ground loop break circuits and their operations

8/2/2019 Ground Loop Break Circuits and Their Operations

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Application ReportSLOA143 October 2009

Ground Loop Break Circuits and Their OperationStephen Crump .......................................................................................................... Audio Products

ABSTRACTGround loops can be introduced when different components in audio systems are connected with standardaudio cables, and these loops can cause annoying interference. In many cases, the interference can bereduced significantly with a "ground loop break" (GLB) circuit including a low-value resistor and differentialamplifiers. This paper explains this approach and how to design a GLB circuit.

Contents

1 Introduction .................................................................................................................. 12 GLB Output Circuit .......................................................................................................... 13 GLB Input Circuit ............................................................................................................ 24 How GLB Circuits Work .................................................................................................... 25 Ground Loop Noise Reduction at an Output ............................................................................ 46 Ground Loop Noise Reduction at an Input .............................................................................. 57 Potential Crosstalk Issue in GLB Headphone Amplifier ............................................................... 58 Potential Power Loss in GLB Headphone Amplifier .................................................................... 7Appendix A GLB OUTPUT CIRCUIT IMPLEMENTED WITH TPA6132A2 ............................................... 9Appendix B GLB CIRCUIT IMPLEMENTATIONS .......................................................................... 10Appendix C HOW GROUND LOOP INTERFERENCE OCCURS ........................................................ 13

1 Introduction

Connecting a standard audio cable between 2 grounded components in an audio system can result inaudible and annoying interference. When this happens, it is because the cable shield has introduced whatis usually called a "ground loop", an extra ground connection between 2 components with different internalground potentials. The difference between these potentials occurs along the audio cable shield (groundconnection). It is indistinguishable from the normal signal, so it creates interference.

Fortunately, the interference may be reduced significantly by inserting a low resistance between theground of one of the 2 components and the ground of its audio jack and using differential amplifiers tobridge the ground potential difference. This is called a "ground loop break" (GLB) circuit. This paperdescribes GLB circuits and explains how these circuits work, what the possible reduction might be, andhow to avoid a potential crosstalk problem. Appendix C describes how the interference occurs.

2 GLB Output Circuit

The following schematic illustrates a GLB output for driving line inputs or headphones. The circuit uses alow value GLB resistor, Rgbk, typically 5 to 20 ohms, plus two differential amplifiers. ( SGND) is the groundreference of the differential amplifier inputs. Power supply, charge pump and logic pins and circuits areomitted for simplicity (for a specific device, refer to the data sheet and EVM users guide). Gain of thedifferential amplifiers is set as required for the application.

1SLOA143 October 2009 Ground Loop Break Circuits and Their Operation

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AUDIO

SOURCE

Rgbk

GLBLINEor

HEADPHONE

OUTPUT

+

-

+

-

5W

(SGND)

TONEXTSTAGE

Rgbk

GLBLINEINPUT

+

-

+

-

(SGND)

5

GLB Input Circuit www.ti.com

This circuit may be implemented very easily with Texas Instruments TPA6132A2 or several other devicesin the TPA613x family. An implementation with TPA6132A2 is shown in Appendix A. These devices aregood choices for GLB circuits because they provide compact, integrated solutions with high CMRR.Members of the DRV60x family and TPA4411 are also good candidates for use in GLB output circuits.(For additional implementations of GLB circuits, see Appendix B.)

3 GLB Input Circuit

The following schematic illustrates a GLB line input. As before, the circuit uses a low value GLB resistor,Rgbk, typically 5 to 20 ohms, plus two differential amplifiers. (SGND) is the ground reference of thedifferential amplifier inputs. Again, power supply, charge pump and logic pins and circuits are omitted forsimplicity; and, gain of the differential amplifiers is set as required for the application.

Members of the TPA613x and DRV60x families and TPA4411 are good candidates for use in GLB inputcircuits. (Again, for additional implementations of GLB circuits, see Appendix A.)

4 How GLB Circuits Work

The following schematic illustrates an audio system with a ground loop between 2 components. Theschematic includes an audio source (for example, MP3 or CD player, computer, or navigation device), an

audio receiver (for example, stereo system, TV, or vehicle audio panel or head unit), and an audio cableconnected between them to form the ground loop. The ground reference for the system is taken to be theground of the power source, Gb. The audio source and receiver components are at different groundpotentials Gs and Gr with respect to Gb.

