LNBP8

Intended for analog and digital satellite receivers, the LNBP8 is a monolithic linear voltage regulator, assembled in PowerFlexTM, specifically designed to provide the powering voltages and the interfacing signals to the LNB down-converter.

The regulator output can be logic controlled to be 13V or 18V (typ.) by mean of the VSEL pin for the remote controlling of the LNB. In order to reduce the power dissipation of the device when the lowest output voltage is selected, the regulator has 2 supply inputs (VCC1 and VCC2). They must be powered respectively at 15V (min.) and 22V (min.), and an internal switch will automatically select the appropriate supply voltage according to the selected output voltage.

The TONE pin (only for the LNBP9 version) activates the internal oscillator so that the DC output is modulated by a 22KHz square wave.

The LNBP8 is factory trimmed within a tolerance of +/- 2KHz, thus no further adjustment or external components are required. A burst coding of the 22KHz tone can be accomplished thanks to the fast response of the TONE input and the prompt oscillator start-up. This helps designers which want to implement the DiSEqCTM protocols.

In order to improve design flexibility and to allow implementation of other LNB remote control standards, an analogic modulation input pin (EXTM) is available (LNBP8 version only). An appropriate DC blocking capacitor must be used to couple the modulating signal source to the EXTM pin.

Both versions integrate thermal and short circuit protection.

The LNBP8 is packaged in PowerFlex for an easy thru-hole mounting. If an adequate Heatsink is provided and higher power losses are acceptable, both supply pins can be powered by the same 23V source without affecting any other circuit performance.

When the IC is powered and put in Stand-by (EN pin LOW), the regulator output is disabled and the IC power consumption is reduced to 300A typ.