The TPS6521855 provides three step-down converters, three load switches, three general-purpose I/Os, two battery backup supplies, one buck-boost converter, and one LDO. The system can be supplied by a regulated 5-V supply. The device is characterized across a –40°C to +105°C temperature range, which makes it suitable for various industrial applications.

The I²C interface provides comprehensive features for using TPS6521855. All rails, load switches , and GPIOs can be enabled and disabled. Voltage thresholds for the UVLO and supervisor can be customized. Power-up and power-down sequences can also be programmed through I²C. Interrupts for overtemperature, overcurrent, and undervoltage can be monitored for the load-switches (LSx).

The integrated voltage supervisor monitors DCDC 1-4 and LDO1. It has two settings; the standard settings only monitor for undervoltage, while the strict settings implement tight tolerances on both undervoltage and overvoltage. A power-good signal is provided to report the regulation state of the five rails.

The three hysteretic step-down converters can each supply up to 1.8 A of current. The default output voltages for each converter can be adjusted through the I²C interface. DCDC1 and DCDC2 features dynamic voltage scaling with an adjustable slew rate. The step-down converters operate in a low power mode at light load, and can be forced into power mode (PWM) operation for noise sensitive applications.

The battery backup supplies consist of two low power step-down converters optimized for very light loads and are monitored with a separate power-good signal (PGOOD_BU). The converters can be configured to operate as always-on supplies with the addition of a coin cell battery. The state of the battery can be monitored over I²C.