AN84 [SILICON]
DIGITAL HYBRID WITH THE Si305X DAAS; WITH THE Si305X DAAS数字混合
| 型号： | AN84 |
| 厂家： | 
SILICON |
| 描述： | DIGITAL HYBRID WITH THE Si305X DAAS |
| 文件： | 总26页 (文件大小：989K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
AN84
DIGITAL HYBRID WITH THE Si305X DAAS
1. Introduction
Z-4
b0
This application note is a guide to understanding and
implementing the digital hybrid feature found in Si305x
DAA products. The Si305x contains an on-chip analog
hybrid that performs the 2- to 4-wire conversion and
near-end echo cancellation. This hybrid circuit is
adjusted for each ac termination setting selected to
achieve a minimum transhybrid balance of 20 dB. The
Z-1
b1
+
Z-1
Si305x also offers a digital filter for additional near-end
echo cancellation to compensate for any line
impedance mismatch. For each ac termination setting,
the eight programmable hybrid registers (Registers 45-
52) can be programmed with coefficients to increase the
Z-1
cancellation under real-world line conditions. This digital
filter can produce 10 dB or greater of near-end echo
cancellation in addition to the 20 dB from the analog
hybrid circuitry.
b7
1.1. Digital Hybrid Overview
Figure 1. Digital Hybrid Structure
Figure 1 describes the basic architecture of the digital
hybrid. It is composed of an 8-tap FIR filter. “b0” through
“b7” represent the filter coefficients in 2s complement
form. The initial 4-sample bulk delay is used to
compensate for the round trip delay through the line-
side device. This architecture is designed to delay and
filter the transmit signal to match the portion not
cancelled by the analog hybrid.
Figure 2 illustrates the basic signal flow of the DAA. The
digital signal has been upsampled to 16 kHz at the
digital hybrid stage. The transmit signal goes through a
digital filter, digital-to-analog converter, and analog filter
before going out on the line or being used in the analog
hybrid circuitry. After the analog hybrid, the receive
signal passes through an analog filter, analog-to-digital
converter, and digital filter before going back into the
digital hybrid. The analog hybrid path adds
approximately four samples of delay to the signal. The
digital hybrid structure matches this filter delay by
delaying the digital samples by the same amount.
AC
Termination
Line Driver
Analog
Filters
Digital
Filters
TX
DAC
ADC
Line
Digital
Hybrid
@16kHz
Analog
Filters
Analog
Hybrid
Digital
Filters
RX
Figure 2. Signal Flow Diagram
Rev. 0.6 6/07
Copyright © 2007 by Silicon Laboratories
AN84
AN84
DAC
at 16 kHz
TX
HT(ω)
HR(ω)
HL(ω)
HD(ejω)
at 16 kHz
-
+
+
ADC at
16 kHz
+
+
RX
+
Figure 3. Model
A model of the DAA and the phone line is shown in Substituting for H (ω) in the equation results in:
L
Figure 3. In an ideal system, the analog hybrid yields
perfect cancellation of the near-end echo from the
ZLine
ZLine + ZACT
ZLine – ZACT
ZLine + ZACT
transmit path. A mismatch between the ac termination
and the load produces an echo that is not removed by
the analog hybrid. To increase the near-end echo
cancellation, the digital hybrid must equalize the
disparity between the impedance mismatch of the ac
termination and the line.
---------------------------------
---------------------------------
– 1 =
HL – 1 = 2 ×
If Z
and Z
are matched, the analog hybrid
ACT
perfectly cancels the transmit signal.
LINE
Substituting this result into the echo equation yields:
From the above model, the echo is equal to:
ZLine – ZACT
ZLine + ZACT
---------------------------------
echo = HT(ω) × HR(ω)
echo = HT(ω) × HL(ω) × HR(ω) – HT(ω) × HR(ω)
= HT(ω) × HR(ω)[HL(ω) – 1]
The model for the H (ω) and H (ω) plays a critical role
T
R
in this calculation. The models are quite complex, and
sampled data of the models are necessary to calculate
the hybrid coefficients. Contact Silicon Labs to acquire
the sampled data of the H (ω) and H (ω) models.
H (ω) consists of the DAA’s ac termination in
L
combination with the impedance of the twisted pair
transmission line terminated at the central office (CO)
by a reference impedance. Figure 4 shows the analog
T
R
A group delay, which was not illustrated in the model,
must also be taken into consideration. Internal DSP and
filters cause this delay. Taking the group delay into
account, the echo is equal to:
hybrid circuitry and the H (ω) model expanded to
include the ac termination and line.
