™
Le79R79
Ringing Subscriber Line Interface Circuit
VE580 Series
APPLICATIONS
Ideal for short-loop applications
Ideal for ISDN-TA and fixed radio access applications
Integrated Access Devices (IADs)
Network Interface Units (NIUs)
Cable Modems
DSL Modems
Set Top / House Side Boxes
Intelligent PBX
Pain Gain
FXS Cards
Voice over ISDN or T1/E1
Smart Residential Gateways
WLL, APON, FITL, NGN, and all other short-loop CPE/
Enterprise telephony applications
ORDERING INFORMATION
Device1
Le79R79-1DJC
Le79R79-2DJC
Through trapezoidal ringing
On-chip ring-trip detector
Low standby state power
Battery operation:
— VBAT1: –40.5 to –75 V
— VBAT2: –19 V to VBAT1
On-chip battery switching and feed selection
On-hook transmission
Two-wire impedance set by single external impedance
Programmable constant-current feed
Programmable Open Circuit voltage
Programmable loop-detect threshold
Current gain = 1000
Ground-key detector
Polarity reversal option available
Internal VEE regulator (no external –5 V power supply
required)
RELATED LITERATURE
080917 Ve790 Series RSLIC Device Product Brief
080158 Le79R70/79/100/101 Technical Overview
080914 Le79R79 RSLIC Device User’s Guide
080810 Le71HR0021 Reference Design User’s Guide
080255 Le71HE0040J Evaluation Board User’s Guide
080458 Le79R100/101 v. Le79R79 Comparison Brief
080753 Le58QL02/021/031 QLSLAC™ Data Sheet
Packing4
32-pin PLCC
(Green package)
Tube
32-pin QFN
(Green package)
Tray
Le79R79-3DJC
Le79R79-1FQC
Le79R79-2FQC
-1: 52 dB Longitudinal Balance, Polarity Reversal
-2: 63 dB Longitudinal Balance, Polarity Reversal
-3: 52 dB Longitudinal Balance, No Polarity Reversal
1.
Zarlink reserves the right to fulfill all orders for this device with
parts marked with the "Am" part number prefix until all inventory
bearing this mark has been depleted. Note that parts marked with
either the "Am" or the "Le" part number prefix are equivalent
devices in terms of form, fit, and function—the prefix appearing on
the topside mark is the only difference.
2.
Due to size constraints, QFN devices are marked by omitting the
“Le” prefix and the performance grade dash character. For
example, Le79R79-1FQC is marked 79R791FQC.
3.
The green package meets RoHS Directive 2002/95/EC of the
European Council to minimize the environmental impact of
electrical equipment.
4.
For delivery using a tape and reel packing system, add a "T" suffix
to the OPN (Ordering Part Number) when placing an order.
FEATURES
Package Type2, 3
DESCRIPTION
The Le79R79 Ringing SLIC device is a bipolar monolithic SLIC
that offers on-chip ringing. Designers can achieve significant
cost reductions at the system level for short-loop applications
by integrating the ringing function on chip. Examples of such
applications would be ISDN terminal adaptors, fiber-in-theloop, radio-in-the-loop, hybrid fiber/coax and video telephony
(home-side) boxes. The Le79R79 Ringing SLIC device can
provide sufficient voltage to meet the stringent LSSGR fiveringer equivalent specification. Using a CMOS-compatible
input waveform and wave shaping R-C network, the Le79R79
Ringing SLIC device can provide trapezoidal wave ringing to
meet various design requirements.
See the Le79R79 Block Diagram, on page 4.
Document ID#: 080152 Date:
Sep 19, 2007
Rev:
O
Version: 2
Distribution:
Public Document
Le79R79
Data Sheet
TABLE OF CONTENTS
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Related Literature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Ordering Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Connection Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Operating Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Transmission Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Longitudinal Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Idle Channel Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Insertion Loss and Four-to-Four-Wire Balance Return Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Line Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Power Supply Rejection Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Supply Currents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Logic Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Ring-Trip Detector Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Ring Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Ground-Key Detector Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Loop Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Relay Driver Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Relay Driver Schematic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
SLIC Device Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
User-Programmable Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
DC Feed Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Ring-Trip Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Test Circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Le79R79 Test Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Application Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Physical Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
32-pin PLCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
32-pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision B to C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision C to D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision D to E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision E to F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision F to G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision G to H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision H to I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision I to J1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision J1 to K1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision K1 to L1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision L1 to M1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Revision M1 to N1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
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Zarlink Semiconductor Inc.