2 Ground Loop Break Circuits and Their Operation SLOA143 October 2009



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AUDIOSOURCE

Gs

AUDIOCABLE

AUDIO RECEIVER

System

Outputs

GrG b

(Gs Gr )

Gx ZcGc =

(Zc + Zx)

AUDIOSOURCE

AUDIOCABLE

AUDIO RECEIVER

SystemOutput

Zc= sleeve impedance

G x( =Gs Gr)

Va

Zx =groundimpedance

Zx

Zc

OUTPUT

JACK

INPUT

JACK

_Gx*Zc _

(Zc+Zx)Gc= Vr=Va+Gc;

Gcis INTERFERENCE

www.ti.com How GLB Circuits Work

The schematic is simplified below to make analysis easier. The simplified circuit is monaural, and theground reference is shifted to the audio receiver, since this is the device that produces the audibleinterference caused by the ground loop. Zc is the total of audio cable sleeve impedance and jack contact

impedance, and Zx is the total impedance in the ground connections between the source and the receiver.Gc and Gx are ground potentials between the source and receiver and at the source end of the audiocable and jacks. Gx = Gs Gr in the preceding schematic.

Va is the intended output from the audio source to the receiver, relative to its local ground, but the inputsignal relative to receiver local ground is (Va + Gc), where

(1)

is the noise at source local ground relative to receiver local ground.

Gc, part of the ground potential Gx, appears across the audio jack sleeve contacts and the audio cableshield, adding interference to the input to the receiver. Reducing this requires 2 steps.

Insert a resistance greater than the shield impedance of the audio cable between local ground andaudio cable ground in either the source or the receiver. This will reduce the noise potential across theaudio cable ground, because most of the noise will appear across the resistor.

Add differential amplifiers to reproduce the desired signal directly at the output jack to the audio cableor directly from the input jack at the audio cable, bridging the ground potential difference.

The resistance inserted in series with the audio cable shield is called a "ground loop breaking" resistor,Rgbk. (More properly its a "ground noise reduction" resistor, but "ground loop breaking" is a more popularand familiar description.) The resistor can be inserted at either the source or the receiver, so it isnecessary to consider both cases.


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AUDIOSOURCE

AUDIOCABLE

AUDIO RECEIVER

System

Output

G x

Va

Vr=Va+ Gc;

GcisREDUCEDinterference

Zx

Zc

____Gx*Zc____

(Zc+Zx+Rgkb)

Rgbk

(SGND)

OUTPUT

JACK

INPUT

JACK

Gc=

Gx Zc

(Zc + Zx)

Gx Zc

(Zc + Zx + Rgbk)

(Zc + Zx)

(Zc + Zx + Rgbk)

(200 m + 200 m)

(200 m + 200 m + 5)

0.4= 0.074 or -23dB

5.4

Ground Loop Noise Reduction at an Output www.ti.com

5 Ground Loop Noise Reduction at an Output

The revised schematic below includes Rgbk inserted between local source ground and the sleeve (groundcontact) of the output jack to the audio cable, and it includes a differential amplifier to transmit the originalsource signal to the output jack.

The original interference is

(2)

Interference with GLB is

(3)

So the modified circuit reduces interference by the following ratio.

Interference reduction equals

(4)

The reduction can be quantified with typical figures for Zc and Zx and a choice of Rgbk. Zc, which includes the impedance of the cable sleeve and the contact impedances in the output and

input jacks, can range from 100 m to nearly 1 . It is typically 200 to 300 m. Cable sleeveimpedances appear fairly consistent around 100 m. Contact impedances range from less than100 m per pair in higher quality jacks to nearly 1 in low cost PCB mount jacks.

Zx appears to be typically around 200 m.

Rgbk is typically chosen in the range 5 to 20 .

Then, for Zc = 200 m, Zx = 200 m and Rgbk = 5 , the reduction is the following.


(5)

Or, interference reduction equals

(6)

A reduction of 23 dB is very audible and provides a great improvement.




