TUA4300G Infineon Technologies Corporation, TUA4300G Datasheet - Page 5

• Manufacturer Part Number: TUA4300G
• Description: One Chip Car Radio, AM/FM Receiver
• Manufacturer: Infineon Technologies Corporation

FS: 04/93
3. AM - MODE
In the AM mode the 1st IF is converted by the 2nd mixer into the 2nd IF in the 450 kHz range. Therefore a 2nd LO,
which is used with quartz or as input for external sources, is part of the IC. An AGC in this mixer increases
sensitivity. The 2nd IF signal passes an automatic gain controlled IF amplifier and is then demodulated to the AF
in a quasisynchronous demodulator. Switching to seek mode, the AGC time constant is reduced by a factor of 5,
the 2nd mixer AGC is forced to high gain, the AM IF counter output is switched on and the AF is muted. The AGC
voltage is used as AM field strength and is fed to the combined field strength output.
SIEMENS AG
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HL DOK
V66047-S695-G100-G1
Circuit Description
TUA 4300 G
IC-SPECIFICATION
12.11.96
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