Le79R79
Data Sheet
Revision N1 to N2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Revision N2 to O1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Revision O1 to O2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
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Zarlink Semiconductor Inc.
Le79R79
Data Sheet
PRODUCT DESCRIPTION
The Zarlink family of subscriber line interface circuit (SLIC) products provide the telephone interface functions required
throughout the worldwide market. Zarlink SLIC devices address all major telephony markets including central office (CO), private
branch exchange (PBX), digital loop carrier (DLC), fiber-in-the-loop (FITL), radio-in-the-loop (RITL), hybrid fiber coax (HFC), and
video telephony applications.
The Zarlink SLIC devices offer support of BORSHT (battery feed, overvoltage protection, ringing, supervision, hybrid, and test)
functions with features including current limiting, on-hook transmission, polarity reversal, Tip Open, and loop-current detection.
These features allow reduction of linecard cost by minimizing component count, conserving board space, and supporting
automated manufacturing.
The Zarlink SLIC devices provide the two- to four-wire hybrid function, DC-loop feed, and two-wire supervision. Two-wire
termination is programmed by a scaled impedance network. Transhybrid balance can be achieved with an external balance circuit
or simply programmed using a companion Zarlink codec/filter, such as the Le58QL0xx Quad SLAC (QLSLAC™) device.
The Le79R79 Ringing SLIC device is a bipolar monolithic SLIC that offers on-chip ringing. Now designers can achieve significant
cost reductions at the system level for short-loop applications by integrating the ringing function on chip. Examples of such
applications would be ISDN terminal adaptors, fiber-in-the-loop, radio-in-the-loop, hybrid fiber/coax and video telephony (homeside) boxes. The Le79R79 Ringing SLIC can provide sufficient voltage to meet the stringent LSSGR five-ringer equivalent
specification. Using a CMOS-compatible input waveform and wave shaping R-C network, the Le79R79 Ringing SLIC can provide
trapezoidal wave ringing to meet various design requirements.
In order to further enhance the suitability of this device in short-loop, distributed switching applications, Zarlink has maximized
power savings by incorporating battery switching on chip. The Le79R79 Ringing SLIC device switches between two battery
supplies such that in the off-hook (active) state, a low battery is used to save power. In order to meet the Open Circuit voltage
requirements of fax machines and maintenance termination units (MTU), the SLIC device automatically switches to a higher
voltage in the On-hook (Standby) state.
Like all of the Zarlink SLIC devices, the Le79R79 Ringing SLIC device supports on-hook transmission, ring-trip detection,
programmable loop-detect threshold, and is available with on-chip polarity reversal. The Le79R79 Ringing SLIC device is a
programmable constant-current feed device with two on-chip relay drivers to operate external relays. Several performance grades
are available to meet both CCITT and LSSGR requirements, including various longitudinal balance options.
Figure 1. Le79R79 Block Diagram
Relay Driver
RYOUT2
Relay Driver
RYOUT1
RTRIP1
RTRIP2
RYE
A(TIP)
D1
D2
C1
Ring-Trip
Detector
Input Decoder
and Control
Ground-Key
Detector
HPA
Two-Wire
Interface
C2
C3
E1
Off-Hook
Detector
DET
Signal
Transmission
RD
VTX
RSN
HPB
B(RING)
RINGIN
RDC
RDCR
Power-Feed
Controller
VBAT2
RSGL
RSGH
B2EN
Switch
Driver
VBAT1
VCC VNEG BGND
AGND/DGND
4
Zarlink Semiconductor Inc.
Le79R79
Data Sheet
RD
1
B(RING)
2
A(TIP)
3
VBAT2
4
BGND
RYOUT2
VCC
CONNECTION DIAGRAMS
32
31
30
RYE
5
29
RTRIP1
RYOUT1
6
28
RTRIP2
27
HPB
8
26
HPA
D1
9
25
RINGIN
E1
10
24
RDCR
C3
11
23
VTX
C2
12
22
VNEG
DET
13
21
RSN
RYE
20
AGND/DGND
RD
NC
RSGH
19
RDC
D2
RSGL
C1
18
AX
17
BX
16
BGND
15
VBAT2
32
1
14
VCC
Top View
32-pin PLCC
31
30
29
28
27
26
RTRIP1
7
RYOUT2
B2EN
VBAT1
25
24
RTRIP2
RYOUT1
2
23
HPB
B2EN
3
22
HPA
VBAT1
4
21
RINGIN
32-pin QFN
D1
5
20
RDCR
E1
6
19
VTX
C3
7
18
VNEG
C2
8
11
12
13
14
15
NC
RSGH
RSGL
RDC
17
16
RSN
AGND
10
D2
DET
9
C1
EXPOSED PAD
Note:
1.
