STMICROELECTRONICS STU2071B1

STU2071
4B3T U INTERFACE CIRCUIT
PRELIMINARY DATA
4B3T TWO-WIRE U INTERFACE CIRCUIT
FOR LT AND NT APPLICATION
120 kbaud LINE SYMBOL RATE (120 SYMBOLS PER FRAME)
SCRAMBLER AND DESCRAMBLER ACCORDING TO CCITT REC V.29
BARKER CODE (11 SYMBOLS) SYNCHRONIZATION WORD
UNSCRAMBLED 1 KBIT/S HOUSEKEEPING
CHANNEL
ADAPTIVE ECHO CANCELLATION WITH
TRANSVERSAL FILTERING
ADAPTIVE DECISION FEEDBACK EQUALIZATION
AUTOMATIC GAIN CONTROL
PDM AD CONVERTER
AUTOMATIC ACTIVATION AND DEACTIVATION WITH POLARITY ADAPTION
AUTOMATIC CODE VIOLATION DETECTION
POWER FEED UNIT CONTROL
ADVANCED CL3 1.5µm CMOS PROCESS
28 PIN DUAL-IN-LINE PLASTIC PACKAGE
V* DIGITAL INTERFACE
DIP28
ORDERING NUMBER: STU2071B1
PLCC28
ORDERING NUMBER: STU2071FN
SYSTEM OVERVIEW
STU2071 (UIC) provides two transparent 64 kbit/s
B channels, a transparent 16 kbit/s D channel, a
transparent 1 kbit/s service channel and a 1 kbit/s
maintenance channel for loop and error messages on subscriber lines.
UIC enables full duplex continuous data transmission via the standard twisted pair telephone cable. Adaptive Echo cancellation is used to restore
the received data. An equalizer, done with an
adaptive filter, restores the data which are distorted by the transmission line.
The coefficient of the equalizer and echo canceller are conserved during a power down. An all
digital PLL performs both bit and frame synchronization.
The analog front end consists of receive path RX
and transmit path TX, providing a full duplex analog interfacing to the twisted pair telephone cable.
Before data are converted to analog signals, they
September 1994
pass through a digital filter (TX-filter) to reduce
the high frequency components. After D/A conversion the signal is amplified and sent to the hybrid.
The received signal is converted back to digital
data and passed through the RX matching filter to
restore the line signal. The A/D convertor is a
second order sigma/delta modulator which operates with a clock of 15.36 MHz. After timing recovery, achieved by a digital PLL, the received
signal is equalized, in an adaptive digital filter, to
correct for the frequency and group delay distortion of the line.
Power supply status can be read via PFOFF. The
UIC can disable its power supply (DISS), and two
relay drivers outputs are provided (accessible via
B2*) to control the power feed unit (RD1,RD2).
1/18
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
STU2071
Figure 1: UIC Schematic Block Diagram
2/18
LT
PFOFF
DVSS
CLS
XTAL2
XTAL1
4
3
2
1
28
27
26
DISS/COEF
5
25
LIN2
RESETN
6
24
LIN1
DIN
7
23
LOUT2
22
AGND
TSP
8
BURST
PLCC28
19
AVSS
12
13
14
15
16
17
18
S0
11
DVDD
DOUT
S1
LOUT1
S2
AVDD
20
RD2
21
10
RD1
9
FR
CL
DIP28
TEST
PIN CONNECTION (Top view)
D93TL041
STU2071
PIN DESCRIPTION
Pin
Name
1
DVSS(input)
2
PFOFF(input)
3
LT(input)
4
TEST(input)
5
DISS(output)
6
RESETN(input)
Function
Digital Ground.
Power feed off. PFOFF=HIGH is coded by the A-bit indication HI
accessible on DOUT. Active in LT mode only.
LT/NT mode selection.
Test Mode.
A bit channel driven pin. Active in LT mode only.
Hardware Reset.
7
DIN(input)
Digital interface input.
