A8297SETTR-T

The A8297SETTR-T from Allegro Microsystems is a monolithic linear and switching voltage regulator specifically designed for analog and digital satellite receivers. It provides the necessary power and interface signals to an LNB down converter through a coaxial cable.

This device integrates a boost MOSFET, current sensing, and compensation circuitry, requiring few external components. It can supply up to 550 mA per channel continuously, or up to 700 mA per channel for reconfiguration, with a total continuous output of 950 mA and up to 1100 mA for reconfiguration. The adjustable LNB output current limit ranges from 300 mA to 800 mA.

Key features include 8 programmable LNB output voltage levels, an LNB overcurrent limiter with a shutdown timer, and a tracking boost converter to minimize power dissipation. It also incorporates a built-in 22 kHz tone oscillator for DiSEqC™ tone encoding, which does not require additional external components. The device includes extensive protection features such as UVLO, OCP, TSD, and CPOK.

The A8297SETTR-T utilizes a 2-wire bidirectional serial interface, compatible with the I2C™ standard, operating up to 400 kHz. It is supplied in a small, low-profile 28-QFN (5x5 mm) package, suitable for surface mounting. The operating temperature range is -20°C to 85°C.