Pin 1 is marked for orientation.
2.
NC = No connect.
3.
The thermally enhanced QFN package features an exposed pad on the underside which must be electrically tied to VBAT1.
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Zarlink Semiconductor Inc.
Le79R79
Data Sheet
PIN DESCRIPTIONS
Pin Names
Type
Description
AGND/DGND
Ground
Analog and digital ground
A(TIP)
Output
Output of A(TIP) power amplifier
B2EN
Input
VBAT2 Enable. Logic Low enables operation from VBAT2. Logic High enables operation from VBAT1. TTL
compatible.
BGND
Ground
Battery (power) ground
B(RING)
Output
Output of B(RING) power amplifier
C3–C1
Input
Decoder. SLIC control pins. C3 is MSB and C1 is LSB. TTL compatible.
D1
Input
Relay1 Control. TTL compatible. Logic Low activates the Relay1 relay driver.
D2
Input
Relay2 Control. (Option) TTL compatible. Logic Low activates the Relay2 relay driver.
DET
Output
Hook switch detector. When enabled, a logic Low indicates that the selected detector is tripped. The logic
inputs C3–C1 and E1 select the detector. The output is open collector with a built-in 15 kΩ pull-up resistor.
E1
Input
Ground-Key Enable. (Option) A logic High selects the off-hook detector. A logic Low selects the groundkey detector. TTL compatible.
HPA
Capacitor
High-Pass Filter. A(TIP) side of high-pass filter capacitor.
HPB
Capacitor
High-Pass Filter. B(RING) side of high-pass filter capacitor.
NC
—
Not internally connected.
RD
Resistor
Detect Resistor. Detector threshold set and filter pin.
RDC
Output
DC Feed Resistor. Connection point for the DC-feed current programming network. The other end of the
network connects to the receiver summing node (RSN). The sign of VRDC is negative for normal polarity
and positive for reverse polarity.
RDCR
—
Connection point for feedback during ringing.
RINGIN
Input
Ring Signal. Pin for ring signal input. Square-wave shaped by external RC filter. Requires 50% duty cycle.
CMOS-compatible input.
RSGH
Input
Saturation Guard High. Pin for resistor to adjust Open Circuit voltage when operating from VBAT1.
RSGL
Input
Saturation Guard Low. Pin for resistor to adjust the anti-saturation cut-in voltage when operating from
both VBAT1 and VBAT2.
RSN
Input
Receive Summing Node. The metallic current (both AC and DC) between A(TIP) and B(RING) is equal
to 1000 x the current into this pin. The networks that program receive gain, two-wire impedance, and feed
resistance all connect to this node.
RTRIP1
Input
Ring-Trip Detector. Ring-trip detector threshold set and filter pin.
RTRIP2
Input
Ring-Trip Detector. Ring-trip detector threshold offset (switch to VBAT1). For power conservation in any
nonringing state, this switch is open.
RYE
Output
Common Emitter of RYOUT1/RYOUT2. Emitter output of RYOUT1 and RYOUT2. Normally connected to
relay ground.
RYOUT1
Output
Relay/Switch Driver. Open collector driver with emitter internally connected to RYE.
RYOUT2
Output
Relay/Switch Driver. (Option) Open collector driver with emitter internally connected to RYE.
VBAT1
Battery
Battery supply and connection to substrate.
VBAT2
Battery
Power supply to output amplifiers. Connect to off-hook battery through a diode.
VCC
Power
Positive analog power supply
VNEG
Power
Negative analog power supply. This pin is the return for the internal VEE regulator.
VTX
Output
Transmit Audio. This output is a 0.5066 gain version of the A(TIP) and B(RING) metallic AC voltage. VTX
also sources the two-wire input impedance programming network.
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Zarlink Semiconductor Inc.
Le79R79
Data Sheet
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings
Stresses greater than those listed under Absolute Maximum Ratings can cause permanent device failure. Functionality at or
above these limits is not implied. Exposure to absolute maximum ratings for extended periods can affect device reliability.
