Allegro Microsystems ARG81800

Description

The ARG81800 includes all the control and protection circuitry to produce a PWM regulator with ±1.5% output voltage accuracy, with ultralow quiescent current to enable “keepalive” supply operation with minimal current draw from the supply during very light load regulation. There are two versions of the ARG81800 available, 500 mA and 1 A, so the physical size of the power components can be optimized for lower current systems, thus reducing PCB area and saving cost. PWM switching frequency can be programmed over a wide range to balance efficiency, component sizing, and EMC performance. If VIN decays and the duty cycle reaches its maximum, the ARG81800 will automatically fold back its PWM frequency to extend the duty cycle and maintain VOUT.

Features

• Automotive AEC-Q100 qualified
• Input operating voltage range: 3.5 to 36 V
• Withstands surge voltages to 40 V for load dump
• Low-Power (LP) mode—draws just 8 μA from VIN while maintaining 3.3 or 5.0 VOUT
• AUTO mode allows automatic transition between PWM and LP mode based on load current
• Programmable PWM frequency (fSW): 250 kHz to 2.4 MHz
• PWM frequency dithering and controlled switch node slew rate reduce EMI/EMC signature
• CLKOUT allows interleaving and dithering of “downstream” regulators using their synchronization inputs
• Interleaving minimizes input filter capacitor requirement and improves EMI/EMC performance
• Synchronization of PWM frequency to external clock on SYNCIN pin
• Adjustable output voltage: ±1.5% accuracy over operating temperature range (‒40°C to 150°C)
• Maximized duty cycle at low VIN improves dropout
• Soft recovery from dropout condition
• Adjustable soft-start time controls inrush current to accommodate a wide range of output capacitances
• External compensation provides flexibility to tune the system for maximum stability or fast transient response

Typical applications

• Industrial Systems
• Home Audio, Audio Systems, HVAC Systems
• Infotainment, Navigation Systems, Instrument Clusters, ADAS Applications
• Network and Telecom
• Battery Powered Systems

More information

• Datasheet