Description
The ZLNB101 dual polarisation switch controller is one of a wide range of satellite receiver LNB support circuits. It features two completely independent channels, each providing two logic outputs under the control of a voltage sensitive input. It is intended for use in Twin LNB designs, replacing many dIscrete components to save both manufacturing cost and PCB size whilst improving reliability.
The two inputs of the ZLNB101 have a nominal threshold of 14.5V. Their 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.
Normal and an inverted outputs are provided for each input. All outputs can source 15mA and sink 10mA making them suitable to drive TTL and CMOS logic, pin diodes and for IF-amp supply switching.
The ZLNB101 operates from a single supply of between 5-12V. Its quiescent current is typically only 4mA and this does not change significantly with load or logic state. It is available in either the standard SO8 or space saving MSOP8 surface mount packages. Device operating temperature is -40°C to +85°C to suit a wide range of environmental conditions.
Universal LNB local oscillator selection is achieved by detection of a low level AC voltage superimposed on the polarisation control voltage. To facilitate this function, the ZLNB2012 includes a separate tone detector for each channel. Control of detector bandwidth and sensitivity is provided using an external resistor and capacitor for each channel. The tone detector has been designed give excellent rejection of low frequency control signals and DiSEqC™ tone bursts.
The ZLNB2012 has been specifically designed to minimise the solution cost whilst being flexible. The ZLNB2012 only requires two external components per channel to give full user control and functionality. The ZLNB2012 also includes complimentary outputs so that it can directly drive many multiplexer IC’s without the need of an inverter. Any unused outputs can be left open circuit without any effect to the remaining circuits operation Polarisation switch and tone detector outputs can directly drive TTL and CMOS logic, pin diodes, IF-amp supply switching and multiplexer IC’s.
The ZLNB2012 operates from a single supply which can be anything from 5-8V. Its quiescent current is typically only 9mA and this does not change significantly with load or logic state. It is available in the space saving QSOP16 surface mount package.
Feature(s)
Dual polarisation and tone switchReduced Cost Solution, only 2 external components per channelClose tolerance (14-14.5V) and temperature compensated polarisation switchMultiplexer IC direct driveTone and pol. Outputs are TTL, CMOS, Pin diode and IF amp capableTransient resistant inputsIncludes Receiver-Off detectorLow frequency and DiSEqC control signals rejectionEliminates many close tolerance discrete componentsWide supply operating rangeLow quiescent current
Application(s)
Twin Universal LNB’sQuad Universal LNB’sMulti Feed Universal LNB’sLNB switch boxes