8
TSP(input)
Transmit single pulse. 1 KHz single pulse alternating positive and
negative polarity is transmitted.
9
10
BURST(input)
FR(in/out)
11
DOUT(output)
12
CL(in/out)
13
RD1(output)
Power feeder relay driver.
Power feeder relay driver.
14
RD2(output)
15, 16, 17
S2,S1,S0
18
DVDD(input)
19
20
AVSS(input)
LOUT1(output)
Burst mode selection. Active in LT mode only.
8KHz Digital interface frame clock; input in LT and output in NT mode.
Digital interface output.
Digital interface bit clock; input in LT and output in NT mode.
Time slot pin strap (. Active in LT mode only.
5V +/-5% positive digital power supply.
Analog Ground.
Output to the line.
21
AVDD(input)
5V +/-5% positive analog power supply.
22
AGND(input)
Analog Ground.
23
24,25
LOUT2(output)
LIN1,LIN2(input)
26, 27
XTAL1,XTAL2(inputs)
28
CLS(output)
Output to the line.
Inputs from the line (UK0).
System clock input;nominal frequency is 15.36MHz.
Clock output synchronous to the line receive clock at 7.68MHz.
In LT burst:
APPLICATION AND MODES
The UIC can be used in LT, LT-burst and in NT
mode.
Hereafter a list of the pin bias to set up the desired mode is given.
In LT mode:
Pins
LT
BURST
S0
S1
S2
Value
1
0
0
0
0
Pins
LT
BURST
S0
S1
S2
Value
1
1
time slot
time slot
time slot
In NT:
Pins
LT
BURST
S0
S1
S2
Value
0
0
0
0
1
Test pins should always be tied to GND
3/18
STU2071
MODE DEPENDENT FUNCTIONS
PIN
LT
input
BURST
input
S2, S1, S0
input
DIN
DOUT
input
output
CLS (MHz)
output
CL (KHz)
input
output
FR (KHz)
input
output
LT burst
1
1
static
2048
kbit/s
7.68
4096
–
8
–
NT
0
0
100
256
kbit/s
7.68
–
512
–
8
MODE
LT
1
0
000
256
kbit/s
7.68
512
–
8
–
LTRP
0
0
001
256
kbit/s
–
512
–
8
–
RECOMMENDED APPLICATIONS
LT mode
Figure 2: LT Schematic Application Diagram
DIN:
DOUT:
CL:
FR:
XTAL2:
CLS:
4/18
Data input, datarate = 256 kbit/s, continuous
Data output, datarate = 256 kbit/s, continuous
Data clock input, f = 512 KHz
Frame clock input, f = 8 KHz (1:1)
System clock input, f = 15.36 MHz (Tx clock synchronous to system clock)
Clock output, 7.68 MHz
NTRP
0
0
010
256
kbit/s
7.68
–
512
–
8
STU2071
NT mode
Figure 3: LT Schematic Application Diagram
DIN:
DOUT:
CL:
FR:
XTAL1/2:
CLS:
Data input, datarate = 256 kbit/s, continuous
Data output, datarate = 256 kbit/s, continuous
Data clock input, f = 512 KHz
Frame clock input, f = 8 KHz (1:1)
15.36 MHz Xtal connection (Clock not synchronous to system clock)
Clock output, 7.68 MHz (used to synch S interface)
5/18
STU2071
LT burst mode
Figure 4: LT Burst Mode Schematic Application Diagram.
DIN:
DOUT:
CL:
FR:
XTAL2:
CLS:
6/18
Data input, datarate = 2048 kbit/s, continuous
Data output, datarate = 2048 kbit/s, continuous
Data clock input, f = 4096 KHz
Frame clock input, f = 8 KHz (1:1)
System clock input, f = 15.36 MHz (Tx clock synchronous to system clock)
Clock output, 7.68 MHz
STU2071
Figure 5: Repeater Block Diagram.
