Description

The AS7620 is an easy-to-use, high-efficiency, high-voltage, hysteretic step-down DC-DC converter, operating in asynchronous mode. Its low-power architecture extends hold-up time in battery-backed and critical applications where maximum up-time over a wide input supply voltage range is needed, while still providing for high efficiencies of up to 90% at 12V during peak current demands. Although the AS7620 is optimized for 24V applications found in industrial and medical systems, its ability to support 100% Duty Cycle makes the AS7620 ideal for applications demanding maximum up-time and soft power fail behavior. In combination with low idle current of only 30μA, on-demand switching reduces operating current at low load currents. By selecting an appropriate inductor value, operating current can be lowered and switching frequencies tuned to certain load conditions. A pin-strapped current limit input minimizes inductor peak current and thus inductor size and cost for any given application. The device further includes output short-circuit protection and thermal shutdown. In shutdown mode, only 1μA (typ) of current is consumed.

The AS7620 is available for 3.3V fixed output and adjustable output in a 12-pin 4x4 mm QFN package.

Key Features

• Input Voltage Range from 3.6V to 32V
• Output Voltage: 1.2 to Vin
• Output current: 500mA
• Dual Power Monitor
• 100% Duty Cycle
• Up to 90% Efficiency for 12V input
• Low 30µA quiescent current
• Pin-strapped Current Limit

Applications

• Utility Metering and Powerline Communications
• Signage Displays for Bus, Heavy Rail and Light Rail
• Industrial Automation
• Sensor Interfaces and Diagnostics
• 4-to-20mA Interfaces
• Portable Test Equipment

Block diagram for AS7620 Step-Down Converter IC

Block diagram for AS7620 Step-Down Converter IC