CIRRUS CDB61584A

CDB61584A
Product Databook
FEATURES
■ Socketed CS61584A Dual Line Interface
Dual Line
Interface Unit
■ All Required Components for CS61584A
Evaluation
■ Locations to Evaluate Protection Circuitry
■ LED Status Indications for Alarm Conditions
DESCRIPTION
■ Support for Hardware and Host Modes
The evaluation board includes a socketed CS61584A
dual line interface device and all support components
necessary for evaluation. The board is powered by an
external +5 Volt supply.
The board may be configured for 100Ω twisted-pair T1,
75Ω coax E1, or 120Ω twisted-pair E1 operation. Binding posts and bantam jacks are provided for line
interface connections. Several BNC connectors provide
clock and data I/O at the system interface. Reference
timing may be derived from a quartz crystal, crystal oscillator, or an external reference clock. Four LED
indicators monitor device alarm conditions.
ORDERING INFORMATION:
CDB61584A
5V+ 0V
TTIP1
TCLK1
TPOS1
(TDATA1)
CHANNEL 1
TNEG1
TRING1
RCLK1
RTIP1
CHANNEL 1
RPOS1
(RDATA1)
RNEG1
(BPV1)
RRING1
RESET
CIRCUIT
V+
REFCLK
CS61584A
Hardware Control
and Mode Circuit
LED Status
Indicators
XTL
Oscillator
Circuit
Serial Interface
Control Circuit
TTIP2
TCLK2
TPOS2
(TDATA2)
TRING2
TNEG2
CHANNEL 2
RTIP2
RCLK2
RPOS2
(RDATA2)
RNEG2
(BPV2)
DS261DB2
CHANNEL 2
RRING2
Copyright  Cirrus Logic, Inc. 1998
(All Rights Reserved)
MAR ‘98
CDB61584A
Dual Line Interface Unit
POWER SUPPLY
-
TAOS1, TAOS2: transmit all ones;
As shown on the evaluation board schematic in
Figures 1-5, power is supplied to the board from an
external +5 Volt supply connected to the two binding posts labeled V+ and GND. Zener diode Z1
protects the components on the board from reversed supply connections and over-voltage damage. Capacitor C16 provides power supply
decoupling and ferrite bead L1 helps isolate the
CS61584A and buffer supplies. Both sides of the
evaluation board contain extensive areas of ground
plane to insure optimum performance.
-
LLOOP: local loopback of both channels;
-
RLOOP1,2: remote loopback 1,2;
-
PD1, PD2: power down;
-
ATTEN0, ATTEN1: jitter attenuator selection;
-
CLKE: RCLK edge polarity;
-
1XCLK: clock frequency selection;
-
CONx1, CONx2: line configuration settings.
Capacitors C3, C5-C8, C13, C18, and C38 provide
power supply decoupling for the CS61584A. The
BGREF pin is pulled down through resistor R10 to
provide an internal current reference. The buffers
are decoupled using capacitors C9, C15, and C19.
Ferrite beads L2-L4 help reduce the power supply
noise that is coupled from the buffers to the power
supply.
BOARD CONFIGURATION
Slide switch SW6 selects hardware or host mode
operation. Hardware mode is selected when switch
SW6 is in the "HW" position and sets the MODE
pin of the CS61584A to a logic 0. Host mode is selected when switch SW6 is in the "SW" position
and sets the MODE pin of the CS61584A to a
logic 1.
Hardware Mode
In Hardware mode operation, the evaluation board
is configured using DIP switches SW2, SW3, and
SW4. In this mode, the switches establish the digital control inputs for both line interface channels.
Closing a DIP switch towards the label sets the
CS61584A control pin of the same name to a logic
1. The host processor interface J26 should not be
used in the Hardware mode.
The CDB61584A switches and functions are listed
below:
52
All switch inputs are pulled-down using resistor
networks RP2-RP5.
The LOS1 and LOS2 LED indicators illuminate
when the line interface receiver has detected a loss
of signal. Headers J7 and J13 must be jumpered in
the "TNEG" position to provide connectivity to the
BNC input in Hardware mode.
