TEXAS INSTRUMENTS XTR1064 Technical data

XTR106

BRIDGE NONLINEARITY CORRECTION

USING XTR106

0

Bridge Output (mV)

10

2.0

1.5

1.0

0.5

0

–0.5

Uncorrected
Bridge Output

Corrected

5

Nonlinearity (%)

X

TR

1

06

SBOS092A – JUNE 1998 – REVISED NOVEMBER 2003

4-20mA CURRENT TRANSMITTER

with Bridge Excitation and Linearization

XTR106

FEATURES

● LOW TOTAL UNADJUSTED ERROR

● 2.5V, 5V BRIDGE EXCITATION REFERENCE

● 5.1V REGULATOR OUTPUT

● LOW SPAN DRIFT: ±25ppm/°C max

● LOW OFFSET DRIFT: 0.25µV/°C

● HIGH PSR: 110dB min

● HIGH CMR: 86dB min

● WIDE SUPPLY RANGE: 7.5V to 36V

● 14-PIN DIP AND SO-14 SURFACE-MOUNT

DESCRIPTION

The XTR106 is a low cost, monolithic 4-20mA, two­wire current transmitter designed for bridge sensors. It
provides complete bridge excitation (2.5V or 5V refer­ence), instrumentation amplifier, sensor linearization,
and current output circuitry. Current for powering ad­ditional external input circuitry is available from the
V

pin.

REG

The instrumentation amplifier can be used over a wide
range of gain, accommodating a variety of input signal
types and sensors. Total unadjusted error of the com­plete current transmitter, including the linearized bridge,
is low enough to permit use without adjustment in many
applications. The XTR106 operates on loop power sup­ply voltages down to 7.5V.

Linearization circuitry provides second-order correction
to the transfer function by controlling bridge excitation
voltage. It provides up to a 20:1 improvement in
nonlinearity, even with low cost transducers.

The XTR106 is available in 14-pin plastic DIP and
SO-14 surface-mount packages and is specified for the
–40°C to +85°C temperature range. Operation is from
–55°C to +125°C.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.

APPLICATIONS

● PRESSURE BRIDGE TRANSMITTERS

● STRAIN GAGE TRANSMITTERS

● TEMPERATURE BRIDGE TRANSMITTERS

● INDUSTRIAL PROCESS CONTROL

● SCADA REMOTE DATA ACQUISITION

● REMOTE TRANSDUCERS

● WEIGHING SYSTEMS

● ACCELEROMETERS

5V

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V

(5.1V)

REG

2.5V

V

V

REF

REF

5

R

Lin

Polarity

LIN

7.5V to 36V

I

OUT

4-20mA

+

I

G

RET

XTR106

–

R

Copyright © 1998-2003, Texas Instruments Incorporated

V

PS

V

O

R

L

SPECIFICATIONS

At TA = +25°C, V+ = 24V, and TIP29C external transistor, unless otherwise noted.

XTR106P, U XTR106PA, UA
PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
OUTPUT

Output Current Equation I
Output Current, Specified Range 4 20 ✻✻mA
Over-Scale Limit I
Under-Scale Limit I

ZERO OUTPUT

(1)

Initial Error ±5 ±25 ✻ ±50 µA

vs Temperature T
vs Supply Voltage, V+ V+ = 7.5V to 36V 0.04 0.2 ✻✻ µA/V
vs Common-Mode Voltage
vs V

(IO) 0.8 ✻ µA/mA

REG

Noise: 0.1Hz to 10Hz i

(CMRR)

OVER

UNDER

I

ZERO

O

I

= 0, I

REG

I

+ I

REF

= 0 1 1.6 2.2 ✻✻✻ mA

REF

= 2.5mA 2.9 3.4 4 ✻✻✻ mA

REG

VIN = 0V, RG = ∞ 4 ✻ mA

= –40°C to +85°C ±0.07 ±0.9 ✻✻ µA/°C

A

VCM = 1.1V to 3.5V

n

(5)

SPAN

Span Equation (Transconductance) S
Untrimmed Error Full Scale (V
vs Temperature
Nonlinearity: Ideal Input