VNEG with respect to AGND/DGND
–55 to +150º C
0.4 to +7 V
0.4 V to VBAT2
VBAT2
VBAT1 to GND
Storage Temperature
VCC with respect to AGND/DGND
VBAT1 with respect to AGND/DGND:
Continuous
10 ms
BGND with respect to AGND/DGND:
A(TIP) or B(RING) to BGND:
Continuous
+0.4 to –80 V
+0.4 to –85 V
+3 to –3 V
VBAT1 –5 to +1 V
10 ms (F = 0.1 Hz)
VBAT1 –10 to +5 V
1 µs (F = 0.1 Hz)
VBAT1 –15 to +8 V
VBAT1 –20 to +12 V
250 ns (F = 0.1 Hz)
Current from A(TIP) or B(RING)
RYOUT1, RYOUT2 current
RYOUT1, RYOUT2 voltage
RYOUT1, RYOUT2 transient
RYE voltage
±150 mA
75 mA
RYE to +7 V
RYE to +10 V
BGND to VBAT1
C3–C1, D2–D1, E1, B2EN, and RINGIN:
Input voltage
Maximum power dissipation, continuous,
TA = 70º C, No heat sink (see note)
In 32-pin PLCC package
In 32-pin QFN package
–0.4 V to VCC + 0.4 V
1.67 W
3.00 W
θJA
45° C/W
Thermal data:
In 32-pin PLCC package
In 32-pin QFN package
25° C/W
JESD22 Class 1C compliant
ESD Immunity (Human Body Model)
Note:
1.
Thermal limiting circuitry on the chip will shut down the circuit at a junction temperature of about 165ºC. Continuous operation above 145ºC
junction temperature may degrade device reliability.
2.
The thermal performance of a thermally enhanced package is assured through optimized printed circuit board layout. Specified performance
requires that the exposed thermal pad be soldered to an equally sized exposed copper surface, which, in turn, conducts heat through
multiple vias to a large internal copper plane.
Package Assembly
Green package devices are assembled with enhanced, environmental compatible lead-free, halogen-free, and antimony-free
materials. The leads possess a matte-tin plating which is compatible with conventional board assembly processes or newer leadfree board assembly processes. The peak soldering temperature should not exceed 245°C during printed circuit board assembly.
Refer to IPC/JEDEC J-Std-020B Table 5-2 for the recommended solder reflow temperature profile.
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Zarlink Semiconductor Inc.
Le79R79
Data Sheet
OPERATING RANGES
Zarlink guarantees the performance of this device over commercial (0 to 70º C) and industrial (-40 to 85ºC) temperature ranges
by conducting electrical characterization over each range and by conducting a production test with single insertion coupled to
periodic sampling. These characterization and test procedures comply with section 4.6.2 of Bellcore GR-357-CORE Component
Reliability Assurance Requirements for Telecommunications Equipment.
Environmental Ranges
0 to 70°C Commercial
Ambient Temperature
–40 to +85 °C extended temperature
Ambient Relative Humidity
15 to 85%
Electrical Ranges
VCC
4.75 to 5.25 V
VNEG
–4.75 V to VBAT2
VBAT1
–40.5 to –75 V
VBAT2
–19 V to VBAT1
AGND/DGND
0V
BGND with respect to AGND/DGND
–100 to +100 mV
Load resistance on VTX to ground
20 kΩ minimum
SPECIFICATIONS
Transmission Performance
Description
2-wire return loss
Test Conditions (See Note 1)
200 Hz to 3.4 kHz (See Figure 6.)
Min
Typ
ZVTX, analog output impedance
3
VVTX, analog output offset voltage
Max
26
20
0 to +70° C
–35
+35
−40 to +85° C
–40
+40
ZRSN, analog input impedance
1
20
Unit
Note
dB
1, 4, 6
Ω
4
mV
Ω
4
Overload level, 2-wire and 4-wire, Off
hook
Active state
2.5
Vpk
2a
Overload level, 2-wire
On hook, RLAC = 600 Ω
0.88
Vrms
2b
THD (Total Harmonic Distortion)
+3 dBm, BAT 2 = −24 V
THD, On hook, OHT state
0dBm, RLAC = 600 Ω
BAT1 = −75 V
dB
5
8
Zarlink Semiconductor Inc.
–64
–50
–40
Le79R79
Data Sheet
Longitudinal Performance
(See Figure 8.)