Host Mode
In Host mode operation, the evaluation board supports serial-port operation over interface port J26
using the printer port of a host PC equipped with
the enclosed software. The evaluation board is connected to the host PC using the ribbon cable provided. The SW2 switch position labeled "ATTEN0"
must be open to set the P/S pin of the CS61584A to
a logic 0 and enable serial-port operation.
An external microprocessor may also interface to
the evaluation board for the purposes of system
software development. The CS61584A interrupt
pin is connected to pin 23 of interface port J26 to
facilitate software development. The SW2 switch
position labeled "CLKE/IPOL" establishes the polarity of the interrupt pin. If an active low interrupt
is selected (IPOL low), the interrupt pin must be
pulled-up through resistor R55 by placing a jumper
on header J24. The SW2 switch position labeled
"RLOOP1" must be in the open position for proper
operation of the interrupt.
The LOS1 and LOS2 LED indicators illuminate
when the line interface receiver has detected a loss
of signal. If coder mode is enabled in the
CS61584A register set, the AIS alarm condition is
DS261DB2
CDB61584A
Dual Line Interface Unit
provided when headers J7 and J13 are jumpered in
the "AIS" position. The AIS1 and AIS2 LED indicators illuminate when the line interface receiver
has detected the all-ones receive input signal. Resistors R26 and R27 pull-down the TNEG(1,2) inputs when coder mode is disabled but headers J7
and J13 are jumpered in the "AIS" position.
Further details concerning Host mode operation are
described in the "readme.txt" file on the enclosed
disk.
Manual Reset
A momentary contact switch SW1 provides a manual reset by forcing the RESET pin of the
CS61584A to a logic 1. Although the transmit and
receive circuitry are continuously calibrated, the
reset can be used to initialize the control logic and
clear the register set. Both channels are powered up
after exiting reset.
TRANSMIT CIRCUIT
The transmit clock and data signals are supplied on
BNC inputs labeled TCLK(1,2), TPOS(1,2), and
TNEG(1,2). In Hardware and Host mode (with
coder mode disabled), data is supplied on the
TPOS(1,2) and TNEG(1,2) BNC inputs in RZ format. In Host mode with coder mode enabled, data
is supplied on the TDATA(1,2) BNC input in NRZ
format and the TNEG(1,2) BNC input may be used
to indicate the AIS alarm condition as described in
the Host Mode section.
The transmitter output is transformer coupled to the
line interface through 1:1.15 step-up transformers
T1 and T4. The signal is available at either the
TTIP(1,2) and TRING(1,2) binding posts or the
TX(1,2) bantam jacks.
Capacitors C2 and C11 prevent output stage imbalances from producing a DC current that may saturate the transformer and result in an output level
offset. Capacitors C1 and C12 provide transmitter
return loss and are socketed so the value may be
changed according to the application. A 220 pF caDS261DB2
pacitor is required for 100Ω twisted-pair T1 or
120Ω twisted-pair E1 applications. A 470 pF capacitor is required for 75Ω coax E1 applications.
These capacitors are included with the evaluation
board.
Optional diode locations D6-D9 and D10-D13 and
optional resistor locations R8-R9 and R18-R19
provide test locations to evaluate transmit line interface protection circuitry.
RECEIVE CIRCUIT
The receive signal is input at either the RTIP(1,2)
and RRING(1,2) binding posts or the RX(1,2) bantam jacks. The receive signal is transformer coupled to the CS61584A through 1:1.15 step-down
transformers T2 and T3.
The receive line is terminated by resistors R3-R4
and R14-R15 to provide impedance matching and
receiver return loss. They are socketed so the values may be changed according to the application.
The evaluation board is supplied from the factory
with 38.3Ω resistors for terminating 100Ω twistedpair T1 lines, 45.3Ω resistors for terminating 120Ω
twisted-pair E1 lines, and 28.7Ω resistors for terminating 75Ω coaxial E1 lines. Capacitors C4 and
C10 provide a differential input voltage reference.
Optional resistor locations R1-R2, R12-R13, R16R17, and R24-R25 provide test locations to evaluate receive line interface protection circuitry.