L
ZACT
2
j2π
⎛
⎞
----------------
× gd
⎠
echo = H (ω) × HR(ω) × [HL(ω) – 1]e⎝16000
T
where gd is the group delay.
ZLINE
The digital hybrid must cancel the echo by intentionally
-
+
adding the negative of the echo. The H (ω) should be:
D
+
j2π
⎛
⎞
----------------
× gd
⎠
HD(ω) = –H (ω) × H (ω) × [HL(ω) – 1]e⎝16000
R
T
Figure 4. HL(ω)–1 Model
2
Rev. 0.6
AN84
To use the Digital Hybrid Calculation Tool, simply enter
the ACIM value recommended in Table 13 of the Si3050
datasheet into the ACIM control. This value determines
the impedance presented by the DAA to the line. It is
governed by the region in which the application will be
deployed. Next, enter values for R1 and R2 in ohms and
C in farads into the appropriate controls. These values
will represent the impedance presented by the central
office to the line. This value is also governed by the
region in which the application will be deployed. Also,
select the line-side device used in the application in the
pull-down box. Finally, select the line model to be used
that will most closely model the line connecting the DAA
to the central office. This is done by either picking a
specific EIA line model or by specifying a wire gauge
and length. Once this is complete, hitting the
"CALCULATE" button will generate the coefficients that
provide the best performance.
1.2. Digital Hybrid Calculation Tool
Silicon Labs has developed a useful graphical user
interface tool (shown in Figure 5) that will assist in
calculating the coefficients to use with the digital hybrid
in the Si305x DAA product family. The tool allows the
user to enter the reference termination of the central
office (in an R + R||C format) and the model for the
phone line between the DAA and the central office. The
line can be represented by one of the EIA models,
shown in " Appendix C—EIA Line Models" on page 24,
or as a specified length of wire. The software then
executes the Matlab code found in " Appendix A—
Sample MATLAB Code" on page 7, which graphically
shows the expected trans-hybrid response of the digital
hybrid and lists the best hybrid coefficients to use given
the line characteristics.
Three graphs are shown in Figure 6. An echo graph is
created by intentionally mismatching the 600 Ω ac
termination with the TBR21 mode CO termination. The
digital hybrid response is the 8-tap FIR filter response
calculated using the sample code found in Appendix A.
The cancelled graph is obtained by adding the echo and
the digital hybrid response. The digital hybrid response
looks very similar to an echo. Figure 7 shows the phase
of the echo and the digital hybrid response. The phase
of an echo and the digital hybrid have the opposite
polarity. Figure 8 compares the rejection in dB with and
without the digital hybrid. By properly using the digital
hybrid, near-end echo cancellation has increased by
approximately 20 dB.
For example, if we assume that an application will be
deployed within the U.S., we enter a 0 for the ACIM
value. Also, the central office impedance in the US is
900 Ω in series with 2.16 µF. To enter this information in
the GUI, we enter 900 for R1 and a fairly large value for
R2, since it is not present. For this example, the value of
100,000 Ω was used. For the C value, we enter 2.16e-6
since the expected units are farads. Also, for this
example, we use an EIA model of 0. This means
essentially no loop length, and the central office
impedance is connected directly to the application. Now,
the "CALCULATE" button is pressed, and the resulting
coefficients, 0xF8, 0xF9, 0x03, 0xFE, 0xFE, 0x00,
0xFE, and 0x00, are generated.
Rev. 0.6
3
AN84
Figure 5. Digital Hybrid
4
Rev. 0.6
AN84
To generate the coefficients, the 8-tap FIR filter
structure used in the digital hybrid must be taken into
account. This digital filter structure requires the hybrid
response to be represented in the z-domain.
1.3. Conclusion
The Si305x DAA product family is designed to increase
the near-echo cancellation with an additional hybrid in
the digital path operating at 16 kHz. Near-end echo is
primarily caused by the mismatch between the ac
termination and the CO termination. The transmit and
receive signal path also affects the echo to a lesser
extent. By introducing a filter that models the near-end
“Appendix A—Sample MATLAB Code” contains sample
MATLAB code to calculate the hybrid coefficients. This
code should help in understanding the process of
calculating the hybrid coefficients.
echo 180 degrees out-of-phase to the receive path A hybrid coefficient lookup table can be found in
echo, the hybrid response can be improved. This " Appendix B—Hybrid Coefficient Lookup Tables" on
improvement in the hybrid response results in greater page 10. These tables provide a set of coefficients to
cancellation of the transmit signal when the near-end use for different line conditions.
echo and digital hybrid response are added together at
the digital hybrid stage.
