2003 Oct 21 3
Philips Semiconductors Product specification
Car radio integrated signal processor TEF6894H
1 FEATURES
1.1 General
• High integration
• No external components except coupling capacitors for
signal inputs and outputs
• QFP44 package with small Printed-Circuit Board (PCB)
footprint.
1.2 I
2
C-bus
• Fast mode 400 kHz I
2
C-bus, interfaces to logic levels
ranging from 2.5 to 5 V
• Gated I
2
C-bus loop through to tuner IC
– Eases PCB layout (crosstalk)
– Allows mix of 400 kHz and 100 kHz busses
– Low bus load reduces crosstalk
– Buffered I/O circuit
– Supply voltage shift between both buses allowed.
• Shortgate function offers easy control with automatic
gating of a single transmission; suited for TEA684x
• Autogate function offers transparent microcontroller
control with automatic on/off gating (programmable
address).
1.3 Stereo decoder
• FM stereo decoder with high immunity to birdy noise and
excellent pilot cancellation
• Integrated IF roll-off correction controlled via I
2
C-bus
• De-emphasis selectable between 75 and 50 µs via
I
2
C-bus.
1.4 Noise blanking
• New fully integrated AM noise blanker with excellent
performance
• Fully integrated FM noise blanker with superior
performance.
1.5 Weak signal processing
• FM weak signal processing with detectors for RF level,
Ultrasonic Noise (USN) and Wideband AM (WAM)
information
• AM weak signal processing with detectors for level
information
• AM processing with soft mute and High Cut Control
(HCC)
• FM processing with soft mute, stereo blend and HCC
• Setting of the sensitivity of the detectors and start and
slope of the control functions via I
2
C-bus
• Weather band de-emphasis
• Level, USN and WAM read-out via I
2
C-bus (signal
quality detectors)
• Full support of tuner AF update functions with TEA684x
tuner ICs, FM audio processing holds the detectors for
the FM weak signal processing in their present state
during RDS updating.