The recovered clock and data signals are available
on BNC outputs labeled RCLK(1,2), RPOS(1,2),
and RNEG(1,2). In Hardware and Host mode (with
coder mode disabled), data is available on the
RPOS(1,2) and RNEG(1,2) BNC outputs in RZ
format. In Host mode with coder mode enabled,
data is available on the RDATA(1,2) BNC output
in NRZ format and bipolar violations are reported
on BPV(1,2).
53
CDB61584A
Dual Line Interface Unit
REFERENCE CLOCK
JTAG ACCESS
The CDB61584A requires a T1 or E1 reference
clock for operation. This clock may operate at either a 1-X rate (1.544 MHz or 2.048 MHz) or an 8X rate (12.352 MHz or 16.384 MHz) and can be
supplied by either a quartz crystal, crystal oscillator, or external reference. The evaluation board is
supplied from the factory with two crystal oscillators for T1 and E1 operation.
The CS61584A implements JTAG boundary scan
to support board-level testing. Interface port J56
provides access to the four JTAG pins on the
CS61584A. The J-TMS pin of the CS61584A is
pulled-down by resistor R28 to disable boundary
scan unless the pin is externally pulled high using
the interface port.
Quartz Crystal
The evaluation board is supplied from the factory
with Pulse Engineering PE-65388 transformers installed at locations T1-T4. They are socketed to
permit the evaluation of other transformers.
A quartz crystal may be inserted at socket Y1. Because the crystal operates at an 8-X rate, the SW2
switch position labeled "1XCLK" must be open to
set the 1XCLK pin of the CS61584A to a logic 0
and enable 8-X clock operation.
Crystal Oscillator
A crystal oscillator may be inserted at socket U4 in
the orientation indicated by the silkscreen. Header
J14 must be jumpered in the "OSC" position to provide connectivity to the REFCLK pin of the
CS61584A. The SW2 switch position labeled
"1XCLK" must be open (logic 0) for 8-X clock operation or closed (logic 1) for 1-X clock operation.
External Reference
An external reference may be provided at the REFCLK BNC input. Header J14 must be jumpered in
the "REFCLK" position to provide connectivity to
the REFCLK pin of the CS61584A. The SW2
switch position labeled "1XCLK" must be open
(logic 0) for 8-X clock operation or closed (logic 1)
for 1-X clock operation.
BUFFERING
Buffers U2, U3, and U6 provide additional drive
capability for the BNC and Host mode connections.
The buffer outputs are filtered with an RC network
to reduce the transients caused by buffer switching.
54
TRANSFORMER SELECTION
LINE PROTECTION EVALUATION
Several optional resistor and diode locations on the
transmit and receive line interface allow for the installation and evaluation of various types of protection circuitry. Each location is drilled with 60 mil
vias to permit the installation of sockets. These
sockets can be obtained from McKenzie at (510)
651-2700 by requesting part #PPC-SIP-1X32620C and are identical to the socket type installed
at the receive resistor locations on the board. They
allow the line protection circuitry to be easily
changed during testing. Note that the traces forming shorts between the socket locations on the line
interface may need to be cut prior to the installation
of protection circuitry.
PROTOTYPING AREA
Four prototyping areas with power supply and
ground connections are provided on the evaluation
board. These areas can be used to develop and test
a variety of additional circuits such as framer devices, system synchronizer PLLs, or specialized interface logic.
DS261DB2
CDB61584A
Dual Line Interface Unit
EVALUATION HINTS
1) The orientation of pin 1 for the CS61584A is labeled "1" on the left side of the socket U7.
2) A jumper must not be placed on header J10
when using the CDB61584A.
3) Component locations R3-R4, R14-R15, C1,
and C12 must have the correct values installed
according to the application. All the necessary
components are included with the evaluation
board.
4) Closing a DIP switch on SW2, SW3, and SW4
towards the label sets the CS61584A control
pin of the same name to logic 1.
5) When performing a manual loopback of the recovered signal to the transmit signal at the BNC
connectors, the recovered data must be valid on
DS261DB2
the falling edge of RCLK to properly latch the
data in the transmit direction. To accomplish
this, the SW2 switch position labeled "CLKE"
must be closed (logic 1) during Hardware mode
operation or the CLKE bit in the Control A register must be set to a 1 during Host mode operation.