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AUDIOSOURCE

AUDIO CA BLE

AUDIO RECEIVER

System

Output

G x

Va

Zx

Zc Rgbk

OUTPUT

JACK

INPUT

JACK

Vr=Va Gc;

GcisREDUCEDinterference

____Gx*Zc____

(Zc+Zx+Rgkb)Gc=

Gx Zc

(Zc + Zx)

-Gx Zc

(Zc + Zx + Rgbk)

(Zc + Zx)

(Zc + Zx + Rgbk)

STEREO AUDIOSOURCE

Rgbk

HEADSET

LOADS

FeedbackGain Af~ =1G c

Zb

ZaChn. B

Chn. A

Vb

V a

Za =Z b =Zhs,

ofcourse!

(Vi)

www.ti.com Ground Loop Noise Reduction at an Input

6 Ground Loop Noise Reduction at an Input

The revised schematic below includes Rgbk inserted between local receiver ground and the sleeve(ground contact) of the input jack to the audio cable, and it includes a differential amplifier to transmit theoriginal source signal to the rest of the receiver circuits.

The original interference is

(7)

Interference with GLB is

(8)

So the modified circuit reduces interference by the following ratio. (The sign of the interference isirrelevant, so it is omitted here.)


(9)

The reduction is the same as the reduction with a GLB output, and it can be quantified the same way.

7 Potential Crosstalk Issue in GLB Headphone Amplifier

A potential issue in a GLB headphone amplifier is elevated crosstalk. The crosstalk is created by thesignal developed across Rgbk by currents flowing through low-impedance headphone loads. Theschematic below expands our previous circuit to a full stereo system for considering this effect. In theschematic channel A has an input and channel B does not.

Feedback gain Af from Rgbk back through the amplifiers to their outputs is intended to be exactly 1, tooffset voltage across Rgbk. But Af has some error. If this error is small, there will be no problem, but if it islarge, Rgbk will create crosstalk.




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Va RgbkGc = = Va K(2 Rgbk + Zhs)

RgbkK ==

(2 Rgbk + Zhs)

5K = = 0.12

(2 5 + 32)

A:CMR Configuration

CMR== ( Vo.C / Vi.C )

Output

differential

reference

Vo.C

Vi.C

B: GainErrorConfiguration

GainError== (Vi.G Vo.G)/Vi.G

Vo. G

Vi. G

Potential Crosstalk Issue in GLB Headphone Amplifier www.ti.com

Crosstalk can be analyzed using the schematic above and the following definitions.

is the fractional error in Af (Af == 1+).

Va is output voltage of Chn.A and Vb is output voltage of Chn.B.

Zhs is headset impedance per channel.

Signal across Rgbk is

(10)

Where

(11)

Then Vb = Va K , and relative crosstalk Xtk = K .

Of course, it is necessary to understand to quantify the result. This will vary with different amplifierconfigurations.

Many amplifiers use opamps and discrete 1% resistors to implement differential inputs. Generally amplifiercommon-mode rejection is very high, and amplifier operation is very linear, so gain error is governed byresistor tolerance. For these amplifiers, the gain error can be as high as 2 to 4%, although typically thegain error is likely to be less than 1%, or 40dB. The calculation that follows uses = 1%, Rgbk = 5 andZhs = 32.

Then

(12)

and crosstalk Xtk = 0.0012 or 58dB.

If Rgbk is changed to 10 or Zhs is changed to 16, crosstalk becomes Xtk = 0.0019, or 54dB.

These are low figures, but they would cause failure with specifications like the one for Microsoft Vista.

This is less likely to occur with fully integrated devices, in which resistor match is much better than 1%.These devices generally have very high common-mode rejection. Common-mode rejection is the ratio ofthe output relative to ground divided by common-mode input, ( Vo.C / Vi.C ), as defined in (A) below. Gainerror, the difference between input and output divided by input, is defined in (B) below.

Except for a sign reversal, relative voltages from the input nodes to the output nodes are the same, so

gain error equals CMR as defined in this figure. In other words,

= CMR. In fully integrated devices likemembers of the TPA613x family, CMR is typically 60dB (0.1%) and lower. The calculation above inwhich gain error was assumed to be 1% can be updated with this new figure.

Then, with = 0.1%, Rgbk = 5 and Zhs = 32, crosstalk Xtk = 0.00012 or 78dB.

If Rgbk is changed to 10 or Zhs is changed to 16, crosstalk becomes Xtk = 0.00019, or 74dB.

These figures easily comply with specifications like the one for Microsoft Vista.




