SY7088 Rev..pdf

Application Note: SY7088 2.3V Minimum Input and 5.5V Maximum Output 3A Peak Current Synchronous Boost with Output Disconnect Preliminary Specification AN_SY7088 Rev. 0.1A 1 General Description SY7088 is a high efficiency synchronous boost regulator that converts up to 5.5V output voltage. It adopts NMOS for the main switch and PMOS for the synchronous switch. It can disconnect the output from input during the shutdown mode. Ordering Information Package Code Temperature Code Optional Spec Code □(□□)□SY7088 Ordering Number Package type Note SY7088DGC DFN2x3-8 ---- Features ? 2.3-5.0V input voltage range ? Adjustable output voltage from 2.5V to 5.5V ? Pseudo-constant frequency: 1MHz ? 3A peak current limit ? Input under voltage lockout ? Load disconnect during shutdown ? Output over voltage protection ? Low RDS(ON) (main switch/synchronous switch) at 5.0V output: 70/100mohm ? Compact package: DFN2x3-8 Applications ? All Single Cell Li or Dual Cell Battery Operated Products as MP-3 Player, PDAs, and Other Portable Equipment. Typical Applications Figure 1. Schematic Diagram Figure 2. Efficiency Figure 昱灿电子?? SY7088 AN_SY7088 Rev. 0.1A 2 Pinout (top view) (DFN2x3-8) Top mark: VTxyz (Device code: VT, x=year code, y=week code, z= lot number code) Name DFN2x3-8 Description LX 1, 2 Inductor node. Connect an inductor between IN pin and LX pin. EN 3 Enable pin. Internal integrated with 1Mohm pull down resistor. SGND 4 Signal ground pin. FB 5 Feedback pin. Connect a resistor RH between OUT and FB, and a resistor RL between FB and GND to program the output voltage. VOUT=1.2V*(RH/RL+1). IN 6 Signal input pin. Decouple this pin to GND pin with at least 1.0uF ceramic cap for noise immunity consideration. OUT 7, 8 Power output pin. Decouple this pin to GND pin with at least 10uF ceramic cap. PG