The ARG81800 includes all control and protection circuits and is a PWM regulator with ±1.5% output voltage accuracy. With ultra-low static current, "no shutdown" power operation is achieved with minimal power current consumption during very light load stabilization. Available in 500mA and 1A versions, the ARG81800 can optimize the physical size of the power components for low-current systems, resulting in reduced PCB area and cost savings. PWM switching frequencies can be programmed over a wide range to balance optimization efficiency, component size, and EMC performance.
The ARG81800 can maintain the output voltage under no-load or very light load conditions in low power (LP) mode while drawing only microamperage current from the VIN. The ARG81800 includes a PWM/AUTO control pin, so the system can dynamically force PWM or AUTO modes by setting this pin to high or low, respectively. If the SYNCIN pin is driven by an external clock, the ARG81800 will be forced into PWM mode and synchronized with the input clock. The ARG81800 is able to add frequency jitter to the SYNCIN clock to reduce EMI/EMC. The ARG81800 features a CLKOUT pin, so the "downstream" regulator can be easily interleft and jitter with synchronous inputs.
The ARG81800 has external compensation, so it can be tuned with many different external components over a wide range of PWM frequencies to meet a wide range of system objectives. The ARG81800 includes an adjustable soft start that minimizes surge current. The ARG81800's extensive protection features include pulse-by-pulse current limiting, burp-mode short-circuit protection, start-open/short-circuit voltage protection, input undervoltage locking, output overvoltage protection, and thermal shut-off.
