Motorola Internal Use
4
P7389i – Circuit Description
13)
The signal is then passed to the new
MAGIC DM DM IC U200
PRE IN
Pin A7
(
M
ultiple
A
ccumulator
G
SM
I
C
D
ual
M
ode)
14)
The signal is then demodulated internally using an external 800 MHz Varactor diode
CR249
,
RX Local Oscillator set up, which is driven by
PLL CP
Pin E9
of
MAGIC
DM U200
.
15)
Where in earlier products, we used to have
RX RXQ, and I
these signals are now
only used in digital form within the MAGIC DM and can only be measured using a
specific set up. The demodulated signal is now converted internally to a base band
digital form to be passed along an RX SPI bus to the Whitecap.
16)
The
RX SPI
signal is made up of
BDR
(Base band Data Receive),
BFSR
(Base band
Frame Synch Receive) and
BCLKR
(Base band Clock Receive, fed from MAGIC
DM
Pins G8, G9 and F7
respectively.
17)
If internal signal GPRS_TX is high the base band data signal
BDR
will be converted
from a 2’s compliment 8 bit data word to a 10 bit data word
I.e.
Normal Mode
:
8 I bits, 8 Q bits, 32 zeros
GPRS Mode
:
10 I bits, 6 zeros, SDFS pulse, 10 Q bits, 6 zeros (16 idle bit times)
18)
The new
SPS ROM 6
Whitecap U800
receives these signals on
Pins A3, D4 and B4,
within the Whitecap the signal is digitally processed. Baud rate reduced, Error
correction bits removed, deciphered and de-interleaved.
19)
The digital signal is now being fed down the
DIG_AUD_SPI
bus to the
GCAP II
U900
, internally to the GCAP, the digital signal is converted to analogue and
distributed to the correct outputs:
20)
For Earpiece speaker, from GCAP II
Pins H6 and H7
to speaker pads
J502
and
J503
21)
The Alert is generated within the Whitecap, given the appropriate data from the
incoming signal, SMS, call etc… and is fed to the alert pads
J5003
and
J5004
. This
signal is supported by the signal
ALRT_VCC
, which is generated from B+ through
Q903
.
22)
For the headset only the
SPKR-
signal is used from GCAP II
Pin H6
.The output is
then fed out to the
Headset Jack socket J504.
Pin 3.
RF:
Transmit
1)
There are 2 Mic inputs, firstly from the
Xcvr Mic J900
, where the analogue input is
fed to the
GCAP II U900
Pin J2.
2)
Secondly the analogue voice can be fed from the Aux Mic attached to the headset and
will be routed from
connection 5
of the
Headset Jack J504
, through to GCAP II,
Pin