Figure 6. Echo
Rev. 0.6
5
AN84
Figure 7. Echo Phase
Figure 8. Rejection
6
Rev. 0.6
AN84
APPENDIX A—SAMPLE MATLAB CODE
A sample MATLAB program for use in setting the hybrid coefficients is shown below. The code takes the ACIM
(Register 30) setting and line model as an input and outputs the best coefficient for the digital hybrid to match the
line.
function hdh
HrPhase);
=
dig_hybrid(ACIM, R1line, R2line, Cline, HtMag, HtPhase, HrMag,
% hdh = dig_hybrid(ACIM, R1line, R2line, Cline, HtMag, HtPhase, HrMag, HrPhase);
%
% This function calculates the coefficient values for the digital
% hybrid given a R1+R2||C model for the line.
%
% ACIM : register setting of the AC termination
% R1line : line R1
% R2line : line R2
% Cline : line C
% HtMag : Transmit path response
% HtPhase : Transmit path response
% HrMag : Receive path response
% HrPhase : Receive path response
%
% hdh : digital hybrid coefficients
Nact=ACIM+1;
if(R1line==0), R1line=eps; end
if(R2line==0), R2line=eps; end
if(Cline==0), Cline=eps; end
%eps is the smallest value after 0
% Set sample rate and frequency grid
fs=16000;
f=[eps:1:7999];
w=2*pi*f/fs;
%%%%%% Transmit path (Ht)
Ht = HtMag .* exp(j*HtPhase)
%%%%%%%
Receive path (Hr)
Hr = HrMag .* exp(j*HrPhase)
Rev. 0.6
7
AN84
%%%%%%%%%% Near end echo (H2)
% Calculate Zline
Zcline=1./(j*2*pi*f*Cline);
Zline=R1line + R2line.*Zcline./(R2line+Zcline);
% Calculate Zref, assume perfect ACT
R1ref=[eps eps 270 220 370 320 370 275 120 350 eps 600 900 900 600 270];
R2ref=[600 900 750 820 620 1050 820 780 820 1000 900 1e9 1e9 1e9 1e9 750];
Cref =[eps eps 150 117 310 230 110 132 110 210 30 2160 1000 2160 1000 150]*1e-9;
Zcact=1./(j*2*pi*f*Cref(Nact));
Zact=R1ref(Nact) + R2ref(Nact).*Zcact./(R2ref(Nact)+Zcact);
C9r=0*1e-9;
Ycact2=(j*2*pi*f*C9r);
Zact=1./(1./Zact + Ycact2);
%%%%%
HL=2*Zline./(Zact+Zline);
HL(1)=0;
% Add extra group delay to match measurements
gde=-0.225;
Hd=-Ht.*Hr.*(HL-1).*exp(j*2*pi/16000*gde*[0:length(Ht)-1]);
Hd=[Hd conj(fliplr(Hd))];
% Estimate impulse response to match
hd=real(ifft(Hd));
% Truncate coefficients and express in [0 255]
hdh=round(hd(5:12)*64);
ind=find(hdh<0);
hdh(ind)=hdh(ind)+256;
echo = Ht.*Hr.*(HL-1).*exp(j*2*pi/16000*gde*[0:length(Ht)-1]);
hyb_coef = [0 0 0 0 hd(5:12)];
dig_hyb = freqz(hyb_coef,1,w);
figure
plot(f,abs(echo),'-',f,abs(dig_hyb),'-.',f,abs(echo+dig_hyb),':')
axis([0 4000 0 0.4])
legend('echo','digital hybrid response','cancelled signal')
8
Rev. 0.6
AN84
xlabel('frequency')
ylabel('echo')
figure
plot(f,angle(echo),'-',f,angle(dig_hyb),'-.')
axis([0 4000 -pi pi])
legend('echo','digital hybrid response')
xlabel('frequency')
ylabel('echo')
figure
plot(f,20*log10(abs(echo)),'-',f,20*log10(abs(echo+dig_hyb)),'-.')
axis([0 4000 -42 0])
legend('echo','cancelled signal')
xlabel('frequency')
ylabel('rejection')
Rev. 0.6
9
AN84
APPENDIX B—HYBRID COEFFICIENT LOOKUP TABLES
Tables 1–14 (for Rev C and prior versions of the Si3019) and Tables 15–28 (for Rev E and later versions of the
Si3019) provide fixed digital hybrid coefficients to best match the line load with specific EIA line models. For this
calculation, the EIA line model was incorporated into the HL(w) model. The first column shows which line type was
used to calculate the hybrid coefficient. The remaining columns display the hybrid coefficients (Registers 45–52).
