LOW POWER 4 STAGE FET BIAS CONTROLLER
DESCRIPTION
The UTC L8402 is designed to bias the MOSFETs that are commonly used in LNBs that can implies minimum external components requires. The UTC L8402, provide four FETs bias control respectively. By adjusting two external resistors, it can change the FET’s bias current to optimize the satellite receiver front end block performances. As an additional feature the Rcal pins can also be used as logic inputs to disable pairs of FETs as part of a power management scheme or simply an alternative to LNA switching. Driven to a logic high (>3.0V), the inputs disable their associated FET bias stages by switching gate feeds to 2.5V and drain feeds open circuit. It generates the required negative voltage to bias the gate of FETs, and internally provides protection circuit that can protect the FET devices during supply voltage transient. So it is very popular in satellite receiver front end block.
FEATURES
* Can Bias up to 4 FETs
* Wide supply voltage range: 3V~8V
* Low quiescent supply current, 1mA typical
* FET drain voltages set at 2.0V
* Adjustable FET device operating current
* FET drain voltages and currents held stable over temperature and VCC variations
* Built in FET device protection circuit
* Low external component count
