Features

Transformerless 2W to 4W conversion

Controls battery feed to line

Programmable line impedance

Programmable network balance impedance

Off-hook and dial pulse detection

Protects against GND short circuit

Programmable gain

Programmable constant current mode with
constant voltage fold over

Transformerless balanced ringing with
automatic ring trip circuit. No mechanical relay

Supports low voltage ringing

Line polarity reversal

On-hook transmission

Power down and wake up capability

Meter pulse injection

Ground Key detection

Applications

Line interface for:
·

PABX

Intercoms

Key Telephone Systems

Control Systems

Description

The Mitel MT91610, with an external bipolar driver
(Figure 4), provides an interface between a switching
system and a subscriber loop. The functions
provided by the MT91610 include battery feed,
programmable constant current with constant voltage
fold over for long loop, 2W to 4W conversion, off-
hook and dial pulse detection, direct balance ringing
with built in ring tripping, unbalance detection, user
definable line and network balance impedance's and
gain, and power down and wake up. The device is
fabricated as a CMOS circuit in a 36 pin QSOP
package.

Figure 1 - Functional Block Diagram

RING

Tip/Ring Drive

Controller

Audio Gain & Network

Balance Circuit

2 W to 4 W

Conversion & Line

Impedance

Line

Reverse

Line Sense

Over-Current

Protection Circuit

Ring Drive
Controller

Loop Supervision

TIP

RF1, RF2

CP5

VEE

GND

VDD

CP3

CP2

SHK

VREF

GTX1

GTX0

CP6

Driver

DCRI

VBAT

ESI

ESE

CP4

CP7

CP1

Package Information

MT91610AQ

36 Pin QSOP Package

-40

C to +85

MT91610

Analog Ringing SLIC

Preliminary Information

DS5181

ISSUE 2

February 2000

MT91610

Preliminary Information

Figure 2 - Pin Connections

Pin Description

Pin #

Name

Description

VDD

Positive supply rail, +5V.

Tip Drive (Output). Controls the Tip transistor. Connects 150nF cap to GND.

TF1

Tip Feed 1 (Output). Connects to the Tip transistor and to TIP via the Tip feed resistor.

No Connection Left open

Tip

Tip. Connects to the TIP lead of the telephone line.

VREF

Reference Voltage (Input). Used to set the subscribers loop constant current. A 0.1uF
cap should be connected between this pin and GND for noise decoupling.

Line Reverse (Input). This pin should be set to 0V for NORMAL polarity. Setting the pin
to +5V reverses the polarity of Tip and Ring

Ring

Ring. Connects to the RING lead of the telephone line

RF1

Ring Feed 1 (Output). Connects to the RING lead via the Ring feed resistor

No Connection Left open

Ring Drive (Output). Controls the Ring transistor. Connects 150nF cap to GND.

CP1

CP1. A 220nF capacitor should be connected between this pin and pin 13

CP2

CP2. A 330nF capacitor for loop stability is connected between this pin and pin 14

CP3

CP3. A 330nF capacitor for loop stability is connected between this pin and pin 13

CP4

CP4. A 100nF cap should be connected between this pin and GND

ESE

External Signal Enable (Input). A logic '1' enable the MPI (Meter Pulse Input) to Tip /
Ring. This pin should be set to logic '0' when not used.

Power Down (Input). A logic '1' power down the device. This pin should be set to logic '0'
for normal operation.

DCRI

DC voltage for Ringing Input (Input) The positive voltage supply for balance ringing.
The input DC voltage range is from 0V to +72V.

AGND

Analog Ground. 4 Wire Ground, normally connected to system ground.

VREF

CP7

VEE

RING

GTX0

TIP

RF1

TF1

VDD

CP1
CP2

CP3

SHK
VBAT

RC
CP6

GTX1
ESI

CP4

ESE

DCRI

CP5

AGND

Preliminary Information

MT91610

Line Impedance Node 1. A resistor of scaled value "k" is connected between Z1 and Z2.
This connection can not be left open circuit.

CP5

Line Impedance AC couple. A 0.1uF cap must be connected between this pin and Z1
(pin 16)

Line Impedance Node 2. This is the common connection node between Z1 and Z3.

Line Impedance Node 3. A network either resistive or complex of scaled value "k" is
connected between Z3 and Z2. This connection can not be left open circuit.

GTX0

Gain Node 0. This is the common node between Z3 and VX where resistors are
connected to set the 2W to 4W gain.