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( )Zhs

Vglb = Vo Zhs + 2Rgbk

2VoPo =

Zhs

22

2

ZhsVo

(Zhs + 2Pgbk)VglbPglb == =

Zhs Zhs

2Pglb Zhs

=Po (Zhs + 2Rgbk)

.( )

232

0 5832 2 5

=

+

www.ti.com Potential Power Loss in GLB Headphone Amplifier

8 Potential Power Loss in GLB Headphone Amplifier

The ground break resistor Rgbk in series with headphone loads reduces maximum available load power.This is an advantage if it helps limit output power as required to meet various safety specifications. If itreduces power below the levels in those specifications, it can be a disadvantage.

This analysis will assume that maximum output voltage from the GLB amplifiers is fixed. This is often not

the case, for a couple of reasons. Voltage saturation drops in output devices depend on load currents.Also, many of these amplifiers use dual power supplies with a negative supply generated from a positivesystem supply. Usually the negative supply is produced by a charge pump with relatively high outputimpedance. In these cases increasing load impedance can increase maximum output voltage from theamplifiers, but this is difficult to predict and factor into an analysis.

With fixed output voltage, loss in output power can be analyzed as follows, using Vo as the maximumoutput voltage from the GLB amplifiers and Vhs as the net voltage across headset loads. It is assumedthat left and right output voltages are essentially identical. This is the worst case for output power loss.

Output voltage with Rgbk is

(13)

Output power without Rgbk is

(14)

Output power with Rgbk is

(15)

Power with Rgbk relative to power without Rgbk is

(16)

For Rgbk = 5 and Zhs = 32, this is a factor of

(17)

For Rgbk = 5 and Zhs = 16, the factor becomes 0.38.

By themselves, these factors do not provide clear meaning, but they can be translated to output power byassuming some initial output power per channel and computing power with Rgbk added.

For Rgbk = 5, Zhs = 32 and initial power = 50mW, power with Rgbk = 0.58 50 = 29mW.

For Rgbk = 5, Zhs = 16 and initial power = 100mW, power with Rgbk = 0.38 100 = 38mW.

Note that output power is more nearly the same with the different load impedances with Rgbk added.Power with Zhs = 16 is only about 1/3 higher than with 32, rather than twice as high. So Rgbk enablesGLB operation, and it also limits power output and provides more constant output power versus load

impedance. In many cases these results can be advantages.Devices like TPA6132A2 limit output power and make it relatively constant versus load impedance topermit complying with new safety regulations regarding potential for hearing damage. These devices userelatively low voltage power supplies and finite power supply output impedance to produce this result.Lower supply voltage provides power limiting, and finite impedance equalizes output versus load.TPA6132A2 limits output power to 22mW with 32 loads and 25mW with 16 loads at 1% THD+N byusing positive and negative 1.8V supply rails with output impedance of about 8. Adding a ground loopbreak resistor will reduce output power, but not as dramatically as in the example above.


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2Zhs

(Zhs + 2 Rgbk)

( )( )

2

2

2

Zhs

(Zhs+2(Zps+Rgbk))Pglb Zhs+2Zps= =

Po Zhs+2 Zps+RgbkZhs

Zhs+2Zps

( )( )( )

2

32 2 80.68

32 2 8 5

+ = + +

( )( )( )

2

16 2 80.58

16 2 8 5

+ = + +

Potential Power Loss in GLB Headphone Amplifier www.ti.com

It is easy to predict the result by recognizing that power supply output impedance Zps is in series with theheadphone load, just like Rgbk, so it will have the same effect in reducing maximum output power.Relative output power without and with Rgbk can be calculated as the ratio of the result above,

(18)

with Rgbk replaced with (Zps+Rgbk), to that result with Rgbk replaced with Zps.

Power with Zps and Rgbk relative to power with only Zps can be calculated to be

(19)

For Zps = 8, Rgbk = 5 and Zhs = 32, this is a factor of

(20)

Resulting output power with 32 headphones is about 15mW per channel.

For Zps = 8, Rgbk = 5 and Zhs = 16, this is a factor of

(21)

Resulting output power with 16 headphones is again about 15mW per channel.




