A8293

The A8293 is designed for existing customer applications and should not be purchased for new design applications due to probable obsolescence in the near future. It features a 2-wire bidirectional serial interface compatible with the I2C™ standard, operating up to 400 kHz. The device is supplied in two lead (Pb) free MLP/QFN packages: ES, 20-contact, 4 mm × 4 mm, 0.75 nominal overall height, and ET, 28-contact, 5 mm × 5 mm, 0.90 nominal overall height. Some key features include a 2-wire serial I2C™-compatible interface for control and status, LNB voltages compatible with common standards, a tracking switch-mode power converter for low dissipation, integrated converter switches and current sensing, providing up to 700 mA load current, and a static current limit circuit allowing full current at startup and output transition. It also has a push-pull output stage, adjustable rise/fall time via external timing capacitor, built-in tone oscillator for DiSEqC™ tone encoding, and various methods of 22 kHz tone generation. The device also includes diagnostics for output voltage level and input supply UVLO.

The A8293's efficiency is enhanced by operating the boost converter at 352 kHz, which is 16 times the internal 22 kHz tone frequency. This allows for all loop compensation, current sensing, and slope compensation functions to be provided internally .

Some of the methods available for generating kHz tone signals in the A8293 for DiSEqC™ communications include four methods of 22 kHz tone generation via I2C™ data bits and/or external pin, built-in tone oscillator factory-trimmed to 22 kHz, and adjustable rise/fall time via external timing capacitor.