To line - NT side
A-wire
To line - LT side
A-wire
UIC
LTrep
DIN
DOUT
DOUT
DIN
HYBRID
UIC
NTrep
CL
CL
FR
FR
HYBRID
XTAL2
XTAL2
B-wire
CLOUT
15.36MHz
CLOUT
512KHz
XTAL1
5V
512KHz
B-wire
0V
15.36MHz
VCO
15.36MHz
PLL circuit
PHASE
COMPARATOR
AND LOOP
FILTER(*)
DC/DC
50mH
2.2µF
2.2µF
50mH
D94TL099
(*)1st order loop filter is sufficient (3dB frequency at 100Hz approx.)
7/18
STU2071
DIGITAL INTERFACE
UIC is provided with a digital serial interface,
named V*, which operates in two modes.
In Fig. 6 the frame format for both modes is
shown.
The base frame consists of:
B1 : 64 kbit/s transparent data channel
B2 : 64 kbit/s transparent data channel
B2* : Monitor channel
B1* : 8 bits so set
D1/D2 : 16 kbit/s D channel
A1..A4 : Command/Indicate channel
T
: Transparent service channel
E
: Extension bit
In Fig. 7 and 8 the timings in Continuous and in
Figure 6: V* Frame Format.
Figure 7: Continuous Mode.
8/18
Burst mode are given.
B2* available messages (do not use in REPETER
modes):
Code
Function
74H
Set RD1 to HIGH
75H
Set RD2 to HIGH
76H
Set RD1 and RD2 to HIGH
77H
Reset RD1 and RD2 to LOW
EFH
Reset frame error counter
(F0-FF)H
NOD
All others
Not defined
In Fig. 7 and 8 the timings in Continuous and in
Burst mode are given.
STU2071
Figure 8: Burst Mode.
uses the frame structure here below. The length
of one frame corresponds to 120 ternary symbols
being transmitted within 1 ms.
LINE FRAME STRUCTURE.
The information flow across the subscriber line
1
T1
2
T1
3
T1
4
T1
5
T1
6
T1
7
T1
8
T1
9
T1
10
T1
11
T1
12
T1
T1
T1
T1
T1
T1
T1
T1
T1
T1
T1
T1
T1
24
T1
T2
T1
T2
T1
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
36
48
T2
T2
T2
T2
T2
T2
T3
T3
T3
T3
T3
T3
60
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T3
T4
T3
T4
T3
T4
72
84
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
96
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
T4
108
T4
SW1
120
1
T5
2
T5
3
T5
4
T5
5
T5
6
T5
7
T5
8
T5
9
T5
19
T5
11
T5
12
T5
T5
M2
T5
T5
T5
T5
T5
T5
T5
T6
T5
T6
T5
T6
T5
T6
T5
T6
T5
T6
T5
T6
T5
T6
24
36
T6
T6
T6
T6
T6
T6
T6
T6
T6
T6
T6
T6
48
T6
T6
T6
T6
T6
T6
T6
SW2
T7
T7
T7
T7
T7
T7
60
72
T7
T7
T7
T7
T7
T7
T7
T7
T7
T7
T7
T7
84
T7
T8
T7
T8
T7
T8
T7
T8
T7
T8
T7
T8
T7
T8
T7
T8
T7
T8
T8
T8
T8
T8
T8
T8
96
108
T8
T8
T8
T8
T8
T8
T8
T8
T8
T8
T8
T8
120
Agenda:
T1. . . . . .T8
M1, M2
SW1, SW2
LT ⇒ NT
NT ⇒ LT
B + B + D - Data (ternary)
Service Data (ternary)
Synchronizing Word
9/18
STU2071
Maintenance and service channel.
The ternary symbols M1 and M2 represent nonscrambled data that can be transmitted at a rate
of 1 kBaud. Those symbols are used for various
purposes:
- Maintenance Channel (control test loops
(LT → NT) and frame errors (LT → NT)
- Service channel (transparent user data and
transmit messages from NT to LT)
Encoding.