Description
Longitudinal to metallic
L-T, L-4 balance
Test Conditions (See Note 1)
Min
200 Hz to 3.4 kHz
−1, −3*
52
normal polarity
−2, −4
63
reverse polarity
−2
54
normal polarity,
−40° C to +85 ° C
−2, −4
1 kHz to 3.4 kHz
−1, −3*
52
normal polarity
−2, −4
58
reverse polarity
−2
54
normal polarity,
−40° C to +85° C
Typ
Max
Unit
58
4
dB
54
−2, −4
Longitudinal signal generation 4-L
200 Hz to 800 Hz normal polarity
42
Longitudinal current per pin (A or B)
Active or OHT state
12
Longitudinal impedance at A or B
0 to 100 Hz, TA = +25° C
Note
4
28
mArms
25
Ω/pin
4
Idle Channel Noise
Description
Test Conditions (See Note 1)
Min
0 to +70° C
C-message weighted noise
Typ
+7
−40 to +85° C
+11
+12
0 to +70° C
Phosphometric weighted noise
Max
–83
−40 to +85° C
–79
–78
Unit
Note
dBrnC
dBmp
4
Insertion Loss and Four-to-Four-Wire Balance Return Signal
(See Figure 6 and Figure 7.)
Min
Typ
Max
Gain accuracy, 4-to-2-wire
Description
0 dBm, 1 kHz
Test Conditions (See Note 1)
–0.20
0
+0.20
Gain accuracy, 2-to-4-wire
0 dBm, 1 kHz
–6.22
–6.02
–5.82
Gain accuracy, 4-to-2-wire
OHT state, on hook
–0.35
0
+0.35
Gain accuracy, 2-to-4-wire
OHT state, on hook
–6.37
–6.02
–5.77
Unit
Note
4-to-4-wire
3
4-to-4-wire
Gain accuracy over frequency
300 to 3400 Hz
relative to 1 kHz
Gain tracking
+3 dBm to –55 dBm
relative to 0 dBm
Gain tracking
0 dBm to –37
0 to +70° C
–0.10
+0.10
−40 to +85° C
–0.15
+0.15
0 to +70° C
–0.10
+0.10
−40 to +85° C
–0.15
+0.15
0 to +70° C
–0.10
+0.10
–0.15
+0.15
–0.35
+0.35
−40 to +85° C
OHT state, on hook
+3 dBm to 0 dBm
Group delay
0 dBm, 1kHz
3
9
Zarlink Semiconductor Inc.
dB
3, 4
3
µs
1, 4, 6
Le79R79
Data Sheet
Line Characteristics
Description
IL, Loop-current accuracy
IL, Long Loops, Active state
Min
Typ
Max
IL in constant-current region,
B2EN=0
Test Conditions (See Note 1)
0.87IL
IL
1.085IL
RLDC = 600 Ω, RSGL = open
20
21.7
RLDC = 750 Ω, RSGL = short
20
V BAT1 – 10 V
I L = ------------------------------------R L + 400
IL, Accuracy, Standby state
ILLIM
0.8IL
IL
1.2IL
IL = constant-current region
TA = 25° C
18
27
39
−40 to +85° C
18
27
Active, A and B to ground
55
OHT, A and B to ground
55
mA
4
4
IL, Loop current, Open Circuit state
RL = 0
100
RL = 0
100
IB, Pin B current, Tip Open state
B to ground
VA, Standby, ground start signaling
A to −48 V = 7 kΩ,
B to ground = 100 Ω
34
VAB, Open Circuit voltage
Note
110
IA, Pin A leakage, Tip Open state
−7.5
Unit
µA
mA
−5
V
42.8
4
8
Power Supply Rejection Ratio
(VRIPPLE = 100 mVrms), Active Normal State
Description
Test Conditions (See Note 1)
Min
Typ
Max
VCC
50 to 3400 Hz
33
50
VNEG
50 to 3400 Hz
30
40
VBAT1
50 to 3400 Hz
30
50
VBAT2
50 to 3400 Hz
30
50
Min
Typ
Max
48
100
Unit
Note
dB
5
Unit
Note
Power Dissipation
Description
Test Conditions (See Note 1)
On hook, Open Circuit state
VBAT1
On hook, Standby state
VBAT2
55
80
On hook, OHT state
VBAT1
200
300
On hook, Active state
VBAT1
220
350
Off hook, Standby state
VBAT1 or VBAT2
RL = 300 Ω
2000
2800
Off hook, OHT state
VBAT1
RL = 300 Ω
2000
2200
Off hook, Active state
VBAT2
RL = 300 Ω
550
750
10
Zarlink Semiconductor Inc.