Table 1. ACIM = 0000 and CO Termination = 900 Ω + 2.16 µF
Line Type
Hybrid Coefficient #
1
248
251
2
2
3
4
254
5
5
6
0
7
254
254
2
8
EIA 0
EIA 1
249
240
240
239
242
244
244
230
242
240
240
3
254
250
253
252
252
250
7
0
255
238
235
240
233
228
8
2
255
254
254
255
254
253
255
255
255
255
EIA 2
7
254
254
255
253
247
2
EIA 3
5
7
2
EIA 4
1
1
0
EIA 5
7
1
0
EIA 6
4
6
1
EIA 7
248
253
252
251
18
5
234
250
250
250
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
254
255
2
255
254
254
5
2
5
2
Table 2. ACIM = 0000 and CO Termination = 600 Ω
Line Type
Hybrid Coefficient #
1
0
2
3
4
0
5
6
0
7
0
0
2
2
1
1
1
1
0
0
0
8
0
EIA 0
EIA 1
0
0
0
255
2
247
243
240
242
244
244
230
250
249
247
255
241
238
241
234
228
8
4
253
253
252
253
251
7
2
0
EIA 2
8
255
255
255
254
247
2
254
254
255
254
253
255
0
EIA 3
5
9
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
2
18
4
234
253
253
253
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
254
255
1
1
4
1
0
255
4
2
0
10
Rev. 0.6
AN84
Table 3. ACIM = 0000 and CO Termination = 1200 Ω + 376 Ω + 112 nF
Line Type
Hybrid Coefficient #
1
240
247
2
2
3
4
255
8
5
6
3
7
254
255
2
8
1
EIA 0
EIA 1
242
232
238
237
241
244
244
230
233
232
232
7
254
249
253
252
251
249
7
254
234
231
239
233
228
8
4
0
EIA 2
6
254
254
254
252
247
2
254
254
255
253
253
255
0
EIA 3
4
5
2
EIA 4
1
255
0
0
EIA 5
7
0
EIA 6
4
6
1
EIA 7
248
249
248
247
18
8
234
249
249
249
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
253
253
254
3
255
255
255
8
4
0
8
4
0
Table 4. . ACIM = 0000 and CO Termination = 150 Ω + 510 Ω + 47 nF
Line Type
Hybrid Coefficient #
1
3
2
3
4
5
5
6
1
7
0
1
2
2
1
1
1
1
1
1
1
8
EIA 0
EIA 1
249
246
244
241
242
244
244
230
248
247
246
252
249
240
238
241
234
228
8
253
252
254
252
252
251
7
255
255
255
254
255
254
253
255
255
255
255
2
7
1
EIA 2
3
5
255
255
255
253
247
2
EIA 3
5
6
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
4
18
7
234
253
253
252
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
246
247
249
0
3
8
0
2
7
1
Rev. 0.6
11
AN84
Table 5. ACIM = 0000 and CO Termination = 220 Ω + 820 Ω + 150 nF
Line Type
Hybrid Coefficient #
1
6
2
3
4
5
5
6
7
2
1
1
0
0
0
1
1
2
2
1
8
EIA 0
EIA 1
246
246
245
242
242
244
244
230
249
247
246
239
241
240
238
241
234
228
8
253
254
252
250
251
250
7
255
255
254
255
254
252
247
2
255
255
255
254
254
253
253
255
254
255
255
3
2
EIA 2
3
1
EIA 3
5
4
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
6
18
2
234
255
254
254
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
237
239
241
253
254
255
5
3
3
2
Table 6. ACIM = 0000 and CO Termination = 600 Ω + 1.5 µF
Line Type
Hybrid Coefficient #
1
255
255
2
2
3
4
254
3
5
6
7
254
254
1
8
EIA 0
EIA 1
254
246
242
240
242
244
244
230
249
247
246
254
253
241
237
241
234
228
8
254
251
252
252
252
251
7
254
0
254
254
253
253
254
254
253
255
254
254
254
EIA 2
7
254
254
255
253
247
2
EIA 3
5
8
1
EIA 4
1
2
0
EIA 5
7
1
1
EIA 6
4
6
1
EIA 7
248
1
18
2
234
251
251
251
