SC14405 Complete Baseband Processor for DECT Handsets
APRIL 2001
V1.3
SC14405
Complete Baseband Processor for DECT Handsets with on-
chip Flash and LCD controller
General Description
The SC14405 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 SC14405 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 kByte Flash is integrated for parameter
and number storage.
The SC14405 has an 125 segment LCD controller.
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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
TM
Micro Controller.
(CR16B) with programmable clock speeds.
4k byte memory mapped Flash
128 kbyte Flash or factory programmed ROM FLASH.
125 segment LCD controller using 5 backplanes
ACCESSBUS
TM
or MICROWIRE
TM
interfaces
5,5 kByte 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..
7programmable control signals for radio front end.
Full and double slot, protected and unprotected B-
fields.Duplex quality handsfree operation.
Tone generator. 3 parallel tones can be programmed
Linear PCM interface for external codec.
Four general purpose ports. Three as input/output, one
as output only.
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.
________________________________________________________________________________________________
System Diagram
SC14405
SC14405
ISDN or
Data
Interface
ISDN
SC14425
CID
Handsfree
PSTN
Interface
PSTN
SC14405
SC14405
SC14405
Note: ACCESSBUS
TM
, MICROWIRE
TM
and CompactRISC
TM
are trademarks of National Semiconductor Corporation.-
Copyright 2001 National Semiconductor Corp.
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www.national.com
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