SC14404 Complete Baseband Processor for DECT Handsets
PRELIMINARY
FEBRUARY 2000
SC14404
Complete Baseband Processor for DECT Handsets
General Description
The SC14404 is a CMOS chip optimized to handle all the
audio, signal and data processing needed within a DECT
handset. An ADPCM transcoder, a very low power CO-
DEC and Analog Frontend is integrated. Direct connec-
tions towards microphone and a (dynamical) loudspeaker
are provided. Duplex quality handsfree operation is inte-
grated.
The SC14404 is designed to fit to any radio design.
A dedicated TDMA controller handles all physical layer
slot formats and radio control.
National Semiconductors standard CompactRISC
TM
CR16B 16 bit microcontroller takes care of all the higher
protocol stack. 4 kilobyte F lash is integrated for parameter
and number storage.
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3V upto 5.0V battery monitor input.
Advanced battery management unit
Very low power in active and paging mode.
Embedded 16 bit CompactRISC
T M
Micro Controller.
(CR16B) with programmable clock speeds.
4k byte memory mapped Flash
320 kbyte Flash or factory programmed ROM FLASH.
ACCESSBUS
TM
or MICROWIRE
T M
interfaces
5,5 kilobyte on-chip Data Memory.
One full duplex ADPCM transcoder.
On-chip 14-bit linear CODEC.
14 upto 44 dB gain differential microphone input buffer.
100
鈩?/div>
loudspeaker driver.
Software controlled gain on audio input and output.
Peak hold ADC for RSSI measurement.
Five general purpose inputs can be multiplexed on an
8 bit ADC with selectable ranges.
On-chip dedicated TDMA instruction co-processor
which supports 1.152 MHz, 0.576 MHz and 0.288 MHz
bit rates.
Seven programmable control signals for radio front
end.
Full and double slot, protected and unprotected B-
fields.
Duplex quality handsfree operation.
Tone generator. Tones consisting of 3 frequencies can
be programmed
Linear PCM interface for external codec.
Features
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Integrated DECT Baseband transceiver optimized for
GAP handsets according to ETS 300 175-2, 175-3 &
175-8.
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Two on board low drop voltage regulators with 2.85V
and 3.0- 3.8V (with external resistors the voltage can be
determined) output.
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2V upto 3.6V battery input with onboard step up con-
verter.
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System Diagram
Note: ACCESSBUS
T M
, MICROWIRE
T M
and CompactRISC
T M
are trade-
marks of National Semiconductor Corporation.
Copyright 2000 National Semiconductor Corp.
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