Transmit Audio. 4W analog signal from the SLIC.

ESI

External Signal Input. 12 / 16 KHz signal input

GTX1

Gain Node 1. The common node between VR and the audio input from the CODEC or
switching network where resistors are fitted to sets the 4W to 2W gain

Receive Audio. 4W analog signal to the SLIC.

CP6

Ringing Cap. A 0.47uF cap should be connected between this pin and GND for ringing
voltage filtering.

Ringing Control. An active high (+5V) on this pin will set up the DC feed and gain of the
SLIC to apply 20 Hz ringing. When low (0V) set the SLIC in normal constant current mode
of operation.

UnBalance Detect. To indicate an offset current between Tip and Ring

VBAT

VBAT. The negative battery supply, typically at -48V

SHK

Switch Hook. This pin indicates the line state of the subscribers telephone. The output
can also be used for dial pulse monitoring. This pin is active high

CP7

Deglitching Cap. A 33nF should be connected between this pin and GND

Ringing Voltage. 20 Hz sinusoidal or square wave AC in for balance ringing

VEE

Negative supply rail, -5V.

Pin Description (continued)

Pin #

Name

Description

Functional Description

Refer to Figure 4 for MT91610 components
designation.

The MT91610, with external bipolar transistors,
functions as an Analog Line SLIC for use in a 4 Wire
switched system. The SLIC performs all of the
BORSH functions whilst interfacing to a CODEC or
switching system.

2 Wire to 4 Wire conversion

The SLIC performs 2 wire to 4 wire conversion by
taking the 4 wire signal from an analog switch or
voice CODEC, and converting it to a 2 wire
differential signal at Tip and Ring. The 2 wire signal
applied to tip and ring by the phone is converted to a

4 wire signal, which is the output from the SLIC to
the analog switch or voice CODEC.

Gain Control

It is possible to set the Transmit and Receive gains
by the selection of the appropriate external
components.

The gains can be calculated by the following
formulae:

2W to 4W gain
Gain 2 - 4 = 20 Log [ R8 / R7]

4W to 2W gain

Gain 4 - 2 = 20 Log [0.891 * [R10 / R9)]

MT91610

Preliminary Information

Impedance Programming

The MT91610 allows the designer to set the device's
impedance across TIP and RING, (Z

), and

network balance impedance, (Z

), separately with

external low cost components.

The impedance (Z

) is set by R4, R5, whilst the

network balance, (Z

), is set by R6, R8, (see Figure

4.)

The network balance impedance should be
calculated once the 2W - 4W gain has been set.

Line Impedance

For optimum performance, the characteristic
impedance of the line, (Z

), and the device's

impedance across TIP and RING, (Z

), should

match. Therefore:

= Z

The relationship between Z

and the components

that set Z

is given by the formula:

/ ( Ra+Rb) = kZ

/ R4

where kZ

= R5

Ra = Rb

The value of k can be set by the designer to be any
value between 20 and 250. R4 and R5 should be
greater than 50k

Network Balance Impedance

The network balance impedance, (Z

), will set the

transhybrid loss performance for the circuit. The
transhybrid loss of the circuit depends on both the 4 -
2 Wire gain and the 2 - 4 Wire gain.

The method of setting the values for R6 (or Z6... it
can be a complex impedance) is given as below:

R6 = R7 * (R9 / R10) * 2.2446689 * ( Z

/ Z

+ Z

)

Please note that in the case of Z

not equal to Z

(the THL compromized case) R6 is a complex
impedance. In the general case of Z

matches to Z

(the THL optimized case) R6 is just a single resistor.

Loop Supervision

The Loop Supervision circuit monitors the state of
the phone line and when the phone goes "Off Hook"
the SHK pin goes high to indicate this state. This pin
reverts to a low state when the phone goes back "On
Hook" or if the loop resistance is too high (>2.3K

)

When loop disconnect dialing is being used, SHK
pulses to logic 0 indicate the digits being dialled.
This output should be debounced.

Constant Current Control & Voltage
Fold Over Mode

The SLIC employs a feedback circuit to supply a
constant feed current to the line. This design is
accomplished by sensing the sum of the voltages
across the feed resistors, Ra and Rb, and comparing
it to the input reference voltage, Vref, that
determines the constant current feed current.