The encoding of a binary bit stream is made such
that 4 binary bits correspond to 3 symbols of ternary symbol stream. The encoding follows the
rules of modified monitoring state 43 (MMS43).
COMMAND / INDICATE CHANNEL (A bits)
Command/Indicate codes are define depending on the mode selected (LT or NT).
NT mode COMMANDS (DIN)
ACT
1000
Activate.
Layer 1 is activated at the UK0 interface starting with a ’wake-up’ signal INFO
U1W, followed by INFO U1A during synchronization and closed by INFO U1
when synch is gained.
AW
0000
DC
1111
Awake.
Set the module interface from the power-down to the power-up state. No signal
is emitted at UK0 interface. Even DIN pin pulled LOW can have the same effect.
Deactivation confirmation.
The module interface is deactivated. The transmitter is disabled but the receiver
is still enabled to recognize an awake signal. THe UIC is set in power down
state.
RES
1101
Reset.
Reset the UIC to the initial state.
SY
1100
Synchronize.
Drive the UIC in connect through from module interface to line interface.
Remark: Executing the command RES (1101) is functionally equivalent to pulling the RESETN pin (6)
LOW, with one exception:
a) RES command set pin DISS to HIGH (+5V)
b) pulling RESETN LOW set pin DISS to LOW (0V).
NT mode INDICATION (DOUT)
10/18
ACT
1000
Activate.
The synchronous state of the receiver is reached.
Deactivation confirmation.
The transmitter is disabled but the receiver remains enabled to detect awake
signals at UK0 UIC is set in power down state.
DC
1111
DEAC
0000
Deactivate.
A request to deactivate INFO U0 has been detected.
CT
1100
Connection Through.
The UIC is fully activated.
CTL2
1110
L2
1010
Connection through with loop 2.
A loop 2 command has been detected at UK0.
Loop 2.
Synchronization has been reached during a Loop 2 activation procedure.
RSYN
0100
Resynchronization.
The receiver has lost framing and is attempting to resynchronize.
STU2071
LT mode COMMANDS (DIN)
ACT
1000
Activate.
UIC is set in power-up state, executing the complete activation of Layer 1. The
transparent channel transmission is enabled.
AL
1001
Analog Loop.
The analog transmitter output is looped back to the receiver input which is
disconnected from UK0 interface. A pseudo wake-up procedure is executed.
L2
1010
Loop 2.
Command to close Loop 2 in NT.
LTD
0011
Line Transmission Disabled.
UIC stops transmitting signals on the line and is powered down.
DEAC
0000
Deactivate.
Request to deactivate UK0.
RES
1101
Reset.
Reset the UIC to the initial state.
SSP
0101
Send Single Pulse.
The UIC transmits single pulse at 1 ms time intervals with alternate polarity.
L4
1011
Repeter loop
LT mode INDICATION (DOUT)
ACT
1000
Activation running.
UIC is powered-up and the activation procedure is running.
RDS
0111
Running Digital Sum.
Given during activation procedure. The receiver has reached synchronization.
CT
1100
Connection Through.
Layer 1 activation procedure has been completed. B and D channels are
transparently connected.
DEAC
0001
Deactivation running.
UIC is deactivating in response of a DEAC, RES or LTD command.
DC
1111
Deactivation confirmation.
UIC has completed the deactivation procedure.
RSYN
0100
Resynchronization.
The receiver has lost framing and is attempting to resynchronize.
HI
0011
High Impedance.
When pin PFOFF is HIGH indication HI is output and UIC starts transmitting
INFO U0. Normally used to indicate that remote feeding has been switched off.
POWER DOWN STATE
Power consumption of most functions is reduced;
module interface is not active; C/I messages cannot be exchanged.
OSCILLATOR
Oscillators of 15.36 MHz are required. When in
NT a tollerances of +/-30 ppm is allowed, it is advisable to use in LT a tollerances of +/-20 ppm.
ACTIVATION DEACTIVATION
The ACTIVATION procedure consists of three
steps: AWAKE, SYNCHRONIZE and CONNECT
THROUGH.
