•  4.2V to 18V Input Voltage Range
• Up to 2A Output Current
• Quiescent Current I_Q: 200 µA (typ.)
• Shutdown Current I_SHDN: 5 µA (typ.)
• Low R_DS(ON) for Internal Switches: 130mΩ Top, 105mΩ Bottom
• 500kHz Switching Frequency Minimizes Required External Components
•  Constant-On-Time and Ripple-Based Control
• Stable with 10µF C_OUT and 2.2µH Inductor
• Instant-PWM Architecture to Achieve Fast Transient Responses
• Cycle-by-Cycle Peak/Valley Current Limits
• Internal Soft-Start Limits the Inrush Current
• Hiccup Mode for Short-Circuit Protection
• Thermal Shutdown with Auto-Recovery
• Output Auto-Discharge Function
• RoHS-Compliant and Halogen-Free
•  Compact Package: SOT23-6

The SY21082 high-efficiency synchronous step-down DC/DC regulator operates over a wide input voltage range of 4.2V to 18V, and can deliver an output current up to 2A. It integrates a main switch and a synchronous switch with very low R_DS(ON) to minimize conduction loss. The 500kHz pseudo-constant switching frequency enables using small external inductor and capacitor values.

The SY21082 operates using Instant-PWM^TM architecture to achieve high efficiency at light loads  and fast transient response for applications with high step-down ratios. It also provides cycle-by-cycle current limiting and thermal shutdown protection.

The SY21082 is available in a SOT23-6 package.