DEVICE DESCRIPTION
The ZLNB2012 dual polarisation and tone switch controller is one of a wide range of satellite receiver LNB support circuits available from Zetex. It features two completely independent channels, each providing logic outputs to control LNB polarisation selection, local oscillator selection and downfeed disable. It is intended for use in Twin, Quad and multiple feed Universal LNBs, replacing many discrete components to save both manufacturing cost and PCB size whilst improving reliability.
The two highly accurate polarisation control inputs of the ZLNB2012 have a nominal threshold of 14.25V and to meet the required demanding needs from some broadcasters they have a switching range of 14.0V to 14.5V. The threshold is temperature compensated to minimise drift. Each features a low and stable input current that enables transient protection to be achieved with the addition of only a single resistor per channel.

FEATURES
● Dual polarisation and tone switch
● Reduced Cost Solution, only 2 external components per channel
● Close tolerance (14-14.5V) and temperature compensated polarisation switch
● Multiplexer IC direct drive
● Tone and pol. Outputs are TTL, CMOS, Pin diode and IF amp capable
● Transient resistant inputs
● Includes Receiver-Off detector
● User adjustable filter centre frequency and bandwidth
● Low frequency and DiSEqC control signals rejection
● Eliminates many close tolerance discrete components
● Wide supply operating range
● Low quiescent current

APPLICATIONS
● Twin Universal LNB’s
● Quad Universal LNB’s
● Multi Feed Universal LNB’s
● LNB switch boxes