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
251
252
253
255
0
254
254
254
0
3
255
3
0
12
Rev. 0.6
AN84
Table 7. ACIM = 0010 and CO Termination = 220 Ω + 120 Ω + 115 nf
Line Type
Hybrid Coefficient #
1
9
2
3
5
4
5
2
6
255
0
7
0
8
0
EIA 0
EIA 1
16
254
255
2
2
10
9
1
255
0
1
EIA 2
255
1
0
3
0
1
0
EIA 3
253
252
253
254
241
15
0
4
254
0
1
0
0
EIA 4
253
4
0
255
255
4
0
0
0
EIA 5
249
242
19
6
254
8
255
246
2
0
255
254
1
EIA 6
1
2
EIA 7
244
6
11
244
3
253
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
255
255
255
0
0
5
12
7
2
0
0
2
10
9
1
0
255
1
Table 8. ACIM = 0011 and CO Termination = 220 Ω + 820 Ω + 115 nF
Line Type
Hybrid Coefficient #
1
0
2
0
3
4
5
0
6
7
0
8
0
EIA 0
EIA 1
0
0
0
255
255
1
0
255
253
252
255
249
242
18
254
252
253
251
252
2
1
255
254
255
254
253
245
0
0
0
EIA 2
0
255
253
254
253
9
255
255
254
254
3
0
EIA 3
254
255
0
255
255
254
253
1
EIA 4
253
4
EIA 5
EIA 6
1
1
EIA 7
245
1
243
2
10
245
1
253
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
252
253
255
255
255
254
254
255
255
255
0
0
1
1
0
255
0
1
0
0
Rev. 0.6
13
AN84
Table 9. ACIM = 0100 and CO Termination = 370 Ω + 620 Ω + 310 nF
Line Type
Hybrid Coefficient #
1
0
2
3
0
4
0
5
6
0
7
0
8
0
EIA 0
EIA 1
0
0
254
255
1
252
248
246
247
248
249
236
255
253
252
2
1
255
253
252
253
252
8
1
255
0
0
EIA 2
253
251
253
246
240
18
255
0
4
0
255
255
255
254
254
1
EIA 3
6
1
0
EIA 4
252
3
2
0
255
255
2
EIA 5
3
255
247
5
EIA 6
0
8
EIA 7
244
1
14
0
241
255
255
255
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
1
1
0
0
254
2
1
1
255
0
Table 10. ACIM = 0100 and CO Termination = 220 Ω + 820 Ω + 120 nF
Line Type
Hybrid Coefficient #
1
0
2
3
4
6
5
6
2
7
1
8
0
EIA 0
EIA 1
248
249
249
246
247
248
249
236
251
249
249
254
253
251
250
253
246
240
18
255
255
254
252
253
252
8
254
255
1
4
1
1
0
EIA 2
2
0
0
0
EIA 3
4
1
0
255
255
254
254
1
EIA 4
252
3
1
0
255
255
2
EIA 5
2
254
247
5
EIA 6
0
8
EIA 7
244
1
14
5
241
0
254
2
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
249
251
253
0
255
0
0
5
255
255
0
1
254
4
1
1
0
14
Rev. 0.6
AN84
Table 11. ACIM = 0101 and CO Termination = 300 Ω + 1000 Ω + 220 nF
Line Type
Hybrid Coefficient #
1
1
2
3
255
2
4
1
5
6
0
7
0
8
0
EIA 0
EIA 1
0
0
254
255
1
255
252
249
250
251
252
239
1
0
255
254
252
254
253
9
1
0
0
EIA 2
0
2
0
255
255
255
255
3
255
255
255
254
254
1
EIA 3
255
1
4
1
EIA 4
252
3
1
0
EIA 5
251
244
21
254
0
2
255
247
5
EIA 6
0
8
EIA 7
244
1
14
255
0
244
1
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
255
0
0
0
0
0
0
0
254
255
2
0
255
1
0
0
Table 12. ACIM = 0101 and CO Termination = 370 Ω + 620 Ω + 310 nF
Line Type
Hybrid Coefficient #
1
0
2
4
3
4
4
0
5
1
6
1
7
0
8
1
EIA 0
EIA 1
254
255
1
0
6
1
0
2
255
0
1
EIA 2
252
249
250
251
252
239
3
1
3
254
253
255
254
9
1
0
EIA 3
255
1
5
1
0
255
0
EIA 4
252
3
2
0
255
255
3
EIA 5
250
244
21
3
3
255
247
5
255
254
1
EIA 6
0
8
EIA 7
244
1
14
0
244
1
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
1
4
1
0
1
0
0
254
0
6
1
0
2
255
1
Rev. 0.6
15