6) Jumpers can be placed on headers J9 and J12 to
provide a ground reference on TRING for 75Ω
coax E1 applications.
7) Properly terminate TTIP/TRING when evaluating the transmit output pulse shape. For more
information concerning pulse shape evaluation,
refer to the Crystal application note entitled
"Measurement and Evaluation of Pulse Shapes
in T1/E1 Transmission Systems."
55
CDB61584A
Dual Line Interface Unit
3
51.1
17
C26
100pF
J2
R30
U2
5
15
U2
51.1
R31
7
U2
51.1
4
6
8
AIS1
U7
CS61584A
CHANNEL 1
R38
R39
U2
R6
3
1
2
51.1
3
4
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
51.1
51.1
J-TDO
VD+
R26
47K
J-TDI
C3
.1µF
VA+
2
Q2
R7
R5
J7
1
470
LOS1
D2
LED
PD1
ATTEN0
1
470
VD+
TTIP1
J31
T
R
TRING1
J8A 1
R8
4
R9
J32
J9
1
T1
D10
J33
J8B 6
R24
VD+
3
5
6
1.15:1
PE -65388
1
T2
RCLK1
RPOS1
RNEG1
TCLK1
TPOS1
TNEG1
LOS1
J-TDO
DGND2
J-TDI
TTIP1
TV+1
TGND1
TRING1
PD1
ATTEN0
N/C-1
2
D11
C1
TV+1
D12
C2
.47µF
D13
RTIP1
ENA
13
12
C31
100pF
VA+
3
2
Q1
D1
LED
ENA
GND
14
U2
C30
100pF
J6
TNEG
10
16
U2
C29
100pF
J5
TPOS
(TDATA1)
.1 µF
VCC
1
U2 19
C28
100pF
J4
TCLK1
20
C27
100pF
J3
RNEG1
(BPV1)
C9
27
RTIP1
28
RRING1
R29
RCLK1
RPOS1
(RDATA1)
VA+
L4
J1
R1
2
T
3
R
RRING1
J34
9
R25
6
1.15:1
PE -65388
R2
5
R4
R3
C4
.47µF
Notes: Components R3, R4, and C1 are socketed to permit value changes
to the application.
Component locations R1, R2, R8, R9, R24, R25, and D10-D13 provide
areas for evaluating protection circuitry.
Figure 1. Channel 1 Circuitry
56
DS261DB2
CDB61584A
Dual Line Interface Unit
J16
VA+
11
L2
U3
VCC
1
20
ENA 19 U3
10
GND
RCLK2
C32
100pF
13
51.1
J17
R42
7
U3
ENA
R41
9
C33
100pF
51.1
5
U3
C34
100pF
R43
C15
J18
.1µF
15
RPOS2
(RDATA2)
RNEG2
(BPV2)
51.1
J19
U7
CS61584A
CHANNEL 2
6
16
4
18
2
U3
C35
100pF
N/C-3 60
TCLK2
J20
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
U3
C36
100pF
51.1
51.1
R50
R51
4
3
10K
CON32
J-TCK
J-TMS VD+
R28
C13
51.1
J13
R27
47K
VA+
D6
2
T4
VD+
1
3
D7
.47µF
R20
R21
470
VD+
C11
1
AIS2
D3
LED
R18
6 J11B
R19
5
1:1.15
PE-65388
LOS2
Q4
1
D8
TNEG2
3
2
PD2
CLKE
C12
J21
470
.1µF
TV+1
TPOS2
(TDATA2)
U3
C37
100pF
VA+
3
2
Q3
2 R22
1
41
RRING2
42
RTIP2
43
N/C-2
RCLK2
RPOS2
RNEG2
TCLK2
TPOS2
TNEG2
LOS2
CON32
J-TCK
J-TMS
TTIP2
TV+2
TGND2
TRING2
PD2
CLKE
C38
22µF
14
9
6
D4
LED
J27
TTIP2
T
R
J28
TRING2
J12
D9
R12
2
T3
1
R16
1 J11A
J29
RTIP2
T
3
R13
6
R14
R15
5
R17
1:1.15
PE-65388
4
R
J30
RRING2
C10
.47µF
Notes: Components R14, R15, and C12 are socketed to permit value changes according
to the application.
