A8291

www.DataSheet4U.com A8291 Single LNB Supply and Control Voltage Regulator Features and Benefits ▪ 2-wire serial I2C™ -compatible interface: control (write) and status (read) ▪ LNB voltages (16 programmable levels) compatible with all common standards ▪ Tracking switch-mode power converter for lowest dissipation ▪ Integrated converter switches and current sensing ▪ Provides up to 500 mA load current ▪ Static current limit circuit allows full current at startup and 13→18 V output transition; reliably starts wide load range ▪ Push-pull output stage minimizes 13→18 V and 18→13 V output transition times for highly capacitive loads ▪ Adjustable rise/fall time via external timing capacitor ▪ Built-in tone oscillator, factory-trimmed to 22 kHz facilitates DiSEqC™ tone encoding, even at no-load ▪ Four methods of 22 kHz tone generation, via I2C™ data bits and/or external pin ▪ Filter bypass MOSFET minimizes losses during tone transmit ▪ 22 kHz tone detector facilitates DiSEqC™ 2.0 decoding ▪ Auxiliary modulation input ▪ LNB overcurrent with timer ▪ Diagnostics for output voltage level, input supply UVLO, and DiSEqC™ tone output ▪ Cable disconnect diagnostic Description Intended for analog and digital satellite receivers, this single low noise block converter regulator (LNBR) is a monolithic linear and switching voltage regulator, specifically designed to provide the power and the interface signals to an LNB down converter via coaxial cable. The A8291 requires few external components,...