AN84
Table 13. ACIM = 0101 and CO Termination = 270 Ω + 750 Ω + 150 nF
Line Type
Hybrid Coefficient #
1
0
2
3
2
4
4
5
1
6
2
7
1
8
0
EIA 0
EIA 1
254
253
252
249
250
251
252
239
0
254
255
1
2
3
1
2
1
1
EIA 2
0
2
255
253
254
253
9
1
0
0
EIA 3
254
1
4
1
0
0
EIA 4
252
3
1
0
255
255
3
0
EIA 5
250
244
21
255
0
2
255
247
5
255
254
1
EIA 6
0
8
EIA 7
244
1
14
3
244
2
254
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
254
253
3
1
1
1
0
254
2
3
1
2
1
1
Table 14. ACIM = 1010 and CO Termination = 200 Ω + 560 Ω+ 100 nF
Line Type
Hybrid Coefficient #
1
6
2
5
3
4
0
5
2
6
7
2
2
2
1
1
1
4
0
3
2
2
8
EIA 0
EIA 1
249
247
243
242
244
238
231
8
254
253
252
253
252
250
245
252
252
253
253
255
255
255
255
255
254
251
1
4
4
255
253
254
251
252
2
2
EIA 2
4
2
2
EIA 3
6
0
0
EIA 4
2
0
0
EIA 5
8
1
254
8
EIA 6
6
2
EIA 7
249
7
244
6
12
0
245
3
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
244
246
247
255
255
255
6
5
0
2
4
4
255
2
16
Rev. 0.6
AN84
Table 15. ACIM = 0000 and CO Termination = 900 Ω + 2.16 µF
Line Type
Hybrid Coefficient #
1
248
251
2
2
3
4
254
5
5
6
0
7
254
254
2
8
EIA 0
EIA 1
249
240
240
239
242
244
244
230
242
240
240
3
254
250
253
252
252
250
7
0
255
238
235
240
233
228
8
2
255
254
254
255
254
253
255
255
255
255
EIA 2
7
254
254
255
253
247
2
EIA 3
5
7
2
EIA 4
1
1
0
EIA 5
7
1
0
EIA 6
4
6
1
EIA 7
248
253
252
251
18
5
234
250
250
250
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
254
255
2
255
254
254
5
2
5
2
Table 16. ACIM = 0000 and CO Termination = 600 Ω
Line Type
Hybrid Coefficient #
1
0
2
3
4
0
5
6
0
7
0
0
2
2
1
1
1
1
0
0
0
8
0
EIA 0
EIA 1
0
0
0
255
2
247
243
240
242
244
244
230
250
249
247
255
241
238
241
234
228
8
4
253
253
252
253
251
7
2
0
EIA 2
8
255
255
255
254
247
2
254
254
255
254
253
255
0
EIA 3
5
9
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
2
18
4
234
253
253
253
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
254
255
1
1
4
1
0
255
4
2
0
Rev. 0.6
17
AN84
Table 17. ACIM = 0000 and CO Termination = 1200 Ω + 376 Ω + 112 nF
Line Type
Hybrid Coefficient #
1
240
247
2
2
3
4
255
8
5
6
3
7
254
255
2
8
1
EIA 0
EIA 1
242
232
238
237
241
244
244
230
233
232
232
7
254
249
253
252
251
249
7
254
234
231
239
233
228
8
4
0
EIA 2
6
254
254
254
252
247
2
254
254
255
253
253
255
0
EIA 3
4
5
2
EIA 4
1
255
0
0
EIA 5
7
0
EIA 6
4
6
1
EIA 7
248
249
248
247
18
8
234
249
249
249
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
253
253
254
3
255
255
255
8
4
0
8
4
0
Table 18. ACIM = 0000 and CO Termination = 150 Ω + 510 Ω + 47 nF
Line Type
Hybrid Coefficient #
1
3
2
3
4
5
5
6
1
7
0
1
2
2
1
1
1
1
1
1
1
8
EIA 0
EIA 1
249
246
244
241
242
244
244
230
248
247
246
252
249
240
238
241
234
228
8
253
252
254
252
252
251
7
255
255
255
254
255
254
253
255
255
255
255
2
7
1
EIA 2
3
5
255
255
255
253
247
2
EIA 3
5
6
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
4
18
7
234
253
253
252
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
246
247
249
0
3
8
0
2
7
1
18
