Description
Overview
The LA1235 is a high integrated IC developed for use in
high S/N, low distortion FM IF system applications. This
IC features S/N=88dB, distortion factor=0.015% and has
almost all functions required for FM tuner IF stage.
The IF amplifier and limiter stage consist of 6 stages of
double ended differential amplifier having an excellent
AMR, and this stage is followed by the signal meter driver
which consists of 4 stages of level detector, thereby
creating extended linearity up to strong input. The FM
detector stage consists of a double balanced quadrature
detector to which a low frequency pre amplifire and a
muting controller are attached. The muting drive stage
consists of an OR circuit for weak signal muting drive
output which detects signal intensity and detuning muting
drive output which detects S curve DC output and enables
the prevention of noise at the time of weak signal and
detuning. Further, the weak signal muting drive output
circuit contains a Schmitt circuit having hysteresis and
enables the prevention of muting malfunction due to
amplitude component at the time of weak signal. The AFC
output and tuning meter drive stage is of current drive type
which makes it possible to adjust AFC sensitivity and
muting band width by means of an external resistor, and
the built-in tuning meter null (short) circuit forces the
tuning meter to be [0] when the IF amplifier stops working.
The IF amplifier stop circuit, being a circuit to stop the FM
IF amplifier at the time of AM reception, makes it possible
to decrease shock noise due to FM-AM receiving mode
switchover.
Functions
• IF amplifier, Limiter.
• Quadrature detection.
• AF preamplifier.
• Signal intensity muting drive output.
• Detuning muting drive output.
• AF signal muting circuit.
• Signal meter drive output.
• AFC, tuning meter drive output.
• IF amplifier stop circuit.
• Tunig meter null circuit.
Features
• High S/N (88dB typ.).
• Low distortion (0.015% typ.).
• Weak signal muting drive output having hysteresis.
• Tuning mete null (short) circuit.
• Signal meter drive output having wide dynamic range.
• High limiting sensitivity.
• Built-in constant-voltage regulated circuit (Operating
voltage : 10 to 14V).
For full datasheet search…. Sanyo LA1235
These came to us as part of a lot of surplus stock from a large ‘Milspec’ type Co., having been in storage for some years we have classified them as ‘new other’. They are stored with us still sealed in their original packaging and are absolutely ‘as new’. You will receive your chip carefully repacked in a section of anti static tube.
SURPLUS STOCK ?????
If you have similar items to this, or indeed any electronic components that are surplus to requirements please contact us with details.
