Switching Voltage Regulators Power LNB Downconverters Via Coax

Fully integrated linear and switching voltage regulators developed by Allegro MicroSystems supply the power and interface signal to low-noise block (LNB) downconverters through a coaxial cable. The “Generation 5” A8300 and A8300-1 are optimized for low-profile ceramic boost capacitors and lower-cost electrolytic capacitors, respectively. For DiSEqC communication, the ICs provide an internal 22-kHz tone that’s gated with a control pin, or accept an external 22-kHz tone through the same pin. Integrated tone-detection capability enables full two-way DiSEqC communications. There’s also an integrated gate drive for the filter bypass FET. A power-saving “sleep” pin quickly shuts down the device if needed without using I²C control, and an Early Power Failure (EPF) function helps verify the status of the 12-V rail as well as initiates shutdown routines. Packaging is a 4- by 4-mm, 24-contact lead-free QFN with tin-plated leadframe.

ALLEGRO MICROSYSTEMS LLC