A8293SESTR-T A8293 A8293SES QFN 28

A8293 QFN28

Single LNB Supply and Control Voltage Regulator

voltage at the LNB pin is transitioning, the output voltage rise
and fall times can be set by the value of the capacitor connected
from the TCAP pin to GND (CTCAP or C7 in the Applications
Schematic). Note that during start-up, the BOOST pin is precharged to the input voltage minus a voltage drop. As a result,
the slew rate control for the BOOST pin occurs from this voltage.
The value of CTCAP can be calculated using the following formula:

▪ LNB voltages (8 programmable levels) compatible with
all common standards including domestic Japan models
▪ Tracking switch-mode power converter for lowest dissipation
▪ Integrated converter switches and current sensing
▪ Provides up to 700 mA load current
▪ Static current limit circuit allows full current at startup and
13→18V output transition; reliably starts wide load range
▪ Push-pull output stage minimizes 13→18V and 18→13V
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
▪ Auxiliary modulation input
▪ LNB overcurrent with timer
▪ Diagnostics for output voltage level, input supply UVLO