9/14

AUDIO

SOURCE

Rgbk

GLBLINEor

HEADPHONE

OUTPUT

+

-

+

-

2 INL+

1 INL

3 INR+

4 INR

OUTR5

OUTL 16

SGND

15

10PGND

TPA6132A2

5

1F10V

1F10V

1F10V

1F10V

www.ti.com Appendix A

Appendix A GLB OUTPUT CIRCUIT IMPLEMENTED WITH TPA6132A2

The following schematic illustrates a GLB output for driving line inputs or headphones implemented withTPA6132A2. The circuit uses a low value GLB resistor, Rgbk, typically 5 to 20 ohms, plus the 2 differentialheadphone amplifiers in TPA6132A2. SGND is the ground reference of TPA6132A2 differential amplifier

inputs. Power supply, charge pump and logic pins and circuits are omitted for simplicity (refer to the datasheet and EVM users guide for these). Gain of the differential amplifiers is set as required for eachspecific application.

TPA6132A2 and other devices with SGND in the TPA613x family are well suited for this applicationbecause they provide a small, highly integrated solution with high-CMRR differential amplifiers. Since thedifferential amplifiers are completely integrated into the device, there are no resistors except Rgbk to addto TPA6132A2 to complete a GLB output, and the inherent high CMRR of the differential amplifiersprevents crosstalk problems.

9SLOA143 October 2009



10/14

AUDIO

SOURCE

Rgbk

GLBLINEor

HEADPHONE

OUTPUT

-

+

-

+

Ri

Ri

Rf

Rf

Ri

Ri

Rf

Rf

AUDIO

SOURCE

Rgbk

GLBLINEor

HEADPHONE

OUTPUT

-

+

-

+

Ri

Ri

Rf

Rf

Ri

Ri

Rf

Rf

TPA

6132A2

5

Appendix B www.ti.com

Appendix B GLB CIRCUIT IMPLEMENTATIONS

B.1 GLB Output Circuit Implementations

The following schematic illustrates a GLB output for driving line inputs or headphones. The circuit uses a

low value GLB resistor, Rgbk, plus standard single-opamp differential amplifiers. Ri and Rf set circuit gainto (Rf/Ri), and Rgbk is typically 5 to 20. The circuit as drawn inverts phase, but the inputs may bereversed at the audio sources if this is a problem.

TI devices like TPA6132A2, DRV602, DRV603, DRV604 make good candidates for use in GLB outputcircuits.

In many cases it is not necessary or possible to use separate resistor chains at the non-inverting inputs ofthe opamps, and they are combined into one chain. In this case the circuit must invert the input signal,because the opamp feedback chains must be distinct. Circuit gain is (Rf/Ri). The resistors in the combined

chain, Rh and Re, must have the same ratio as Ri and Rf, but their values do not have to be the same.This is because common-mode voltage rejection of this form of differential amplifier depends on ratios andnot absolute resistor values.

10 SLOA143 October 2009



11/14

AUDIO

SOURCE

Rgbk

GLBLINEor

HEADPHONE

OUTPUT

-

+

+

-

Ri Rf

R h

R i

R e

R f

AUDIO

RECEIVER

Rgbk

GLBLINE

INPUT

-

+

-

+

Ri

Ri

Rf

Rf

Rs

Rs

Rx

Rx

www.ti.com GLB Input Circuit Implementations

TI devices like TPA4411, DRV600, DRV601 make good candidates for use in these circuits.

A side note: a GLB output may be implemented with an audio subsystem, codec or other device with anavailable mono input that can be summed to its outputs. It is simply necessary to connect this input to thejunction of Rgbk and the HP jack sleeve and set its gain to the outputs to 1.

B.2 GLB Input Circuit Implementations

The following schematic illustrates a GLB line input. As before, the circuit uses a low value GLB resistor,Rgbk, plus standard single-opamp differential amplifiers. Ri and Rf set circuit gain to (Rf/Ri), and Rgbk istypically 5 to 20. The circuit as drawn inverts phase, but the inputs may be reversed at the audio inputs ifthis is a problem.

As before, in many cases it is not necessary or possible to use separate resistor chains at thenon-inverting inputs of the opamps, and they are combined into one chain. In this case the circuit mustinvert the input signal, because the opamp feedback chains must be distinct. Circuit gain is (Rf/Ri). Again,the resistors in the combined chain, Rh and Re, must have the same ratio as Ri and Rf, but their valuesdo not have to be the same.


