參數(shù)資料
型號(hào)： MAX1459
廠商： Maxim Integrated Products, Inc.
英文描述： 2-Wire, 4-20mA Smart Signal Conditioner
中文描述： 2線、4-20mA智能信號(hào)調(diào)理器
文件頁(yè)數(shù)： 18/24頁(yè)
文件大?。?/td> 243K
代理商： MAX1459
M
2-Wire, 4–20mA
Smart Signal Conditioner
18
______________________________________________________________________________________
where OTC is the sensor offset TC error as a ppm/°C of
OUTFSO (Table 8),
T is the operating temperature
range in °C, and OFFTC COEF is the numerical decimal
value to be loaded into the DAC. For positive values,
set the OFFTC sign bit high; for negative values, set the
OFFTC sign bit low. If the absolute value of the OFFTC
COEF is larger than 4096, the sensor has a very large
offset TC error, which the MAX1459 is unable to com-
pletely correct without the use of a temperature sensor.
FSO Calibration
Perform FSO calibration at room temperature with a full-
scale sensor excitation:
1) Set FSOTC COEF to 1000.
2) At T1, adjust FSO DAC until V
BDRIVE
is about 2.5V.
3) Adjust offset DAC (and OFFSET sign bit, if needed)
until the T1 offset voltage is 0.5V (see
OFFSET
Calibration
section).
4) Measure the full-span output (measuredV
FSO
).
5) Calculate the ideal bridge voltage, V
BIDEAL
(T1),
using the following equation:
Note:
If V
BIDEAL
(T1) is outside the allowable bridge
voltage swing of (V
SS
+ 1.3V) to (V
DD
- 1.3V), readjust
the PGA gain setting. If V
BIDEAL
(T1) is too low,
decrease the PGA gain setting by one step and return
to step 2. If V
BIDEAL
(T1) is too high, increase the PGA
gain setting by one step and return to step 2.
6) Set V
BIDEAL
(T1) by adjusting the FSO DAC.
7) Readjust Offset DAC until the V
OUT
= 0.5V (see
OFFSET Calibration
section).
Three-Step FSOTC Compensation
Step 1
Use the following procedure to determine FSOTC
COEF; four variables, A–D, will be used:
1) Name the existing FSO DAC coefficient A.
2) Change FSOTC DAC to 3000.
3) Adjust FSO DAC until V
BDRIVE
(T1) is equal to
V
BIDEAL
(T1).
4) Name the new FSO DAC coefficient B.
5) Readjust the offset voltage (by adjusting the Offset
DAC), if required, to V
OUT
= 0.5V.
At this point, it is important that no other changes be
made to the offset or offset TC DACs until the Offset TC
compensation step has been completed.
Step 2
To complete linear FSOTC compensation, take data
measurements at a second temperature, T2
.
The follow-
ing equation and procedure are suitable for any two
arbitrary temperatures where T2 > T1. The following
steps are performed at temperature T2:
1) Measure the full-span output (measuredV
FSO
(T2)).
2) Calculate V
BIDEAL
(T2) using the following equation:
3) Set V
BIDEAL
(T2) by adjusting the FSO DAC.
4) Name the current FSO DAC coefficient D.
5) Change FSOTC DAC to 1000.
6) Adjust FSO DAC until V
BDRIVE
is equal to
V
BIDEAL
(T2).
7) Name the FSO DAC coefficient C.
Step 3
Insert the data previously obtained from steps 1 and 2
into the following equation to compute FSOTC COEF:
1) Load this FSOTC COEF value into the FSOTC DAC.
2) Adjust the FSO DAC until V
BDRIVE
(T2) is equal to
V
BIDEAL
(T2).
This completes both FSO calibration and FSO TC com-
pensation.
Offset TC Compensation
The offset voltage at T1 was previously set to 0.5V;
therefore, any variation from this voltage at T2 is an
offset TC error. Perform the following steps:
1) Measure the offset voltage at T2.
2) Use the following equation to compute the correc-
tion required:
FSOTC COEF
1000 B-D
(
3000 C- A
)
+
B-D
C- A
=
)
+
)
)
V
T2
V
1
desiredV
- measuredV
measuredV
T2
T2
BIDEAL
BDRIVE
FSO
FSO
)
FSO
(
)
=
+
(
)
(
x
V
1
( )
=
V
1
desiredV
- measuredV
T
measuredV
T
BIDEAL
BDRIVE
FSO
FSO
FSO
1
1
+
( )
( )
x
相關(guān)PDF資料
PDF描述
MAX1459AAP 2-Wire, 4-20mA Smart Signal Conditioner
MAX1459CAP 2-Wire, 4-20mA Smart Signal Conditioner
MAX1460CCM Low-Power, 16-Bit Smart ADC
MAX1460 Low-Power, 16-Bit Smart ADC
MAX1462 Low-Voltage, Low-Power, 16-Bit Smart ADC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX14590ETA+ 制造商:Maxim Integrated Products 功能描述:HIGH-CURRENT OVERVOLTAGE PROTECTOR WITH ADJUSTABLE OVLO - Rail/Tube
MAX14590ETA+T 制造商:Maxim Integrated Products 功能描述:HIGH-CURRENT OVERVOLTAGE PROTECTOR WITH ADJUSTABLE OVLO - Tape and Reel
MAX14591EETA+ 制造商:Maxim Integrated Products 功能描述:HIGH SPEED, OPEN DRAIN CAPABLE LOGIC LEVEL TRANSLATOR - Rail/Tube
MAX14591EETA+T 制造商:Maxim Integrated Products 功能描述:HIGH SPEED, OPEN DRAIN CAPABLE LOGIC LEVEL TRANSLATOR - Tape and Reel
MAX14591EEWA+ 制造商:Maxim Integrated Products 功能描述:HIGH SPEED, OPEN DRAIN CAPABLE LOGIC LEVEL TRANSLATOR - Rail/Tube
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*