ACS8520T Semtech, ACS8520T Datasheet - Page 138

• Manufacturer Part Number: ACS8520T
• Description: Synchronous Equipment Timing Source (SETS) for Stratum 3/4E/4 and SMC Systems
• Manufacturer: Semtech

DC Characteristics: AMI Input/Output Port
(Across all operating Conditions, unless otherwise stated.)
The Alternate Mark Inversion (AMI) signal is DC balanced
and consists of positive and negative pulses with a peak-
to-peak voltage of 2.0 ±0.2 V.
The electrical specifications are taken from option a) of
Table 2/G.703 - Digital 64 kbit/s centralized clock
interface, from ITU G.703
The electrical characteristics of the 64 kbit/s interface
are as follows:
Nominal bit rate: 64 kbit/s. The tolerance is determined
by the network clock stability.
Table 40 DC Characteristics: AMI Input/Output Port
Revision 3.02/October 2005 © Semtech Corp.
ADVANCED COMMUNICATIONS
Across all operating conditions, unless otherwise stated
Input Pulse Width
Input Pulse Rise/Fall Time
AMI Input Voltage High
AMI Input Voltage Middle
AMI Input Voltage Low
AMI Output Current Drive
AMI Output High Voltage
Output Current = 20mA
AMI Output Low Voltage
Output Current = 20mA
Nominal Test Load Impedance
“Mark” Amplitude After Transformer
“Space” Amplitude After Transformer
Parameter
[6]
.
Symbol
V
V
V
V
I
V
V
V
AMIOUT
R
VIM AMI
VIL AMI
OH AMI
OL AMI
SPACE
t
IH AMI
MARK
t
TEST
R/F
PW
FINAL
Page 138
V
Minimum
DD
1.56
- 0.1
2.5
1.5
0.9
- 0.16
0
There should be a symmetrical pair carrying the
composite timing signal (64 kHz and 8 kHz). The use of
transformers is recommended.
Over-voltage protection requirement: refer to
Recommendation K.41
Code conversion rules:
The data signals are coded in AMI code with 100% duty
cycle. The composite clock timing signals convey the
64 kHz bit-timing information using AMI coding with a
50% to 70% duty ratio and the 8 kHz octet phase
information by introducing violations in the code rule. The
structure of the signals and voltage level are shown in
Figure 25, Figure 26 and Figure 27.
-
-
-
-
Typical
1.65
110
7.8
1.0
0
-
-
-
-
-
-
[16]
Maximum
V
ACS8520 SETS
DD
14.04
0.16
1.8
1.4
1.1
0.1
20
5
+ 0.3
-
-
DATASHEET
www.semtech.com
Units
mA
µs
µs
Ω
V
V
V
V
V
V
V