A8287

A8285 and A8287 LNB Supply and Control Voltage Regulator Features and Benefits LNB selection and standby function Provides up to 500 mA load current Two-wire serial I2C interface Built-in tone oscillator, factory-trimmed to 22 kHz; facilitates DiSEqC™ 2.0 encoding Auxiliary modulation input 22 kHz tone detector facilitates DiSEqC™ decoding (A8287 only) Tracking switch-mode power converter for lowest dissipation LNB overcurrent protection and diagnostics Internal overtemperature protection LNB voltages (16 possible levels) compatible with all common standards Packages 16-pin SOIC (A8285) 24-pin SOIC (A8287) Description Intended for analog and digital satellite receivers, the LNB (low noise block) converter regulator is a monolithic linear and switching voltage regulator, specifically designed to provide power and interface signals to an LNB downconverter, via coaxial cable. The device uses a 2-wire bidirectional serial interface, compatible with the I2C (Inter-C bus) standard, that operates up to 400 kHz. The A8285 is supplied in a 16-lead plastic power SOIC with internally fused leads for thermal dissipation. The A8287 is supplied in a 24-lead plastic power SOIC with internally fused leads. Both devices are also available in lead (Pb) free versions, with 100% matte tine leadframe plating. V IN C10 100 nF Functional Block Diagram C1 33 µF L1 33 µH D1 C5 100 nF C2 C4 100 nF 100 µF VREG C3 220 nF EXTM R3 R4 R5 VDD SDA SCL ADD IRQ VIN Internal Reg...