TEF6862

· High dynamic range FM front-end mixer for conversion of FM RF (65 MHz to 108 MHz and USA weather band) to an IF frequency of 10.7 MHz; mixer provides inherent image rejection which can be switched from low injection LO to high injection LO via the I2C-bus
· FM front-end AGC PIN diode drive circuit; AGC detection at the FM font-end mixer input and the IF filter input; AGC threshold for detection at the mixer input is programmable and keyed AGC function can be selected via the I2C-bus; the AGC PIN diode drive can be activated by the I2C-bus for a search tuning in local mode; in AM mode the AGC PIN diode drive can be activated by the I2C-bus if required;information on amount of PIN diode AGC is available via the I²C-bus
· FM front-end mixer includes +6 dB gain setting via the I2C-bus
· FM second mixer for conversion of IF1 10.7 MHz to IF2 450 kHz including inherent image rejection; the gain can be controlled via the I2C-bus
· Integrated FM channel selection filter with continuous variable bandwidth providing simultaneous low distortion and high selectivity with only one external ceramic filter;improved sensitivity with dynamic threshold extension can be enabled via the I2C-bus
· Fully integrated FM demodulator with very low distortion
· Digital bandwidth control algorithm with detection on adjacent channel information,deviation, detuning and level with customer flexibility via the I2C-bus
· Digital alignment circuit for bus controlled adjustment of oscillator tuning voltage to two FM antenna tank circuit tuning voltages; AM and FM level start and slope alignment;IF filter and demodulator center frequency alignment
· AM and FM level detection (signal strength indication)
· Separate RF input to FM front-end mixer for weather band
· Flag or voltage output indicators for actual IF bandwidth information
· AM front-end mixer for conversion of AM RF to an IF frequency of 10.7 MHz
· AM RF AGC circuit for external cascode AGC and PIN diode AGC
· AM noise blanker with detection at IF1 and blanking at IF2
· AM second mixer for conversion of IF1 10.7 MHz to IF2 450 kHz; IF2 AGC amplifier and AM demodulator with low distortion
· For AM stereo applications the gain controlled AM IF2 output voltage can be switched to MPXAM output pin via the I2C-bus
· Crystal oscillator providing frequency for second conversion, references for synthesizer PLL and analog signal processor and timing for tuning action
· LC tuning oscillator with low phase noise and oscillator dividers with selectable divider ratios for worldwide tuner reception without band switching in application
· Fast synthesizer PLL tuning system with dynamically adapting loop parameters combining fast PLL frequency jumps for inaudible RDS updating with low spurious responses for large signal-to-noise ratios
· Sequential state machine for preset change, search and inaudible AFU allowing a timing uncritical microcontroller operation; the state machine generates timing signals for the internal inaudible tuning mute and analog or digital signal processor
· An alternative frequency check can be initiated by the signal processor for audio correlation algorithms directly without involvement of the microcontroller
· Audio soft slope tuning mute circuit allowing inaudible AFU
· Two hardware programmable I²C-bus addresses
· Two software controlled flag outputs
· Several test modes for fast IC and system tests

The TEF6862 is a single-chip car radio tuner for AM, FM and weather band reception providing AM double conversion for LW, MW and full range SW (11 m to 120 m bands) with IF1 = 10.7 MHz and IF2 = 450 kHz.

FM double conversion to IF1 = 10.7 MHz and IF2 = 450 kHz with integrated image rejection for both IF1 and IF2; integrated IF filter with variable bandwidth and automatic bandwidth control algorithm with flexibility via the I²C-bus; capable of US FM, Europe FM,Japan FM, East Europe FM and weather band reception; all FM bands can be selected using high injection LO or low injection LO in the FM mixer 1.

Tuning system including crystal oscillator, VCO, PLL synthesizer and state machine for timing uncritical control of search, preset change and AF check via microcontroller.