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12/14

AUDIO

RECEIVER

Rgbk

GLBLINE

INPUT

-

+

Ri

R h

Rf

R e

R i R f

+

-

GLB Input Circuit Implementations www.ti.com

Again, a GLB input may be implemented with an audio subsystem, codec or other device with an availablemono input that can be summed to its outputs. It is simply necessary to connect this input to the junctionof Rgbk and the input jack sleeve and set its gain to the outputs to 1 times channel gain.




13/14

AUDIOSOURCE

Gs

AUDIOCABLE

AUDIO RECEIVER

Gr(Gs Gr)

Operating

currents

Operating

currents

Decoupling

currents

Zs

Decoupling

currents

Zr

POWER

SUPPLY

WITH

NOISE

www.ti.com Appendix C

Appendix C HOW GROUND LOOP INTERFERENCE OCCURS

Grounded audio components generally carry significant currents in their ground returns. These currentsare produced by power supply ripple and component operation. They create potentials between the localgrounds of the audio components and system ground that add interference in audio signal connections

between components. This is illustrated in the drawing below.

The power source to the system components may be AC mains or a vehicle battery. In either case, thereare 2 ways for a ground connection to produce potentials at the local grounds of components. Powersource AC voltage or ripple drives currents through decoupling and other circuits of a component into itsground wire, and operating currents produced by the component are returned through the ground wire aswell. All ground returns have finite impedance, so these currents create a potential along the ground wire.These currents and impedances differ from component to component, so ground potentials differ from

component to component as well. We consider a ground loop to be a connection between 2 of thesepotentials.

13SLOA143 October 2009



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I M P O R T A N T N O T I C E

T e x a s I n s t r u m e n t s I n c o r p o r a t e d a n d i t s s u b s i d i a r i e s ( T I ) r e s e r v e t h e r i g h t t o m a k e c o r r e c t i o n s , m o d i f i c a t i o n s , e n h a n c e m e n t s , i m p r o v e m e n t s , a n d o t h e r c h a n g e s t o i t s p r o d u c t s a n d s e r v i c e s a t a n y t i m e a n d t o d i s c o n t i n u e a n y p r o d u c t o r s e r v i c e w i t h o u t n o t i c e . C u s t o m e r s s h o u l do b t a i n t h e l a t e s t r e l e v a n t i n f o r m a t i o n b e f o r e p l a c i n g o r d e r s a n d s h o u l d v e r i f y t h a t s u c h i n f o r m a t i o n i s c u r r e n t a n d c o m p l e t e . A l l p r o d u c t s a r e s o l d s u b j e c t t o T I s t e r m s a n d c o n d i t i o n s o f s a l e s u p p l i e d a t t h e t i m e o f o r d e r a c k n o w l e d g m e n t .

T I w a r r a n t s p e r f o r m a n c e o f i t s h a r d w a r e p r o d u c t s t o t h e s p e c i f i c a t i o n s a p p l i c a b l e a t t h e t i m e o f s a l e i n a c c o r d a n c e w i t h T I s s t a n d a r d

w a r r a n t y . T e s t i n g a n d o t h e r q u a l i t y c o n t r o l t e c h n i q u e s a r e u s e d t o t h e e x t e n t T I d e e m s n e c e s s a r y t o s u p p o r t t h i s w a r r a n t y . E x c e p t w h e r e m a n d a t e d b y g o v e r n m e n t r e q u i r e m e n t s , t e s t i n g o f a l l p a r a m e t e r s o f e a c h p r o d u c t i s n o t n e c e s s a r i l y p e r f o r m e d .

T I a s s u m e s n o l i a b i l i t y f o r a p p l i c a t i o n s a s s i s t a n c e o r c u s t o m e r p r o d u c t d e s i g n . C u s t o m e r s a r e r e s p o n s i b l e f o r t h e i r p r o d u c t s a n d a p p l i c a t i o n s u s i n g T I c o m p o n e n t s . T o m i n i m i z e t h e r i s k s a s s o c i a t e d w i t h c u s t o m e r p r o d u c t s a n d a p p l i c a t i o n s , c u s t o m e r s s h o u l d p r o v i d e a d e q u a t e d e s i g n a n d o p e r a t i n g s a f e g u a r d s .

