XTR108EA-2K5 BURR-BROWN [Burr-Brown Corporation], XTR108EA-2K5 Datasheet - Page 21

• Manufacturer Part Number: XTR108EA-2K5
• Manufacturer: BURR-BROWN [Burr-Brown Corporation]

TABLE XVII. Sample Error Budget Calculation.
SAMPLE ERROR ANALYSIS
Table XVII shows a detailed computation of the error
accumulation. The sample error budget is based on a typical
RTD circuit (Pt100, 200 C measurement span). Note that
these calculations are based on typical characteristics where
no maximum or minimum characteristic is available. The
XTR108
SAMPLE ERROR CALCULATION
RTD value at 4mA Output (R
Mode Voltage Change ( CM) 0.1V.
Chosen XTR108 parameters: PGIA gain = 50; I
SBOS187C
NOTES: (1) Does not contribute to the output error due to calibration. (2) All errors are referred to input unless otherwise stated. (3) Calculated as root-
sum–square.
ERROR SOURCE
INPUT
Input Offset Voltage
Input Bias Current
Input Offset Current
EXCITATION
Current Reference Accuracy
Current Reference Matching
DAC Resolution and Linearity
GAIN
Span
Nonlinearity
OUTPUT
Zero Output
DAC Resolution and Linearity
DRIFT ( T
Input Offset Voltage
Current Reference Accuracy
Current Reference Matching
Span
Zero Output
NOISE (0.1Hz to 10Hz, Typ)
Input Offset Voltage
Current Reference
Zero Output
vs Common Mode
vs Common Mode
vs Supply
A
= 20 C)
RTD MIN
) 100 : RTD Measurement Range 200 C; Ambient Temperature Range ( T
Drift • T
I
1LSB
REF
CM/R
(I
REF
CMRR • CM/(V
Nonlinearity (%)/100% • 10
ZERO
Noise • R
Drift • T
FINE
I
= 518.9 A; Full-scale V
ZERO
OUT
2LSB
ERROR EQUATION
vs V
A
V
• R
N
• I
• R
/(V
Noise/16mA • 10
FINE
Drift • T
Drift • T
Drift • T
REF
+
RTD MIN
Note (1)
Note (1)
Note (1)
Note (1)
Note (1)
Note (1)
Note (1)
RTD MIN
RTD MIN
) • V
A
IN MAX
/(V
/16mA • 10
• R
IN MAX
IN MAX
RTD MIN
) • 10
/(V
+
/(V
/(V
/16mA • 10
A
A
A
IN MAX
IN MAX
IN MAX
) • 10
6
) • 10
/(V
6
IN
) • 10
6
) • 10
) • 10
6
IN MAX
www.ti.com
= 40mW. Register 06 = 0
6
6
6
6
6
6
)
15ppm • 20 C • 518.9 A • 100/40mV
SAMPLE ERROR CALCULATION
assumption is made that all errors are positive and additive.
As the various error sources are independent, a closer
approximation to nominal performance might be to accumu-
late the errors with a root-sum-square calculation.
0.02 V/ C • 20 C/40mV • 106
0.015 A • 100 /40mV • 10
0.1V/100M
5 V/V • 0.1V/0.04V • 10
96nA • 100 /40mV • 10
2 • 1.8 A/16mA • 10
0.01%/100% • 10
1.1 A/16mA • 10
6 V/40mV • 10
35ppm • 20 C
30ppm • 20 C
Total Excitation Error:
Note (2)
Note (1)
H
03; Register 11 = 0
Total Output Error:
Total Noise Error:
Total Input Error:
• 100 /40mV
Total Gain Error:
Total Drift Error:
TOTAL ERROR:
6
A
6
6
) 20 C; Supply Voltage Change ( V
6
6
6
6
H
11; Register 13 = 0
CALIBRATED ERROR
(ppm of Full Scale)
0.28% (0.20%)
2792 (1997)
H
242.5
FC; Register 14 = 0
1950
12.5
12.5
37.5
68.5
240
100
100
225
231
700
390
600
250
150
256
2.5
10
0
0
0
0
0
0
6
+
(3)
) 5V; Common-
(3)
H
21
70.