By using a resistive divider network, (Figure 3), it is
possible to generate the required voltage to set the
I

LOOP

. This voltage can be calculated by the formula:

LOOP

= [ G * 5] * 3

(Ra +Rb)

where,

G = R2 / (R1 + R2)
I

LOOP

is in Ampere.

R1= 200K

From Figure 3 with Ra = Rb = 100

For I

LOOP

= 20mA, R2 = 72.73 K

For I

LOOP

= 25mA, R2 = 100 K

For I

LOOP

= 30mA, R2 = 133.33 K

Figure 3 - Loop Setting

For convenience, a graph which plots the value of
R2 (K

) versus the expected loop current is shown

in Figure 6.

R2
**k

REF

MT91610

+5V

0.1uF

** See Figure 6

200K

Preliminary Information

MT91610

As +5V is used as the reference voltage to generate
the loop current, any noise on the +5V rail will
deteriorate the PSR (Power Supply Rejection)
parameter of the SLIC. It is therefore important to
decouple +5V to GND. A 0.1uF cap at Vref pin (pin6)
is recommended.

The MT91610 operating current mode is
recommended to be between 20mA and 30mA. The
device will automatically switch to voltage hold over
mode should an unexpected long loop situation
occur for a given programmed loop current. The
lowest operational current should be 16mA with
VBAT set at -48V. A typical Operating Current versus
Loop Resistance with VBAT at -48V is shown in
Figure 7.

UD & Line Drivers Overcurrent
Protection

The Line Drivers control the external Battery Feed
circuit which provide power to the line and allows bi-
directional audio transmission.

The loop supervision circuitry provides bias to the
line drivers to feed a constant current. Overcurrent
protection is done by the following steps:

(A) External bipolar transistors to limit the current of
the NPN drivers to 50mA (Figure 5).

(B) The local controller should monitor the
Unbalance Detection output (UD) for any extended
period of assertion (>5 seconds). In such case the
controller should power down the device by asserting
the PD pin, and polls the device every 5 seconds.

The UD output can be used to support GND START
LOOP in a PaBX operation.

Please note that this UD output should be
disregarded and masked out if RC pin is active (ie
set to +5V).

Powering Up / Down Sequence

AGND is always connected
Powering Up: +5V, -5V, VBAT
PD to +5V for 100ms; PD to 0V
Powering Down: VBAT, -5V, +5V

Balanced Ringing & Automatic Ring
Tripping

Balanced Ringing is applied to the line by setting the
RC to +5V (pin 25) and connecting ringing signal
(20Hz) to RV (pin 35) as shown in Figure 4. A
1.2Vrms input will give approximately about 60Vrms
output across Tip and Ring, sufficient for short loop
SLIC application. The SLIC is capable of detecting
an Off Hook condition during ringing by filtering out
the large A.C. component. A 0.47uF cap should be
connected to pin CP6 (pin 29) to form such filter.
This filter allows a true Off Hook condition to be
monitored at pin SHK (pin 33). When an Off Hook
condition is detected by the SLIC, it will remove the
20Hz AC ringing voltage and revert to constant
current mode. The local controller will, however, still
need to deselect RC (set it to 0V).

The MT91610 supports short burst of ringing
cadence. A deglitching input (CP7) is provided to
ensure that the SHK pin is glitch free during the
assertion and de-assertion of RC. A 33nF cap
should be connected at this pin to GND.

A positive voltage source is required to be
connected to the pin DCRI (Figure 5) for normal
Ringing generation. The SLIC can perform ringing
even with the DCRI input connected to 0V. However,
it does require the VBAT to be lower than -48V (ie at
-53V or lower) and the 20Hz AC input should be a
square wave at 2Vrms.

Line Reversal

The MT91610 can deliver Line Reversal, which is
required in operation such as ANI, by simply setting
LR (pin 7) to +5V. The device transmission
parameters will cease during the reversal. The LR
(pin 7) should be set to 0V for all normal loop
operations.

Power Down And Wake Up

The MT91610 should normally be powered down to
conserve energy by setting the PD pin to +5V. The
SHK pin will be asserted if the equipment side (2
wire) goes off hook. The local controller should then
restore power to the SLIC for normal operations by
setting the PD pin to 0V.

Please note that there will be a short break (about
80ms) in the assertion time of SHK due to the time
required for the loop to power up and loop current to
flow. The local controller should be able to mask out
this time fairly easily.