10
mW
10
Le79R79
Data Sheet
Supply Currents
Description
Test Conditions (See Note 1)
ICC,
On-hook VCC supply current
INEG,
On-hook VNEG supply current
IBAT,
On-hook VBAT supply current
Typ
Max
Open Circuit state
Min
3.0
4.5
Standby state
3.2
5.5
OHT state
6.2
8.0
Active state-normal
6.5
9.0
Open Circuit state
0.1
0.2
Standby state
0.1
0.2
OHT state
0.7
1.1
Active state-normal
0.7
1.1
Open Circuit state
0.45
1.0
Standby state
0.6
1.5
OHT state
2.0
4.0
Active state-normal
2.7
5.0
Typ
Max
Unit
Note
mA
Logic Inputs
(Applies to C3–C1, D2–D1, E1, and B2EN).
Description
Test Conditions
VIH, Input High voltage
Min
2.0
VIL, Input Low voltage
0.8
IIH, Input High current
–75
IIL, Input Low current
–400
40
Unit
Note
V
µA
Logic Output
(DET)
Description
Test Conditions (See Note 1)
VOL, Output Low voltage
IOUT = 0.8 mA, 15 kΩ to VCC
VOH, Output High voltage
IOUT = –0.1 mA, 15 kΩ to VCC
Min
Typ
Max
0.40
2.4
Unit
Note
V
Ring-Trip Detector Input
Description
Ring detect accuracy
Test Conditions (See Note 1)
Min
BAT1 – 1- + 24 µA • 335
IRTD = -------------------------- RRT1
Typ
Max
–10
Unit
+10
Note
%
Ring Signal
Min
Typ
VAB, Ringing
Description
BAT1 = −75 V, Ringload = 1570 Ω
Test Conditions (See Note 1)
66
69
VAB, Ringing offset
VRINGIN = 2.5 V
−10
0
10
150
180
210
Min
Typ
Max
Unit
2
5
10
kΩ
∆V AB ⁄ ∆V RINGIN ( RINGIN gain )
Max
Unit
Note
Vpk
7
V
Ground-Key Detector Thresholds
Description
Test Conditions (See Note 1)
Ground-key resistive threshold
B to ground
Ground-key current threshold
B to ground
11
11
Zarlink Semiconductor Inc.
mA
Note
Le79R79
Data Sheet
Loop Detector
Description
Test Conditions (See Note 1)
RLTH, Loop-resistance detect
threshold
Min
Typ
Max
Active, VBAT1
−20
20
Active, VBAT2
−20
20
Standby
−15
15
Unit
Note
%
9
Unit
Note
Relay Driver Output
(Relay 1 and 2)
Typ
Max
VOL, On voltage (each output)
Description
IOL = 30 mA
Test Conditions (See Note 1)
+0.25
+0.4
VOL, On voltage (each output)
IOL = 40 mA
+0.30
+0.8
IOH, Off leakage (each output)
VOH = +5 V
Zener breakover (each output)
IZ = 100 µA
Zener on voltage (each output)
IZ = 30 mA
Min
100
6.6
7.9
11
RELAY DRIVER SCHEMATIC
RYOUT2
RYOUT1
RYE
BGND
BGND
Note:
1.
Unless otherwise noted, test conditions are BAT1 = –75 V, BAT2 = –24 V, VCC = +5 V, VNEG = –5 V, RL = 600 Ω,
RDC1 = 80 kΩ, RDC2 = 20 kΩ, RD = 75 kΩ, no fuse resistors, CHP = 0.018 µF, CDC = 1.2 µF, D1 = D2 = 1N400x,
two-wire AC input impedance (ZSL) is a 600 Ω resistance synthesized by the programming network shown below.
RSGL = open, RSGH = open, RDCR1 = 15 kΩ, RDCR2 = 2 kΩ, CDCR = 10 nF, RRT1 = 430 kΩ, RRT2 = 12 kΩ, CRT = 1.5 µF,
RSLEW = 100 kΩ, CSLEW = 0.33 µF.
Figure 2. AC Input Impedance Programming Network
VTX
RT1 = 150 k Ω
CT1 = 60 pF
RT2 = 150 k Ω
RSN
RRX = 300 k Ω
12
Zarlink Semiconductor Inc.