Activation times are (max):
COLDSTART 1 sec
WARMSTART 170 msec
LINE RANGE
The LINE RANGE depends on the cable section.
Typically:
up to 4.2Km with 0.4mm cable
- 5.5Km - 0.5mm - 8.0Km - 0.6mm Assumed noise level for such performances is
10uV/SQRT(Hz) on a 200KHz bandwidth.
The DEACTIVATION procedure consists of two
steps: line DEACTIVATION and POWER DOWN.
Deactivation time is (typ) 4 ms.
LT CLOCK JITTER
The phase jitter between Master Clock
(15.36MHz) and interface clock (4.096MHz)
should not exceed 50ns.
11/18
STU2071
ELECTRICAL CHARACTERISTICS
Supply Voltages:
DVDD = 5V +/- 5%
AVDD = 5V +/- 5%
AGND = 2.5V +/- 5% (max curr 0.25mA)
Power consumption
Active = max 280mW (line loaded at 150Ohm)
Power down = Typ. 30mW
= Max. 50mW
DIGITAL INTERFACE STATIC CHARACTERISTICS
Symbol
Parameter
VIH
High Level Input Voltage
VIL
Low Level Input Voltage
Test Condition
Min.
Typ.
Max.
3.5
Unit
V
1.0
V
VOH1
High Level Output Voltage all
outputs except DOUT
IOH1 = 0.4mA
VOH2
High Level Output Voltage
DOUT, (Open Drain)
R to DVDD
R = 1KΩ
VOL1
Low Level Output Voltage all
outputs except DOUT
IOL1 = 0.4mA
0.33
V
VOL2
Low Level Output Voltage
DOUT, (Open Drain)
IOL1 = 0.7mA
0.4
V
CIN
Inputs Capacitance, all inputs
at DOUT if output is off
10
10
pF
pF
COUT
Load Capacitance at all outputs
except at DOUT
25
pF
COUT
IIN
Load Capacitance at DOUT
Input Leakage Current
150
1
pF
µA
12/18
VDD0.66
V
4
V
STU2071
DIGITAL INTERFACE DYNAMIC CHARACTERISTICS
Burst mode.
Conditions
Parameter
Port
from
to
Rise Time tr
Fall Time tf
Setup Time ts
Setup Time ts
Setup Time ts
Setup Time ts
FR, CL
FR, CL
FR
FR
DIN
MPF
1.0V
3.5V
FR, i –
FR, i +
DIN +/–
MPF +/–
3.5V
1.0V
CL, i +
CL, i +
CL, i +
CL, i +
Hold Time th
Hold Time th
Hold Time th
Hold Time th
FR
FR
DIN
MPF
CL, i +
CL, i +
CL, i +
CL, i +
FR, i –
FR, i +
DIN +/–
MPF +/–
Delay Time td
Delay Time td
DOUT
DOUT
CL, i –
CL, i –
DOUT +/–
DOUT +/–
Clock Width tc
Clock Width tc
CL, i
CL, i
CL +/–
CL +/–
CL +/–
CL –/+
C
R to DVDD
Min.
Max.
pF
KΩ
ns
ns
10
10
30
30
30
30
50
50
50
50
60
60
50
150
1
1
0
0
150
200
239
100
249
144
+ = rising edge
– = falling edge
13/18
STU2071
DIGITAL INTERFACE DYNAMIC CHARACTERISTICS (continued)
Continuous mode.