INPUT

Offset Voltage V

vs Temperature T
vs Supply Voltage, V+ V+ = 7.5V to 36V ±0.1 ±3 ✻✻ µV/V

vs Common-Mode Voltage, RTI CMRR V
Common-Mode Range
Input Bias Current I

vs Temperature T
Input Offset Current I

vs Temperature T
Impedance: Differential Z

Noise: 0.1Hz to 10Hz V

VOLTAGE REFERENCES

(2)

(3)

(4)

(5)

Common-Mode 5 || 10 ✻ GΩ || pF

(5)

TA = –40°C to +85°C ±3 ±25 ✻✻ ppm/°C

Full Scale (VIN) = 50mV ±0.001 ±0.01 ✻✻ %

OS

V

CM

OS

IN

= –40°C to +85°C ±0.25 ±1.5 ✻ ±3 µV/°C

A

CM

B

= –40°C to +85°C20 ✻ pA/°C

A

= –40°C to +85°C5 ✻ pA/°C

A

n

Lin Polarity Connected

to V

Initial: 2.5V Reference V

5V Reference V

Accuracy V

vs Temperature T

vs Supply Voltage, V+ V+ = 7.5V to 36V ±5 ±20 ✻✻ ppm/V

vs Load I
Noise: 0.1Hz to 10Hz 10 ✻ µVp-p

(5)

V

REG

Accuracy ±0.02 ±0.1 ✻✻ V

vs Temperature T

vs Supply Voltage, V+ V+ = 7.5V to 36V 1 ✻ mV/V
Output Current I
Output Impedance I

LINEARIZATION

R

(external) Equation R

LIN

K

Linearization Factor K

LIN

(6)

2.5 2.5 ✻ V

REF

55✻ V

V

REF

REG

REG

LIN

LIN

REF

= –40°C to +85°C ±20 ±35 ✻ ±75 ppm/°C

A

REF

= –40°C to +85°C ±0.3 ✻ mV/°C

A

REG

Accuracy ±1 ±5 ✻✻ %

vs Temperature T
Max Correctable Sensor Nonlinearity B V

= –40°C to +85°C ±50 ±100 ✻✻ ppm/°C

A

) = 50mV ±0.05 ±0.2 ✻ ±0.4 %

IN

VCM = 2.5V ±50 ±100 ✻ ±250 µV

= 1.1V to 3.5V

, R

REG

(5)

= 0

LIN

= 2.5V or 5V ±0.05 ±0.25 ✻ ±0.5 %

= 0mA to 2.5mA 60 ✻ ppm/mA

= 0mA to 2.5mA 80 ✻ Ω

V

= 5V 6.645 ✻ kΩ

REF

V

= 2.5V 9.905 ✻ kΩ

REF

= 5V ±5 ✻ % of V

REF

V

= 2.5V –2.5, +5 ✻ % of V

REF

POWER SUPPLY V+
Specified +24 ✻ V
Voltage Range +7.5 +36 ✻✻V

TEMPERATURE RANGE

Specification –40 +85 ✻✻°C
Operating –55 +125 ✻✻°C
Storage –55 +125 ✻✻°C
Thermal Resistance

14-Pin DIP 80 ✻ °C/W

θ

JA

SO-14 Surface Mount 100 ✻ °C/W

✻ Specification same as XTR106P, XTR106U.
NOTES: (1) Describes accuracy of the 4mA low-scale offset current. Does not include input amplifier effects. Can be trimmed to zero. (2) Does not include initial

error or TCR of gain-setting resistor, R
measured with respect to I

pin. (6) See “Linearization” text for detailed explanation. VFS = full-scale VIN.