V RX
V
µA
V
4
Le79R79
Data Sheet
2.
a. Overload level is defined when THD = 1%.
b. Overload level is defined when THD = 1.5%.
3.
Balance return signal is the signal generated at VTX by VRX. This specification assumes that the two-wire AC load impedance matches the
programmed impedance.
4.
Not tested in production. This parameter is guaranteed by characterization or correlation to other tests.
5.
This parameter is tested at 1 kHz in production. Performance at other frequencies is guaranteed by characterization.
6.
Group delay can be greatly reduced by using a ZT network such as that shown in Note 1 above. The network reduces the group delay to
less than 2 µs and increases 2WRL. The effect of group delay on linecard performance may also be compensated for by synthesizing
complex impedance with the QSLAC or DSLAC device.
7.
70 Vpk provides 50 Vrms with a crest factor of 1.25 to a load of 1400 Ω with 2 • Rf = 100, and Rline = 70 Ω (1570 Ω).
8.
Open Circuit VAB can be modified using RSGH.
9.
RD must be greater than 56 kΩ. See User-Programmable Components, on page 14. for typical value of RLTH.
10. Lower power is achieved by switching into low-battery state in standby. Standby loop current is returned to VBAT1 regardless of the battery
selected.
SLIC Device Decoding
(DET) Output
State
C3 C2 C1
Two-Wire Status
E1 = 1
E1 = 0
Battery
0
0
0
0
Open Circuit
Ring trip
Ring trip
1
0
0
1
Ringing
Ring trip
Ring trip
2
0
1
0
Active
Loop detector
Ground key
3
0
1
1
On-hook TX (OHT)
Loop detector
Ground key
4
1
0
0
Reserved
Loop detector
Ground key
B2EN = 1**
5
1
0
1
Standby
Loop detector
Ground key
VBAT1
6*
1
1
0
Active Polarity Reversal
Loop detector
Ground key
7*
1
1
1
OHT Polarity Reversal
Loop detector
Ground key
Note:
* Only –1 and –2 performance grade device supports polarity reversal.
** For correct ground-start operation using Tip Open, VBAT1 on-hook battery must be used.
13
Zarlink Semiconductor Inc.
B2EN
B2EN
Le79R79
Data Sheet
User-Programmable Components
Z T = 500 ( Z 2WIN – 2R F )
ZT is connected between the VTX and RSN pins. The fuse resistors are
RF, and Z2WIN is the desired 2-wire AC input impedance. When
computing ZT, the internal current amplifier pole and any external stray
capacitance between VTX and RSN must be taken into account.
ZL
1000 • Z T
Z RX = ------------- • ---------------------------------------------------G 42L Z T + 500 ( Z L + 2R F )
ZRX is connected from VRX to RSN. ZT is defined above, and G42L is the
desired receive gain.
2500
R DC1 + R DC2 = --------------I LOOP
RDC1, RDC2, and CDC form the network connected to the RDC pin.
ILOOP is the desired loop current in the constant-current region.
3000
R DCR1 + R DCR2 = ----------------------I RINGLIM
RDCR1, RDCR2, and CDCR form the network connected to the RDCR
pin.
See Application Circuit, on page 21. for these components.
R DC1 + R DC2
C DC = 19 ms • ----------------------------------R DC1 R DC2
R DCR1 + R DCR2
C DCR = ------------------------------------------- • 150 µs
R DCR1 R DCR2
CDCR sets the ringing time constant, which can be between 15 µs and
150 µs.
R D = R LTH • 12.67 for high battery state
RD is the resistor connected from the RD pin to GND and RLTH is the
loop-resistance threshold between on-hook and off-hook detection. RD
should be greater than 56 kΩ to guarantee detection occurs in the
Standby state. Choose the value of RD for high battery state; then use
the equation for RLTH to find where the threshold is for low battery.
Loop-Threshold Detect Equations
RD
- for high battery state
R LTH = -------------12.67
This is the same equation as for RD above, except solved for RLTH.
RD
- for Active state
R LTH = -------------11.37
For low battery, the detect threshold is slightly higher, which avoids
oscillating between states.
V BAT1 – 10
R LTH = ------------------------------ • R D – 400 – 2R F
915
RLTH Standby < RLTH Active VBAT1 < RLTH Active VBAT2, which
guarantees no unstable states under all operating conditions. This
equation shows at what resistance the Standby threshold is; it is
actually a current threshold rather than a resistance threshold, which is
shown by the VBAT dependency.
