.5A (Typ) 8V at 430mA from a 3.3V Input Small 8-Lead MSOP Package U APPLICATIO S s s s s TFT-LCD Bias Supplies GPS Receivers DSL Modems Local Power Supplies The LT®1946 is a fixed frequency step-up DC/DC converter containing an internal 1.5A, 36V switch. Capable of generating 8V at 430mA from a 3.3V input, the LT1946 is ideal for large TFT-LCD panel power supplies. The LT1946 switches at 1.2MHz, allowing the use of tiny, low profile inductors and low value ceramic capacitors. Loop compensation can be either internal or external, giving the user flexibility in setting loop compensation and allowing optimized transient response with low ESR ceramic output capacitors. Soft-start is controlled with an external capacitor, which determines the input current ramp rate during start-up. The 8-lead MSOP package and high switching frequency ensure a low profile overall solution less than 1.2mm high. , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO VIN 3.3V 3 1 L1 4.7µH 6 VIN SHDN LT1946 VC SS CSS 100nF 8 7 FB COMP GND 4 OFF ON C1 2.2µF RC 49.9k CC 470pF 5 SW D1 90 VOUT 8V 430mA 85 80 EFFICIENCY (%) R1 28.7k 2 R2 5.23k C2 20µF 75 70 65 60 55 C1: 2.2µF, X5R OR X7R, 6.3V C2: 2 × 10µF, X5R OR X7R, 1...