RET

. (3) Increasing the full-scale input range improves nonlinearity. (4) Does not include Zero Output initial error. (5) Voltage

G

IO = VIN • (40/RG) + 4mA, VIN in Volts, RG in Ω

24 28 30 ✻✻✻ mA

0.02 ✻ µA/V

0.035 ✻ µAp-p

S = 40/R

G

✻ A/V

±10 ±50 ✻ ±100 µV/V

1.1 3.5 ✻✻V
525 ✻ 50 nA

±0.2 ±3 ✻ ±10 nA

0.1 || 1 ✻ GΩ || pF

0.6 ✻ µVp-p

5.1 ✻ V

See Typical Curves ✻ mA

R

= K

LIN

4B

• , K

LIN

1 – 2B

in Ω, B is nonlinearity relative to V

LIN

FS

A

Ω

FS
FS

2

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XTR106

SBOS092A

PIN CONFIGURATION

Top View DIP and SOIC

1

V

REG

–

2

V

IN

3

R

G

4

R

G

+

5

V

IN

6

I

RET

7

I

O

14
13
12
11
10

9
8

V

5

REF

V

2.5

REF

Lin Polarity
R

LIN

V+
B (Base)
E (Emitter)

PACKAGE/ORDERING INFORMATION

For the most current package and ordering information, see
the Package Option Addendum at the end of this data sheet.

ABSOLUTE MAXIMUM RATINGS

Power Supply, V+ (referenced to IO pin).......................................... 40V

Input Voltage, V

Storage Temperature Range ....................................... –55°C to +125°C

Lead Temperature (soldering, 10s) .............................................. +300°C

Output Current Limit ............................................................... Continuous

Junction Temperature ................................................................... +165°C

NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may degrade
device reliability.

+

–

, VIN (referenced to I

IN

(1)

pin) ......................... 0V to V+

RET

ELECTROSTATIC
DISCHARGE SENSITIVITY

This integrated circuit can be damaged by ESD. Texas Instru­ments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.

ESD damage can range from subtle performance degrada­tion to complete device failure. Precision integrated circuits
may be more susceptible to damage because very small
parametric changes could cause the device not to meet its
published specifications.

XTR106

SBOS092A

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3

FUNCTIONAL DIAGRAM

Lin

Polarity

V

REG

12

R

LIN

11

1

V+

10

14

V

5

REF

REF

13

2.5

5

+

V

IN

V

4

REF

Amp

Bandgap

V

REF

100µA

Lin

Amp

Current

Direction

Switch

5.1V

B
9

R

G

975

3

V

2

–

V

IN

I = 100µA +

IN

R

G

25

Ω

Ω

E
8

6

I

RET

4

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7

= 4mA + V

I

O

• ( )

IN

40

R

G

XTR106

SBOS092A

TYPICAL PERFORMANCE CURVES

At TA = +25°C, V+ = 24V, unless otherwise noted.

60

RG = 50Ω

50

40

30

RG = 1kΩ

C

C

OUT

C

OUT

connected

C

OUT

between V+ and I

20

TRANSCONDUCTANCE vs FREQUENCY

10

Transconductance (20 log mA/V)

= 250Ω

R

L

0

100 1k 10k 100k 1M

Frequency (Hz)

COMMON-MODE REJECTION vs FREQUENCY

110
100

90
80
70

RG = 1kΩ

RG = 50Ω

60
50

Common-Mode Rejection (dB)

40
30

10 1k100 10k 100k 1M

Frequency (Hz)

= 0.01µF

= 0.01µF

OUT

= 0.033µF

STEP RESPONSE

C

= 0.01µF

RG = 1kΩ

O

20mA

OUT

RG = 50Ω

4mA/div

4mA

50µs/div

POWER SUPPLY REJECTION vs FREQUENCY

160
140

RG = 50Ω

C

= 0

OUT

120

= 1kΩ

R

G

100

80
60
40

Power Supply Rejection (dB)

20

0

10 1k100 10k 100k 1M

Frequency (Hz)

90
80
70
60
50
40
30

Percent of Units (%)

20
10

0

XTR106

SBOS092A

INPUT OFFSET VOLTAGE DRIFT

PRODUCTION DISTRIBUTION

Typical production
distribution of
packaged units.

1.5

1.0

0.5

INPUT OFFSET VOLTAGE CHANGE

and V

vs V

REG

VOS vs I

CURRENTS

REF

REG

0

(µV)

–0.5

OS

∆ V

–1.0

VOS vs I

REF

–1.5
–2.0
–2.5

0

0.25

0.5

0.75

1.0

1.25

1.5

1.75

2.0

2.25

2.5

2.75

3.0

–1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5

Current (mA)

Offset Voltage Drift (µV/°C)

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5

TYPICAL PERFORMANCE CURVES (CONT)

At TA = +25°C, V+ = 24V, unless otherwise noted.