MT91610

Preliminary Information

Meter Pulse Injection

The MT91610 provides a gain path input (ESI) for
meter pulse injection and an independent control
logic input (ESE) for turning the meter pulse signal
on and off.

Additional circuit can be used to ensure good
cancellation of meter pulse signal (Figure 4) should it
becomes audible at the 4 wire side. Usually, the
optional circuit is not required.

Gain (meter pulse) = 20 Log [0.891 * (R10 / R11)]

Components Selection

Feed Resistors

The selection of feed resistors, Ra and Rb, can
significantly affect the performance of the MT91610.
The value of 100

is used for both Ra and Rb.

The resistors should have a tolerance of 1% (0.1%
matched) and a power rating of 0.5 Watt.

Calculating Components Value

There are five parameters a designer should know
before starting the component calculations. These
five parameters are:

1) characteristic impedance of the line Z

2) network balance impedance Z

3) value of the feed resistors (Ra and Rb)
4) 2W to 4W transmit gain
5) 4W to 2W receive gain

The following example will outline a step by step
procedure for calculating component values. Given:

= 600

, Z

= 600

, Ra=Rb= 100

Gain 2 - 4 = -6dB, Gain 4 - 2 = -1 dB

Step 1: Gain Setting (R7, R8, R9, R10)

Gain 2 - 4 = 20 Log [ R8 / R7]
-6 dB = 20 Log [R8 / R7]

choose R7 = 300k

, R8 = 150k

Gain 4 - 2 = 20 Log [0.891 * [R10 / R9)]
-1 dB = 20 Log [0.891 * [R10/ R9)]

choose R9 = 200k

, R10 = 200k

Step 2: Impedance Matching (R4, R5)

/ ( Ra+Rb) = kZ

/ R4 where kZ

= R5

R5 / R4 = 3

choose R4 = 100k

=> R5 = 300k

Step 3: Network Balance Impedance (R6)

Optimized Case Z

= Z

R6 = R7 * (R9 / R10) * 2.2446689 * ( Z

/ Z

+ Z

)

R6 = 300k

* (1) * 1.1223344

= 336.7k

Step 4: The Loop Current (R2)

In order to remain in constant current mode during
normal operation, it is necessary that the following
equation holds:

{| I * Zt |} V < { | VBAT | - 6*VREF - 2} V
where,
I = Desirable Loop Current
Zt = Ra + Rb + maximum loop impedance
VBAT = Battery voltage
VREF= DC voltage at VREF pin

Given the parameters as follows:
Ra = Rb = 100

Expected maximum loop impedance = 1.6k

(

including Ra and Rb)

Desirable Loop Current = 20mA
6*Vref=8V
Then | VBAT | (min) = 1600 * 0.020 +10 = 42V

Assume that the VBAT of 42V is available, then read
the value of R2 from Figure 6, which is 50k

Step 5: Calculation Of Non-Clipping Sinusoidal
Ringing Voltage At Tip Ring (VTR)

Assume the Ringing Current is less than 40mA, the
ringing voltage (20Hz) at Tip and Ring is given as:

VTR (rms) = 0.707 * {| VBAT | + VDCRI - (15.6 *
VREF)}

VDCRI= Positive DC voltage at DCRI pin

VBAT = Negative Battery voltage
VREF= Positive DC voltage at VREF pin

AC voltage at the RV input pin is therefore
RV (rms)~= VTR (rms) / 50

Preliminary Information

MT91610

Figure 4 - Typical Application with a Resistive 600 ohm Line Impedance

CP5

GTX0

ESI

GTX1

+5V

C10

TF1

Vdd

Vee

UD 31

VBAT

SHK

VBAT

CP6

AGND

CP7

DCRI

CP4

CP3

TIP

RING

RF1

VREF2

C11

C12

C13

-5V

VBAT

+5V

DCRI_IN

TR_DRIVER_610B

R11

R10

+5V

CP2

CP1

ESE

Ground (Earth)

NO CONNECT

SWITCH HOOK

R13

SHK

C15

C14

UNBALANCE DETECTION

ESE

POWER DOWN

LINE REVERSE

RING CONTROL

VR_IN

VX_OUT

ESI

SHK

VBAT_IN

TIP

RING VOLTAGE

-5V

TF_BR

RF_BR

PR1

ESE

* See Functional Description Meter Pulse Injection

R16

D1**

** Optional

MT91610

Preliminary Information

Component List

R11

100k

See Figure 6

R1,9,10 =

200k

100k

R5,7,16 =

300k

336k7

150k

R13

51k

C1,10

330nF, 5%

C2,4,5,7,8 = 100nF, 5%
C3

470nF, 5%

4.7uF, 5%

10nF, 5%

C11

33nF, 5%

C12

100nF, 5%

C13

220nF, 5%

C14,15

150nF, 5%

1N5819 Schottky Diode (Optional)

All resistors are 1/4W, 1% unless otherwise indicated.

