LA7780M Datasheet (Sanyo) - QPSK Downconverter

LA7780M, QPSK Downconverter

Pin No.

Function Pin voltage (V) Note Equivalent circuit 1 RF1 input 2.8 2 RF gain 1.3 Impedance connected to pin 2 must be > 45 Ω 3 GND 0 4 RF1 output Open collector 5 6 7 VCC VCC GND 5.0 5.0 0 8 9 RF2 input (1) RF2 input (2) 2.5 2.5 V = 2.5 V R = 1 kΩ 10 Internal/external AG

Ordering number : EN5268A Monolithic Linear IC LA7780M QPSK Downconverter for CATV Systems Overview The LA7780M is a downconverter for QPSK data demodulation for digital CATV transmission.

This IC integrates a preamplifier, an AGC amplifier, a mixer, an oscillator, a post-amplifier, and other circuits in a single chip, and provides all the functions required from cable signal input through output to the A/D converter.

Functions

LA7780M Features

* Since a preamplifier is built in, the LA7780M has adequate sensitivity to handle the input signal from the cable directly. (Input signal level:

* 30 to +30 dBm)

* Both internal and external AGC are supported as the AGC amplifier drive technique.

* The output amplitude