Copyright 2001 National Semiconductor Corp.
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
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.
Features
I Integrated DECT Baseband transceiver optimized for
I Two on board low drop voltage regulators with 2.85V
I 2V upto 3.6V battery input with onboard step up con-
________________________________________________________________________________________________
System Diagram
Note: ACCESSBUS
GAP handsets according to ETS 300 175-2, 175-3 &
175-8.
and 3.0- 3.8V (with external resistors the voltage can be
determined) output.
verter.
TM
, MICROWIRE
SC14405
SC14405
SC14405
TM
and CompactRISC
SC14405
TM
SC14405
are trademarks of National Semiconductor Corporation.-
TM
1
SC14425
CID
Handsfree
I 3V upto 5.0V battery monitor input.
I Advanced battery management unit
I Very low power in active and paging mode.
I Embedded 16 bit CompactRISC
I 4k byte memory mapped Flash
I 128 kbyte Flash or factory programmed ROM FLASH.
I 125 segment LCD controller using 5 backplanes
I ACCESSBUS
I 5,5 kByte on-chip Data Memory.
I One full duplex ADPCM transcoder.
I On-chip 14-bit linear CODEC.
I 14 upto 44 dB gain differential microphone input buffer.
I 100
I Software controlled gain on audio input and output.
I Peak hold ADC for RSSI measurement.
I Five general purpose inputs can be multiplexed on an
I On-chip dedicated TDMA instruction co-processor
I 7programmable control signals for radio front end.
I Full and double slot, protected and unprotected B-
I Tone generator. 3 parallel tones can be programmed
I Linear PCM interface for external codec.
I Four general purpose ports. Three as input/output, one
(CR16B) with programmable clock speeds.
8 bit ADC with selectable ranges.
which supports 1.152 MHz, 0.576 MHz and 0.288 MHz
bit rates..
fields.Duplex quality handsfree operation.
as output only.
loudspeaker driver.
PSTN
Interface
ISDN or
Data
Interface
TM
or MICROWIRE
PSTN
ISDN
TM
TM
interfaces
Micro Controller.
APRIL 2001
www.national.com
V1.3