PR1

This device must always be fitted to ensure damages does not occur from inductive loads.
For simple applications PR1 can be replaced by a single TVS, such as 1.5KE220C, across tip

and ring.

For applications requiring lightning and mains cross protection further circuitry will be required
and the following protection devices are suggested:
P2353AA, P2353AB (Teccor), THBT20011, THBT20012, THBT200S (SGS-Thomson),
TISP2290, TSSP8290L (T.I.)

TF_BR,RF_BR= Circuit Breaker

Preliminary Information

MT91610

Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied.

Note 1: Refer to Figure 3 & 6 for appropriate biasing values
Note 2: Tip and Ring drivers to be limited to about 50mA externally (Figure 5). If the UD pin is asserted for longer than 5 seconds, then
PD should be asserted to power down the device. The device should then be checked (by de-asserting PD) every 5 seconds.

Typical Figures are at 25°C with nominal supply voltages and are for design aid only

Note 3: For a 1.2Vrms 20Hz input at RV terminal (Figure 4) and with RC pin set to +5V.
Note 4: Refer to Figure 3 & 6 for biasing values

Absolute Maximum Ratings*

Parameter

Sym

Min

Max

Units

Comments

DC Supply Voltages

BAT

-0.3

+0.3
+0.3

+6.5

-6.5

-72

V
V
V

Ringing Voltages

RING

RMS

Differentially across Tip &
Ring for a 1.5Vrms input
at RV (Figure 4)

Voltage setting for Loop Current

REF

Note 1

Overvoltage Tip/GND Ring/GND,
Tip/Ring

200

MAX 1ms (with power on)

Ringing Current

RING

Tip / Ring Ground over-current

Note 2

Storage Temp

STG

-65

+150

°C

Package Power Dissipation

DISS

0.10

+85°C max, V

BAT

= -48V

ESD maximum rating

500

Recommended Operating Conditions

Parameter

Sym

Min

Typ

Max

Units

Test Conditions

Operating
Supply Voltages

BAT

DCRI

4.75

-5.25

-72

5.00

-5.00

-48

5.25

-4.75

-22

V
V
V
V

50mA current capability

Ringing Voltage

RING

RMS

Note 3

Voltage setting for Loop Current

REF

1.67

LOOP

= 25mA,

VBAT = -48V
Note 4

Operating Temperature

-40

+25

+85

°C

MT91610

Preliminary Information

Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.

Typical Figures are at 25

C with nominal

5V and are for design aid only.

DC Electrical Characteristics

Characteristics

Sym

Min

Typ

Max

Units

Test Conditions

Supply Current

BAT

8
6

mA
mA
mA

PD= 0V

BAT

= -48V

BAT

~ l

LOOP

+ 3 mA

Supply Current

BAT

300
300

1.8

uA
uA

PD = 5V
V

BAT

= -48V

Constant Current Line
Feed

LOOP

REF

=1.67V

Operating Loop Constant
Current Mode
(including the DC
resistance of the
Telephone Set)

LOOP

1600

700

LOOP

= 20mA

BAT

= -48V

LOOP

= 20mA

BAT

= -22V

Off Hook Detection
Threshold

RC, LR
Input Low Voltage
Input High Voltage

4.5

0.5

V
V

= -1

= 1

PD, ESE
Input Low Voltage
Input High Voltage

4.5

0.5

V
V

= -1

= 1

SHK
Output Low Voltage
Output High Voltage

2.7

0.4

V
V

= 8mA

= -1mA

UnBalance Detection
Threshold

UD
Output Low Voltage
Output High Voltage

2.7

0.4

= 0.3mA

= -0.3mA

Dial Pulse Distortion

Preliminary Information

MT91610

Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.

Typical Figures are at 25

C with nominal

5V and are for design aid only.