Rev. 0.6
AN84
Table 19. ACIM = 0000 and CO Termination = 220 Ω + 820 Ω + 150 nF
Line Type
Hybrid Coefficient #
1
6
2
3
4
5
5
6
7
2
1
1
0
0
0
1
1
2
2
1
8
EIA 0
EIA 1
246
246
245
242
242
244
244
230
249
247
246
239
241
240
238
241
234
228
8
253
254
252
250
251
250
7
255
255
254
255
254
252
247
2
255
255
255
254
254
253
253
255
254
255
255
3
2
EIA 2
3
1
EIA 3
5
4
EIA 4
1
2
EIA 5
7
2
EIA 6
4
6
EIA 7
248
6
18
2
234
255
254
254
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
237
239
241
253
254
255
5
3
3
2
Table 20. ACIM = 0000 and CO Termination = 600 Ω + 1.5 µF
Line Type
Hybrid Coefficient #
1
255
255
2
2
3
4
254
3
5
6
7
254
254
1
8
EIA 0
EIA 1
254
246
242
240
242
244
244
230
249
247
246
254
253
241
237
241
234
228
8
254
251
252
252
252
251
7
254
0
254
254
253
253
254
254
253
255
254
254
254
EIA 2
7
254
254
255
253
247
2
EIA 3
5
8
1
EIA 4
1
2
0
EIA 5
7
1
1
EIA 6
4
6
1
EIA 7
248
1
18
2
234
251
251
251
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
251
252
253
255
0
254
254
254
0
3
255
3
0
Rev. 0.6
19
AN84
Table 21. ACIM = 0010 and CO Termination = 220 Ω + 120 Ω + 115 nF
Line Type
Hybrid Coefficient #
1
9
2
3
5
4
5
2
6
255
0
7
0
8
0
EIA 0
EIA 1
16
254
255
2
2
10
9
1
255
0
1
EIA 2
255
1
0
3
0
1
0
EIA 3
253
252
253
254
241
15
0
4
254
0
1
0
0
EIA 4
253
4
0
255
255
4
0
0
0
EIA 5
249
242
19
6
254
8
255
246
2
0
255
254
1
EIA 6
1
2
EIA 7
244
6
11
244
3
253
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
254
255
255
255
0
0
5
12
7
2
0
0
2
10
9
1
0
255
1
Table 22. ACIM = 0011 and CO Termination = 220 Ω + 820 Ω + 115 nF
Line Type
Hybrid Coefficient #
1
0
2
0
3
4
5
0
6
7
0
8
0
EIA 0
EIA 1
0
0
0
255
255
1
0
255
253
252
255
249
242
18
254
252
253
251
252
2
1
255
254
255
254
253
245
0
0
0
EIA 2
0
255
253
254
253
9
255
255
254
254
3
0
EIA 3
254
255
0
255
255
254
253
1
EIA 4
253
4
EIA 5
EIA 6
1
1
EIA 7
245
1
243
2
10
245
1
253
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
252
253
255
255
255
254
254
255
255
255
0
0
1
1
0
255
0
1
0
0
20
Rev. 0.6
AN84
Table 23. ACIM = 0100 and CO Termination = 370 Ω + 620 Ω + 310 nF
Line Type
Hybrid Coefficient #
1
0
2
3
0
4
0
5
6
0
7
0
8
0
EIA 0
EIA 1
0
0
254
255
1
252
248
246
247
248
249
236
255
253
252
2
1
255
253
252
253
252
8
1
255
0
0
EIA 2
253
251
253
246
240
18
255
0
4
0
255
255
255
254
254
1
EIA 3
6
1
0
EIA 4
252
3
2
0
255
255
2
EIA 5
3
255
247
5
EIA 6
0
8
EIA 7
244
1
14
0
241
255
255
255
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
1
1
0
0
254
2
1
1
255
0
Table 24. ACIM = 0100 and CO Termination = 220 Ω + 820 Ω + 120 nF
Line Type
Hybrid Coefficient #
1
0
2
3
4
6
5
6
2
7
1
8
0
EIA 0
EIA 1
248
249
249
246
247
248
249
236
251
249
249
254
253
251
250
253
246
240
18
255
255
254
252
253
252
8
254
255
1
4
1
1
0
EIA 2
2
0
0
0
EIA 3
4
1
0
255
255
254
254
1
EIA 4
252
3
1
0
255
255
2
EIA 5
2
254
247
5
EIA 6
0
8
EIA 7
244
1
14
5
241
0
254
2
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
249
251
253
0
255
0
0
5
255
255
0
1
254
4