T I d o e s n o t w a r r a n t o r r e p r e s e n t t h a t a n y l i c e n s e , e i t h e r e x p r e s s o r i m p l i e d , i s g r a n t e d u n d e r a n y T I p a t e n t r i g h t , c o p y r i g h t , m a s k w o r k r i g h t , o r o t h e r T I i n t e l l e c t u a l p r o p e r t y r i g h t r e l a t i n g t o a n y c o m b i n a t i o n , m a c h i n e , o r p r o c e s s i n w h i c h T I p r o d u c t s o r s e r v i c e s a r e u s e d . I n f o r m a t i o np u b l i s h e d b y T I r e g a r d i n g t h i r d - p a r t y p r o d u c t s o r s e r v i c e s d o e s n o t c o n s t i t u t e a l i c e n s e f r o m T I t o u s e s u c h p r o d u c t s o r s e r v i c e s o r a w a r r a n t y o r e n d o r s e m e n t t h e r e o f . U s e o f s u c h i n f o r m a t i o n m a y r e q u i r e a l i c e n s e f r o m a t h i r d p a r t y u n d e r t h e p a t e n t s o r o t h e r i n t e l l e c t u a l p r o p e r t y o f t h e t h i r d p a r t y , o r a l i c e n s e f r o m T I u n d e r t h e p a t e n t s o r o t h e r i n t e l l e c t u a l p r o p e r t y o f T I .

R e p r o d u c t i o n o f T I i n f o r m a t i o n i n T I d a t a b o o k s o r d a t a s h e e t s i s p e r m i s s i b l e o n l y i f r e p r o d u c t i o n i s w i t h o u t a l t e r a t i o n a n d i s a c c o m p a n i e d b y a l l a s s o c i a t e d w a r r a n t i e s , c o n d i t i o n s , l i m i t a t i o n s , a n d n o t i c e s . R e p r o d u c t i o n o f t h i s i n f o r m a t i o n w i t h a l t e r a t i o n i s a n u n f a i r a n d d e c e p t i v e b u s i n e s s p r a c t i c e . T I i s n o t r e s p o n s i b l e o r l i a b l e f o r s u c h a l t e r e d d o c u m e n t a t i o n . I n f o r m a t i o n o f t h i r d p a r t i e s m a y b e s u b j e c t t o a d d i t i o n a l r e s t r i c t i o n s .

R e s a l e o f T I p r o d u c t s o r s e r v i c e s w i t h s t a t e m e n t s d i f f e r e n t f r o m o r b e y o n d t h e p a r a m e t e r s s t a t e d b y T I f o r t h a t p r o d u c t o r s e r v i c e v o i d s a l l

e x p r e s s a n d a n y i m p l i e d w a r r a n t i e s f o r t h e a s s o c i a t e d T I p r o d u c t o r s e r v i c e a n d i s a n u n f a i r a n d d e c e p t i v e b u s i n e s s p r a c t i c e . T I i s n o t r e s p o n s i b l e o r l i a b l e f o r a n y s u c h s t a t e m e n t s .

T I p r o d u c t s a r e n o t a u t h o r i z e d f o r u s e i n s a f e t y - c r i t i c a l a p p l i c a t i o n s ( s u c h a s l i f e s u p p o r t ) w h e r e a f a i l u r e o f t h e T I p r o d u c t w o u l d r e a s o n a b l y b e e x p e c t e d t o c a u s e s e v e r e p e r s o n a l i n j u r y o r d e a t h , u n l e s s o f f i c e r s o f t h e p a r t i e s h a v e e x e c u t e d a n a g r e e m e n t s p e c i f i c a l l y g o v e r n i n g s u c h u s e . B u y e r s r e p r e s e n t t h a t t h e y h a v e a l l n e c e s s a r y e x p e r t i s e i n t h e s a f e t y a n d r e g u l a t o r y r a m i f i c a t i o n s o f t h e i r a p p l i c a t i o n s , a n d a c k n o w l e d g e a n d a g r e e t h a t t h e y a r e s o l e l y r e s p o n s i b l e f o r a l l l e g a l , r e g u l a t o r y a n d s a f e t y - r e l a t e d r e q u i r e m e n t s c o n c e r n i n g t h e i r p r o d u c t s a n d a n y u s e o f T I p r o d u c t s i n s u c h s a f e t y - c r i t i c a l a p p l i c a t i o n s , n o t w i t h s t a n d i n g a n y a p p l i c a t i o n s - r e l a t e d i n f o r m a t i o n o r s u p p o r t t h a t m a y b e p r o v i d e d b y T I . F u r t h e r , B u y e r s m u s t f u l l y i n d e m n i f y T I a n d i t s r e p r e s e n t a t i v e s a g a i n s t a n y d a m a g e s a r i s i n g o u t o f t h e u s e o f T I p r o d u c t s i n s u c h s a f e t y - c r i t i c a l a p p l i c a t i o n s .

