AX3523 Datasheet | AXElite

1.5MHz, 0.8A Synchronous Step-Down Converter  GENERAL DESCRIPTION AX3523 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in an adjustable version. Supply current with no load is 250u A and drops to <1u A in shutdown. The 2.5V to 6V input voltage range makes AX3523 ideally suited for single Li-Ion, two to four AA battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications. Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and decreases need of an external schottky diode. Low output voltages are easily supported with the 0.6V feedback reference voltage. AX3523 is available in small TSOT-23-5L and TDFN-6L packages.  Features 2.5V to 6 V Input Voltage Range Output Voltage from 0.6V to VIN High Efficiency: Up to 95% 1.5MHz Constant Frequency Operation Up to 0.8A Output Current Quiescent Current: 250u A (Typical) No Schottky Diode Required Current Mode Operation for Excellent Line and Load Transient Response Current limit, Enable function Short Circuit Protect (SCP) Build in soft start function ≤ 1µA Shutdown Current TSOT-23-5L and TDFN-6L Pb-Free packages 1/9 Axelite Confidential Materials, do not copy or distribute without written consent. Rev.1.0 Apr. 13, 2011  BLOCK DIAGRAM VIN OSC REF 0.6V SET SLOPE P Isense AMP Soft-Star + RESET Ip + PWM LOGIC NON-OVERLAP CONTROL Over-Temperature and Short-Circuit Protection Enable Logic  PIN ASSIGNMENT The packages of AX3523 are TSOT-23-5L and TDFN-6L; the pin assignment is given by: Name EN VIN SW GND FB NC Description Enable pin H：normal operation L：Shutdown Power Supply Input Pin Switch output pin. Connect external...