Samsung MSYS 5200, Service Manual

Page: 70 / 210

S I G N A L PIN No. Type Description
Auxiliary Signals
T X ATT[3:1] 38, 39, 40 I Analog Transmit Attenuation.
The host can cause the modem to attenuate the transmit analog output in
steps of 2dB from 0dB by using the three encoded TXATT[3:1] inputs as
follows:
The TXATT[3:1] lines may be connected directly to 0V or 5V, or to three
GPIO lines used as outputs to select the attenuation under the host
program control.
BYPASS 36 I Receiver Highpass Filter Bypass Enable.
The state of this pin does not have any effect on the operation of the
modem, but it should tied to 5V or ground.
GP13, GP11 61, 63 I/O General Purpose I/O
GP[7:2] 5, 4, 3, 2 General Purpose Input/Output
1, 100
GP[21:19] 91, 93, 94 I General Purpose Input
GP[17:16] 76, 75
N C 19, 20, 27 Unbonded Pins (These are not connected to the internal logic)
28, 29, 31 No Connection
32, 33, 41
51, 62, 73
SYNCIN1 26 I Eye Sync Input 1, connect to SEPWCLK.
SYNCIN2 74 I Eye Sync Input 2, connect to SEPWCLK.
Analog Interface
V C 48 O Center Voltage. 2.5V output and it needs an external capacitor.
RCVI 37 I Transmitter Disable. When tied to “1”, it disables the transmitter side of
AFE.
R X A M P I 18 I Receiver Amplifier Input. This internally tied to pin17 which is Analog
Ground.
SWGAINI 24 I Externally connected to SWGAINI pin.
V R E F N 42 O Negative Reference Voltage
A O U T 49 O Externally connected to bypass capacitor to ground.
Analog Loopback Interface
A D I N 87 I Analog-to-digital Data In. 1-bit input to the internal decimation filter.
A D O U T 35 O Analog-to-digital Data Out. 1-bit input to the internal AFE’s RXPA TH.
D A I N 34 I Digital-to-analog Data In. 1-bit input to the internal AFE’s RXPA TH.
D A O U T 88 O Digital-to-analog Data Out. 1-bit output from the internal digital
interpolation filter.
Table 2-1 Hardware Interface Signal Descriptions (Cont.)
TXATT3 TXATT2 TXATT1 Attenuation (dB)
0 0 0 0
0 0 1 2
0 1 0 4
0 1 1 6
1 0 0 8
1 0 1 10
1 1 0 12
1 1 1 14
5-22 Samsung Electronics
Circuit Description