T I p r o d u c t s a r e n e i t h e r d e s i g n e d n o r i n t e n d e d f o r u s e i n m i l i t a r y / a e r o s p a c e a p p l i c a t i o n s o r e n v i r o n m e n t s u n l e s s t h e T I p r o d u c t s a r e s p e c i f i c a l l y d e s i g n a t e d b y T I a s m i l i t a r y - g r a d e o r " e n h a n c e d p l a s t i c . " O n l y p r o d u c t s d e s i g n a t e d b y T I a s m i l i t a r y - g r a d e m e e t m i l i t a r y s p e c i f i c a t i o n s . B u y e r s a c k n o w l e d g e a n d a g r e e t h a t a n y s u c h u s e o f T I p r o d u c t s w h i c h T I h a s n o t d e s i g n a t e d a s m i l i t a r y - g r a d e i s s o l e l y a t t h e B u y e r ' s r i s k , a n d t h a t t h e y a r e s o l e l y r e s p o n s i b l e f o r c o m p l i a n c e w i t h a l l l e g a l a n d r e g u l a t o r y r e q u i r e m e n t s i n c o n n e c t i o n w i t h s u c h u s e .

T I p r o d u c t s a r e n e i t h e r d e s i g n e d n o r i n t e n d e d f o r u s e i n a u t o m o t i v e a p p l i c a t i o n s o r e n v i r o n m e n t s u n l e s s t h e s p e c i f i c T I p r o d u c t s a r e d e s i g n a t e d b y T I a s c o m p l i a n t w i t h I S O / T S 1 6 9 4 9 r e q u i r e m e n t s . B u y e r s a c k n o w l e d g e a n d a g r e e t h a t , i f t h e y u s e a n y n o n - d e s i g n a t e d p r o d u c t s i n a u t o m o t i v e a p p l i c a t i o n s , T I w i l l n o t b e r e s p o n s i b l e f o r a n y f a i l u r e t o m e e t s u c h r e q u i r e m e n t s .

F o l l o w i n g a r e U R L s w h e r e y o u c a n o b t a i n i n f o r m a t i o n o n o t h e r T e x a s I n s t r u m e n t s p r o d u c t s a n d a p p l i c a t i o n s o l u t i o n s :

P r o d u c t s A p p l i c a t i o n s A m p l i f i e r s a m p l i f i e r . t i . c o m A u d i o w w w . t i . c o m / a u d i o D a t a C o n v e r t e r s d a t a c o n v e r t e r . t i . c o m A u t o m o t i v e w w w . t i . c o m / a u t o m o t i v e D L P P r o d u c t s w w w . d l p . c o m B r o a d b a n d w w w . t i . c o m / b r o a d b a n d D S P d s p . t i . c o m D i g i t a l C o n t r o l w w w . t i . c o m / d i g i t a l c o n t r o l C l o c k s a n d T i m e r s w w w . t i . c o m / c l o c k s M e d i c a l w w w . t i . c o m / m e d i c a l I n t e r f a c e i n t e r f a c e . t i . c o m M i l i t a r y w w w . t i . c o m / m i l i t a r y L o g i c l o g i c . t i . c o m O p t i c a l N e t w o r k i n g w w w . t i . c o m / o p t i c a l n e t w o r k P o w e r M g m t p o w e r . t i . c o m S e c u r i t y w w w . t i . c o m / s e c u r i t y M i c r o c o n t r o l l e r s m i c r o c o n t r o l l e r . t i . c o m T e l e p h o n y w w w . t i . c o m / t e l e p h o n y R F I D w w w . t i - r f i d . c o m V i d e o & I m a g i n g w w w . t i . c o m / v i d e o R F / I F a n d Z i g B e e S o l u t i o n s w w w . t i . c o m / l p r f W i r e l e s s w w w . t i . c o m / w i r e l e s s

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