Overview

The LA1135 is a high-performance AM electronic tuner IC that is greatly improved in cross modulation characteristics. It is especially suited for use in car radio and home stereo (antenna: loop) applications.

Features

• Excellent cross modulation characteristics: Meets the requirements for preventing not only adjacent-channel interference but also interference caused by all channels within broadcast band.

• Narrow-band signal meter output: Usable as auto search stop signal. Has linearity up to 80 dBµ.

• Local oscillation buffer output: Facilitates designing of electronic tuner system, frequency display, etc.

• OSC (with ALC): Improves tracking error because oscillation output is stabilized at a low level (380 mVrms) for varactor diode.

• MIX: Double-balanced differential MIX meeting the requirements for preventing spurious interference, IF interference.

• Good characteristics at high input: 130 dBµ input fm= 400 Hz 80 mod THD = 0.4 typ

• Low noise: Good S/N at medium input (56 dB typ)

• Usable sensitivity: (S/N = 20 dB input): 25 dBµ (2SK315 IDSS = 11mA)

• VCC variation compensation: Less variation in gain, distortion: 8 to 12 V

• Reduced pop noise: Capable of reducing pop noise at the time of VCC ON, mode select by adjusting AGC time constant.

Functions

• MIX

• OSC (with ALC)

• IF amplifier

• Detector

• AGC (normal)

• RF wide-band AGC

• Auto search stop signal (signal meter output)

• Local oscillation buffer output

• Others