Note 5: Refer to Figure 4 & 5 for set up and components value.
Note 6: TLRR is measured from the time when the LR pin is set to 0V (de-selected), to the time when the loop current is within 10% of
its programmed steady state value.

AC Electrical Characteristics

Characteristics

Sym

Min

Typ

Max

Units

Test Conditions

Ring Trip Detect Time

200

300Hz to 3k4Hz

Note 5

Impedance (2W)

600

Return Loss (2W)

Transhybrid Loss

THL

Output Impedance at VX

AC small signal

Gain 4 to 2 Wire @ 1kHz

-1.5

-1

-0.5

Note 5

Gain Relative to 1kHz

0.15

300 - 3400Hz

Gain 2W to VX @ 1kHz

-0.5

0.5

Note 5

Gain Relative to 1kHz

0.15

300Hz to 3.4KHz

Longitudinal to Metallic Balance
at 2W

LCL

300Hz to 3.4KHz

Total Harmonic Distortion
@2W
@VX

THD

0.3
0.3

1.0
1.0

%
%

1Vrms, 1kHz @ 2W
1Vrms, 1KHz @ VR

Common Mode Rejection
2 Wire to Vx

CMR

Input 0.5Vrms, 1KHz

Idle Channel Noise
@2W
@VX

12
12

dBrnC
dBrnC

Cmessage Filter Fig. 4
Cmessage Filter Fig. 4

Power Supply Rejection
Ratio at 2W and VX
Vdd
Vee

PSR

23
23

dB
dB

0.1Vp-p @ 1kHz

Line Reversal Recovery Timing

TLRR

Note 6

MT91610

Preliminary Information

QSOP - Quad Shrink Outline Package

Dim

36-Pin

Dim

36-Pin

Min

Max

Min

Max

.096

(2.44)

.104

(2.64)

.0315 inches (ref)

0.80mm

.004

(0.10)

.012

(0.30)

.398

(10.11)

.414

(10.51)

.011

(0.26)

.020

(0.51)

0.16

(0.40)

.050

(1.27)

.0091

(0.23)

.0125

(0.32)

.598

(15.20)

.606

(15.40)

.025

(0.63)

.035

(0.89)

.291

(7.40)

.299

(7.60)

.0335 inches (ref)

0.85

Pin #1

GAGE
PLANE

(.014)

0.335

0.51 x 45

(.020)

0.20

.008

0.63

(.025)

.004

0.10

Notes:

1. Lead Coplanitary should be 0 to 0.10mm (.004") max
2. Package surface finishing

(2.1) Top Matte: (Charmilles #18-30)
(2.2) All Sides: (Charmilles #18-30)
(2.3) Bottom Matte: (Charmilles #18-30)

3. All dimensions excluding mold flashes
4. Max. deviation of center of package and center of leadrame to be 0.10mm (.004")
5. Max. misalignment between top and bottom center of package to 0.10mm (.004")
6. End flash from the package body shall not exceed 0.152 (.006") per side (D)
7. Dimension B shall not include dambar protrusion/intrusion and solder coverage.
8. Not to scale
9. Dimension in inches
10.Dimensions in (millimeters)

TECHNICAL DOCUMENTATION - NOT FOR RESALE

World Headquarters - Canada

Tel: +1 (613) 592 2122

Fax: +1 (613) 592 6909

North America

Asia/Pacific

Europe, Middle East,

Tel: +1 (770) 486 0194

Tel: +65 333 6193

and Africa (EMEA)

Fax: +1 (770) 631 8213

Fax: +65 333 6192

Tel: +44 (0) 1793 518528

Fax: +44 (0) 1793 518581

http://www.mitelsemi.com

Information relating to products and services furnished herein by Mitel Corporation or its subsidiaries (collectively "Mitel") is believed to be reliable. However, Mitel assumes no
liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any such information, product or service or for any infringement of
patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or
service conveys any license, either express or implied, under patents or other intellectual property rights owned by Mitel or licensed from third parties by Mitel, whatsoever.
Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Mitel, or non-Mitel furnished goods or services may infringe patents or
other intellectual property rights owned by Mitel.

This publication is issued to provide information only and (unless agreed by Mitel in writing) may not be used, applied or reproduced for any purpose nor form part of any order or
contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this
publication are subject to change by Mitel without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or
service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific
piece of equipment. It is the user's responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or
data used is up to date and has not been superseded. Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in
any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Mitel's
conditions of sale which are available on request.

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: MT91610

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: MT91610