The PRX is a complete uninterruptable power management system on a single board. It combines an input power control unit with four battery chargers and a buck‐boost output regulator. When external power is present, the system automatically charges the battery pack(s) while supplying a regulated output voltage (which may be above, below, or equal to the battery voltage). When external power is removed, the system seamlessly switches to battery operation and continues to supply the regulated output voltage. When external power is restored, the system seamlessly reverts to input power and recharges the pack(s). When configured with multiple packs, the packs are all hot‐swappable.
The PRX displays its present status via five on‐board, bicolor LEDs. There is one LED for each battery pack and one for the overall system. For convenience, all the LEDs may be externally mirrored, and all status information can also be read electronically via an I2C link. Additionally, status information is broadcast periodically on an USART link (output only).
The PRX supports all common battery chemistries including lithium ion, lithium polymer, lithium iron phosphate, nickel metalhydride, nickel cadmium, and lead acid. Packs may be smart (SMBus) or dumb.