1
1
0
Rev. 0.6
21
AN84
Table 25. ACIM = 0101 and CO Termination = 300 Ω + 1000 Ω + 220 nF
Line Type
Hybrid Coefficient #
1
1
2
3
255
2
4
1
5
6
0
7
0
8
0
EIA 0
EIA 1
0
0
254
255
1
255
252
249
250
251
252
239
1
0
255
254
252
254
253
9
1
0
0
EIA 2
0
2
0
255
255
255
255
3
255
255
255
254
254
1
EIA 3
255
1
4
1
EIA 4
252
3
1
0
EIA 5
251
244
21
254
0
2
255
247
5
EIA 6
0
8
EIA 7
244
1
14
255
0
244
1
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
255
0
0
0
0
0
0
0
254
255
2
0
255
1
0
0
Table 26. ACIM = 0101 and CO Termination = 370 Ω + 620 Ω + 310 nF
Line Type
Hybrid Coefficient #
1
0
2
4
3
4
4
0
5
1
6
1
7
0
8
1
EIA 0
EIA 1
254
255
1
0
6
1
0
2
255
0
1
EIA 2
252
249
250
251
252
239
3
1
3
254
253
255
254
9
1
0
EIA 3
255
1
5
1
0
255
0
EIA 4
252
3
2
0
255
255
3
EIA 5
250
244
21
3
3
255
247
5
255
254
1
EIA 6
0
8
EIA 7
244
1
14
0
244
1
254
0
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
1
4
1
0
1
0
0
254
0
6
1
0
2
255
1
22
Rev. 0.6
AN84
Table 27. ACIM = 0101 and CO Termination = 270 Ω + 750 Ω + 150 nF
Line Type
Hybrid Coefficient #
1
0
2
3
2
4
4
5
1
6
2
7
1
8
0
EIA 0
EIA 1
254
253
252
249
250
251
252
239
0
254
255
1
2
3
1
2
1
1
EIA 2
0
2
255
253
254
253
9
1
0
0
EIA 3
254
1
4
1
0
0
EIA 4
252
3
1
0
255
255
3
0
EIA 5
250
244
21
255
0
2
255
247
5
255
254
1
EIA 6
0
8
EIA 7
244
1
14
3
244
2
254
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
0
0
0
254
253
3
1
1
1
0
254
2
3
1
2
1
1
Table 28. ACIM = 1010 and CO Termination = 200 Ω + 560 Ω + 100 nF
Line Type
Hybrid Coefficient #
1
1
2
2
3
4
5
0
6
7
0
8
0
EIA 0
EIA 1
1
0
0
255
255
1
1
0
255
252
254
251
252
1
1
255
255
255
254
253
245
0
0
0
EIA 2
255
253
253
254
255
242
4
252
250
253
246
239
16
0
0
0
EIA 3
254
255
253
8
0
0
EIA 4
253
3
255
255
3
0
EIA 5
254
253
1
EIA 6
1
EIA 7
244
2
9
245
2
254
1
2000 ft. 22 awg
2000 ft. 24 awg
2000 ft 26 awg
253
254
0
255
255
255
254
255
255
0
1
2
1
1
0
255
1
1
0
0
Rev. 0.6
23
AN84
APPENDIX C—EIA LINE MODELS
2 kft
26 AWG
EIA1
EO
EO
EO
NI
4 kft
26 AWG
3 kft
24 AWG
NI
NI
EIA2
EIA3
1.5 kft
26 AWG
7 kft
26 AWG
12 kft
26 AWG
EO
EO
NI
NI
EIA4
EIA5
1.5 kft
26 AWG
9 kft
24 AWG
6 kft
24 AWG
9 kft
22
AWG
6 kft
22
AWG
3 kft
24
AWG
6 kft
24
AWG
6 kft
24
AWG
EO
EO
NI
NI
EIA6
EIA7
88
88
88
88
88
88
3 kft
24
AWG
6 kft
24
AWG
6 kft
24
AWG
6 kft
22
AWG
6 kft
22
3 kft
22
AWG
AWG
88
88
88
Figure 9. EIA Line Models
24
Rev. 0.6
AN84
DOCUMENT CHANGE LIST
Revision 0.3 to Revision 0.4
Added Figure 5 on page 4.
Added " Appendix C—EIA Line Models" on page 24.
Revision 0.4 to Revision 0.5
Updated Figure 5 on page 4.
Added Tables 17–32 (information for Rev E and later
versions of the Si3019).
Revision 0.5 to Revision 0.6
Updated "1.2. Digital Hybrid Calculation Tool" on
page 3.
Updated Figure 5 on page 4.
Updated " Appendix B—Hybrid Coefficient Lookup
Tables" on page 10.
Rev. 0.6
25
AN84
CONTACT INFORMATION
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26
Rev. 0.6
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