Component locations R12, R13, R16-R19, and D6-D9 provide areas for evaluating
protection circuitry.
Figure 2. Channel 2 Circuitry
DS261DB2
57
CDB61584A
Dual Line Interface Unit
VD+
J24
J26
VD+
R56
51.1
26
24
22
20
18
16
14
12
10
8
6
4
2
CS
SD1
SCLK
R55
3.92k
SD0 25
INT 23
21
19
17
15
13
11
9
7
5
3
1
100 pF
R40
51.1
7
24
23
22
21
20
19
18
17
16
15
14
13
J-TD0
J-TD1
J-TMS
T-TCK
C25
U6
9
GND
11
RP2
1
3
5
7
J56
2
4
6
8
1
47k
SW2
1
2
3
4
5
6
7
8
9
10
11
12
C39
U6
13 GND
100 pF
6 5 43 2
TAOS2
TAOS1
LLOOP
RLOOP2
RLOOP1
PD1
PD2
ATTEN0
ATTEN1
CLKE/IPOL
1XCLK
CON01
CON11
CON21
CON31
SW4
CON02 1
8
CON12 2
7
CON22 3
6
CON32 4
5
PD1
PD2
ATTEN0
CLKE/IPOL
1XCLK
8 7 6 5 4 32
VD+
SW3
1
8
2
7
3
6
4
5
CON32
8 7 6 5 4 32
1
RP4
47k
1
6 5 43 2
RP5
47k
GND
1 47k
GND
RP3
6
U6
2
VD+
4
U6
.01µF
5
4
3 51.1 R59
2
1
68
67
66
65
64
63
62
61
C18
N/C-4
ATTEN1
RLOOP1
RLOOP2
LLOOP
TAOS1
TAOS2
CON01
DGND1
DV+
DGND3
CON02
CON11
CON12
CON21
CON22
CON31
9
8
7
6
U6 C24
100pF
100
100pF 14 18
16
pF
C23
C20
51.1
R57
R58
51.1
U7
CS61584A
CONTROL CIRCUITRY
Figure 3. Control Circuitry
58
DS261DB2
CDB61584A
Dual Line Interface Unit
29
RV+1
30
RGND1
31
MODE
32
R10
BGREF
4.99k 33
AGND
34
AV+
35
RESET
36
REFCLK
37
XTALOUT
1XCLK 38 1XCLK
39
RGND2
40
RV+2
U7
CS61584A
TIMING CIRCUITRY
C5
.1µF
C8
Y1
VD+
.1µF
C6
.1µF
C7
1.0µF
VD+
J 10
(must not
be jumped)
VD+
1
SW6
R11
SW1
10K
2
R23
47K
VD+
VD+
2 4
VA+
J14
U4
C14
.1µF
VCC
1 3
REFCLK
8
GND
J15
Figure 4. Timing Circuitry
DS261DB2
59
CDB61584A
Dual Line Interface Unit
GND
V+
J23
J22
VA+
C16 47µF
Z1
VD+
L1
VD+
Prototyping Area
Figure 5. Common Circuitry
60
DS261DB2
• Notes •
Preliminary product information describes products which are in production, but for which full characterization data is not yet available. Cirrus
Logic, Inc. has made best efforts to ensure that the information contained in this document is accurate and reliable. However, the information
is subject to change without notice and is provided “AS IS” without warranty of any kind (express or implied). No responsibility is assumed by
Cirrus Logic, Inc. for the use of this information, nor for infringements of patents or other rights of third parties. This document is the property of
Cirrus Logic, Inc. and implies no license under patents, copyrights, trademarks, or trade secrets. No part of this publication may be copied,
reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photographic, or otherwise). Furthermore, no part of this publication may be used as a basis for manufacture or sale of any items without the prior written consent of Cirrus Logic,
Inc. The names of products of Cirrus Logic, Inc. or other vendors and suppliers appearing in this document may be trademarks or service marks
of their respective owners which may be registered in some jurisdictions. A list of Cirrus Logic, Inc. trademarks and service marks can be found
at http://www.cirrus.com.