Conditions
Parameter
Rise Time tr
Fall Time tf
Rise Time tr
Fall Time tf
Port
from
to
FR, CL, i
FR, CL, i
FR, CL, o
FR, CL, o
1.0V
3.5V
10%
90%
3.5V
1.0V
90%
10%
Setup Time ts
Setup Time ts
Delay Time td
Hold Time th
Hold Time th
Delay Time td
DIN
MPF
FR
DIN
MPF
DOUT
DIN +/–
MPF +/–
CL, i +
CL, i –
CL, i –
CL, i +
CL, i +
CL, i +
FR, i +
DIN +/–
DIN +/–
DOUT +/–
Setup Time ts
Setup Time th
Delay Time td
Delay Time td
Clock Width tc
Clock Width tp
Pulse Width tp
Pulse Width tp
DIN
DIN
DOUT
FR
DIN +/–1
CL, o –
CL. o +
CL, o +
CL, o +
DIN +/–
DOUT +/–
FR,o +
CL, i
CL, i
CL, i
CL, i
CL +/–
CL +/–
CL +/–
CL +/–
CL +/–
CL +/–
CL –/+
CL –/+
+ = rising edge
– = falling edge
14/18
C
R to DVDD
Min.
Max.
pF
KΩ
ns
ns
10
10
25
25
30
30
30
30
50
50
-200
100
100
25
10
200
500
50
100
25
25
25
25
10
-150
500
150
1830
1830
850
850
2080
2080
1100
1100
STU2071
DIGITAL INTERFACE DYNAMIC CHARACTERISTICS (continued)
Master clock.
Conditions
Parameter
Port
from
to
C
Min.
Max.
pF
ns
ns
Rise Time tr
Fall Time tf
Rise Time tr
Fall Time tf
XTAL2
XTAL2
CLS
CLS
1.0V
3.5V
10%
90%
3.5V
1.0V
90%
10%
10
10
25
25
Pulse Width
CLS
CLS +/–
CLS –/+
25
15
15
15
15
20
+ = rising edge
– = falling edge
Setup Time ts
Hold Time th
Delay min. td
Delay max. td
Delay min. td
(negative)
Delay max. td
DIN, FR, i +/–
CL, i +
CL, i + CL, i –
CL, i + CL, i –
CL, i +
2.5V
2.5V
2.5V
2.5V
2.5V
CL, i +
DIN, FR, i +/–
DOUT +/–
DOUT +/–
FR, i +
2.5V
2.5V
0.4 / 4V
4 / 0.4V
3.5V
CL, i +
2.5V
FR, i +
1V
Setup Time ts
Hold Time ts
Delay max. td
Delay min. td
(negative)
Delay max. td
DIN, +/–
CL, o +
CL, o +
CL, o +
2.5V
2.5V
2.5V
2.5V
CL, o +
DIN +/–
DOUT +/–
FR, o +
2.5V
2.5V
4 / 0.4V
0.33V
CL, o +
2.5V
FR, o +
VDD - 0.66V
Pulse Width tp
Clock Width tc
CL, o +/–
CL, o +/–
2.5V
2.5V
CL, o –/+
CL, o +/–
2.5V
2.5V
Pulse Width tp
Clock Width tc
CLS, MXCL +/–
CLS, MXCL +/–
2.5V
2.5V
CL, o –/+
CL, o +/–
2.5V
2.5V
15/18
STU2071
DIP28 PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
TYP.
MAX.
MIN.
TYP.
a1
0.63
0.025
b
0.45
0.018
b1
0.23
b2
0.31
E
0.009
1.27
D
15.2
MAX.
0.012
0.050
37.34
16.68
1.470
0.598
0.657
e
2.54
0.100
e3
33.02
1.300
F
16/18
inch
14.1
0.555
I
4.445
0.175
L
3.3
0.130
STU2071
PLCC28 PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
TYP.
inch
MAX.
MIN.
TYP.
MAX.
A
12.32
12.57
0.485
0.495
B
11.43
11.58
0.450
0.456
D
4.2
4.57
0.165
0.180
D1
2.29
3.04
0.090
0.120
D2
0.51
E
9.91
0.020
10.92
0.390
0.430
e
1.27
0.050
e3
7.62
0.300
F
0.46
0.018
F1
0.71
0.028
G
0.101
0.004
M
1.24
0.049
M1
1.143
0.045
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STU2071
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics.
© 1994 SGS-THOMSON Microelectronics - All Rights Reserved
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