Appendix B - Functional Operation; Timing; Ground Fault Detect; H2Tu-C-231 List 2 Block Diagram - ADC HiGain H2TU-C-231 User Manual

LTPH-UM-1109-01, Issue 1
A
PPENDIX
ADC HDSL2 technology provides full-duplex services at standard DS1 rates over copper wires between an
H2TU-C and an H2TU-R, which comprise one HiGain HDSL2 system. HiGain HDSL2 systems use Overlapped
Pulse Amplitude Modulation Transmission with Interlocking Spectra (OPTIS) transceiver systems to establish
full-duplex, 1.552 kbps data channels between the H2TU-C-231 and a remotely located H2TU-R.
A block diagram of the H2TU-C-231 is shown in
stream from the DSX-1 digital cross-connect interface. The H2TU-C-231 contains a DS1 frame synchronizer
controlled by an 8-bit microprocessor that determines the type of framing on the DS1 stream and synchronizes to
it. The H2TU-C-231 recognizes SuperFrame (SF) or Extended SuperFrame (ESF) framing. When the data is
unframed, the H2TU-C-231 arbitrarily defines a frame bit.
D
Tip
42
S
IN
X
43
Ring
1
BRG
LINE
A
Fuse alarm
32
-48Vdc 39
Power Supply
B
15
16
Ground
19
44
Management bus
46
Pre-equalizer
LINE
Select
BRG
D
Tip 1
S
49
OUT
X
50
1
Ring 1
20
Alarms
21
T
IMING
The low-loop wander (0.5 UI max) of an H2TU-C-231, when used with remote units, allows the circuit to be used
in all critical timing applications, including those used to transport Stratum 1 timing.
G F
ROUND AULT
The H2TU-C-231 has a Ground Fault Detect (GFD) circuit which detects a ground or a resistive path to ground
on any wire of the HDSL2 loop. This makes the product compliant with the Class A2 requirements of GR-1089.
H2TU-C-231 List 2
B - F
UNCTIONAL
HDSL2
T1
Framer Framer
MODE SEL
Microprocessor
LEDs
Figure 33. H2TU-C-231 List 2 Block Diagram
D
ETECT
January 9, 2002
O
PERATION
Figure 33. The H2TU-C-231 receives a 1.544 Mbps DSX-1 data
A
B
(Ground isolated
and ground fault detect)
RS-232 (front panel)

Appendix B - Functional Operation

HDSL 2
XCVR
-180 Vdc +
Power
Supply
_
Tip
34
HDSL 2
SPAN
35
Ring
59