14
Zarlink Semiconductor Inc.
Le79R79
Data Sheet
DC FEED CHARACTERISTICS
Figure 3.
50
Typical VAB vs. IL DC Feed Characteristics
5) VAPPH
High Battery Anti-Sat
4) VASH
40
VAB
(Volts)
30
1) Constant-Current Region
20
3) VAPPL
Low Battery Anti-Sat
2) VASL
10
0
30
IL (mA)
R DC = R DC1 + R DC2 = 20 kΩ + 80 kΩ = 100 kΩ
( V BAT1 = – 75 V ,V BAT2 = – 24 V )
Notes:
1. Constant-current region:
2500
V AB = I L R L = ------------- R L ; where R L = R L + 2R F ,
RDC
3
2. Low battery
1000 • ( 104 • 10 + R SGL )
V ASL = ------------------------------------------------------------------ ; where RSGL = resistor to GND, B2EN = logic Low.
3
6720 • 10 + ( 80 • R SGL )
3
Anti-sat region:
3.
1000 • ( R SGL – 56 • 10 )
V ASL = --------------------------------------------------------------- ; where RSGL = resistor to VCC, B2EN = logic Low.
3
6720 • 10 + ( 80 • R SGL )
RSGL to VCC must be greater than 100 kΩ.
V APPL = 4.17 + V ASL
V APPL
I LOOPL = -----------------------------------------------------------------------------( R DC1 + R DC2 )
-------------------------------------- + 2R F + R LOOP
600
4. High battery
V ASH = V ASHH + V ASL
3
Anti-sat region:
1000 • ( 70 • 10 + R SGH )
V ASHH = ----------------------------------------------------------------------- ; where RSGH = resistor to GND, B2EN = logic High.
3
1934 • 10 + ( 31.75 • R SGH )
3
V ASHH
5.
V APPH
1000 • ( R SGH + 2.75 • 10 )
= ----------------------------------------------------------------------- ; where RSGH = resistor to VCC, B2EN = logic High.
3
1934 • 10 + ( 31.75 • R SGH )
RSGH to VCC must be greater than 100 kΩ.
= 4.17 + V ASH
V APPH
I LOOPH = -----------------------------------------------------------------------------( R DC1 + R DC2 )
-------------------------------------- + 2R F + R LOOP
600
15
Zarlink Semiconductor Inc.
Le79R79
Data Sheet
RING-TRIP COMPONENTS
R RT2 = 12 kΩ
C RT = 1.5 µF
V BAT1
R RT1 = 300 • CF • ------------------------------------------------------------------------------------------------------------------------------------------------ • ( R LRT + 150 + 2R F )
Vbat – 3.5 – ( 15 µA • 300 • CF • ( R LRT + 150 + 2R F ) )
where RLRT = Loop-detection threshold resistance for ring trip and CF = Crest factor of ringing signal (≈ 1.25)
RSLEW, CSLEW
Ring waveform rise time ≈ 0.214 • (RSLEW • CSLEW) ≈ tr.
For a 1.25 crest factor @ 20 Hz, tr ≈ 10 mS.
∴ (RSLEW = 150 kΩ, CSLEW = 0.33 µF.)
CSLEW should be changed if a different crest factor is desired.
Figure 4. Ringing Waveforms
Ringing Reference
(Input to R SLEW )
0
B(RING)
A(TIP)
Battery
This is the best time for switching
between Ringing and other states
for minimizing detect switching
transients.
Figure 5. Feed Programming
A (TIP)
a
RSN
IL
RL
RDC1
SLIC
b
RDC2
B (RING)
RDC
Feed current programmed by R
DC1
and R DC2
16
Zarlink Semiconductor Inc.
CDC
Le79R79
Data Sheet
TEST CIRCUITS
Figure 6. Two-to-Four-Wire Insertion Loss
A (TIP)
VTX
RL
SLIC
2
V AB
VL
RT
AGND
RL
RRX
2
RSN
B (RING)
IL2-4 = 20 log(V TX / V AB )
Figure 7.
Four-to-Two-Wire Insertion Loss and Four-to-Four-Wire Balance Return Signal
A (TIP)
VTX
SLIC
V AB
RT
RL
AGND
RRX
B (RING)
RSN
V RX
IL4-2 = 20 log(V AB / V RX )
BRS = 20 log(V TX / V RX )
Figure 8.
1
ωC
Longitudinal Balance
RL
2
S1
VTX
A (TIP)