2.5

UNDER-SCALE CURRENT vs TEMPERATURE

2.0

1.5

1.0

Under-Scale Current (mA)

0.5
V+ = 7.5V to 36V

0

–75 –50 –25 0 25 50 75 100

Temperature (°C)

OVER-SCALE CURRENT vs TEMPERATURE

30

With External Transistor

29

28

V+ = 36V

27

26

Over-Scale Current (mA)

25

V+ = 24V

V+ = 7.5V

24

–75 –50 –25 0 25 50 75 100

Temperature (°C)

125

125

4.0

UNDER-SCALE CURRENT vs I

REF

3.5
T

3.0

= –55°C

A

2.5

2.0

TA = +25°C

1.5

1.0

Under-Scale Current (mA)

TA = +125°C

0.5

0

0 0.5 1.0 1.5 2.0 2.5

+ I

REG

(mA)

I

REF

ZERO OUTPUT ERROR

3.0

vs V

REF

and V

CURRENTS

REG

2.5

2.0

I

ZERO

Error vs I

1.5

1.0

0.5

0

Zero Output Error (µA)

I

ZERO

Error vs I

–0.5
–1.0

–1 –0.5 0 0.5 1.0 1.5 2.0

Current (mA)

+ I

REG

REG

REF

2.5

ZERO OUTPUT CURRENT ERROR

4
2
0

–2
–4
–6
–8

Zero Output Current Error (µA)

–10
–12

–75 –50 –25 0 25 50 75 100

6

vs TEMPERATURE

Temperature (°C)

125

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70

60

50

40

30

20

Percent of Units (%)

10

0

0

0.1

0.05

0.15

ZERO OUTPUT DRIFT

PRODUCTION DISTRIBUTION

Typical production
distribution of
packaged units.

0.2

0.3

0.4

0.5

0.25

0.35

0.45

0.55

0.6

Zero Output Drift (µA/°C)

0.65

0.7

0.8

0.85

0.9

0.75

XTR106

SBOS092A

TYPICAL PERFORMANCE CURVES (CONT)

10 100 1k 10k 100k 1M

Frequency (Hz)

REFERENCE AC LINE REJECTION vs FREQUENCY

120

100

80

60

40

20

0

Line Rejection (dB)

V

REF

2.5

V

REF

5

At TA = +25°C, V+ = 24V, unless otherwise noted.

INPUT VOLTAGE, INPUT CURRENT, and ZERO

OUTPUT CURRENT NOISE DENSITY vs FREQUENCY

10k

Zero Output Noise

1k

Input Current Noise

100

Input Voltage Noise (nV/√Hz)

10

Input Voltage Noise

1 10 100 1k 10k

Frequency (Hz)

V

5.6

OUTPUT VOLTAGE vs V

REG

OUTPUT CURRENT

REG

5.5

5.4

5.3

5.2

5.1

Output Current (V)

REG

5.0

V

4.9

TA = +125°C

TA = +25°C, –55°C

4.8
–1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5

Output Current (mA)

V

REG

100k

10k

1k

100

10

Input Current Noise (fA/√Hz)

Zero Output Current Noise (pA/√Hz)

INPUT BIAS and OFFSET CURRENT

vs TEMPERATURE

10

8

6

I

B

4

2

I

0

OS

Input Bias and Offset Current (nA)

–2

–75 –50 –25 0 25 50 75 100 125

Temperature (°C)

REFERENCE TRANSIENT RESPONSE

= 5V

V

REF

50mV/div

500µA/div

10µs/div

Output

Reference

1mA

0

5 vs V

V

REF

5.008

5.004

5.000

5 (V)

REF

V

4.996

4.992

4.988
–1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5

V

REG

XTR106

SBOS092A

OUTPUT CURRENT

REG

T

= +25°C

A

T

= +125°C

A

T

= –55°C

A

Current (mA)

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