Philips Semiconductors
Product specification
New In Car Entertainment (NICE) car radio
TEA6845AH; TEA6845H
1
FEATURES
• FM mixer for conversion of FM RF from 65 to 108 MHz
to IF of 10.7 MHz; the mixer provides inherent image
rejection
• FM RF mixer can be set to receive weather band radio
up to 162.55 MHz; weather band radio flag output
• Level detector for AM and FM with temperature
compensated output voltage; starting point and slope of
level output is programmable via the I2C-bus
• AM mixer 1 for conversion of AM RF to AM IF1 of
10.7 MHz
• LC tuner oscillator providing mixer frequencies for
FM mixer and AM mixer 1
• AM RF PIN diode drive circuit; AGC threshold detection
at AM mixer 1 and IF2 AGC input; threshold is
programmable via the I2C-bus; AM IF2 AGC and
demodulator
• AM mixer 2 for conversion of AM IF1 to AM IF2 of
450 kHz
• AM AF output switchable to provide AM IF2 for
AM stereo decoder
• Crystal oscillator providing mixer frequencies for
AM mixer 2 and reference for synthesizer PLL, IF count,
timing for Radio Data System (RDS) update and
reference frequency for car audio signal processor ICs
• AM noise blanker with blanking at AM IF2
• Several test modes available for fast IC and system
• Fast synthesizer PLL tuning system with local control for
tests.
inaudible RDS updating
• Timing function for RDS update algorithm and control
signal output for car audio signal processor ICs
(TEA688x, SAA77xx) or car radio integrated signal
processor IC (TEF6890H)
2
GENERAL DESCRIPTION
The TEA6845 is a single IC with car radio tuner for
AM and FM intended for microcontroller tuning with the
I2C-bus. It provides the following functions:
• Digital auto alignment circuit for conversion of
LC oscillator tuning voltage to controlled alignment
voltage of FM antenna tank circuit
• AM double conversion receiver for LW, MW and SW
(31 m, 41 m and 49 m bands) with IF1 = 10.7 MHz and
IF2 = 450 kHz
• AGC PIN diode drive circuit for FM RF AGC; AGC
detection at FM mixer input; the AGC PIN diode drive
can be activated by the I2C-bus as a local or distance
function; AGC threshold is a programmable and keyed
function switchable via the I2C-bus
• FM single conversion receiver with integrated image
rejection for IF = 10.7 MHz capable of selecting US FM,
US weather, Europe FM, East Europe FM and Japan
FM bands.
• FM IF linear amplifiers with high dynamic input range
• FM quadrature demodulator with automatic centre
frequency adjustment and Total Harmonic Distortion
(THD) compensation
3
ORDERING INFORMATION
TYPE
PACKAGE
NUMBER
NAME
DESCRIPTION
VERSION
TEA6845AH
QFP64
QFP64
plastic quad flat package; 64 leads (lead length 1.95 mm);
body 14 × 20 × 2.8 mm
SOT319-5
TEA6845H
plastic quad flat package; 64 leads (lead length 1.95 mm);
SOT319-2
body 14 × 20 × 2.8 mm
2001 Apr 12
3
NXP [ NXP ]
