參數(shù)資料
型號： LMP90078MH/NOPB
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 模擬信號調(diào)理
英文描述： SPECIALTY ANALOG CIRCUIT, PDSO28
封裝： LEAD FREE, PLASTIC, MO-153, TSSOP-28
文件頁數(shù)： 24/62頁
文件大小： 1721K
代理商： LMP90078MH/NOPB
16.4 SENSOR INTERFACE
The LMP90080/LMP90078 contains two excitation currents
(IB1 & IB2) for sourcing external sensors, and the LMP900xx
contain two burnout currents for sensor diagnostics. They are
described in the next sections.
16.4.1 IB1 & IB2 - Excitation Currents (LMP90080/
LMP90078)
IB1 and IB2 can be used for providing currents to external
sensors, such as RTDs or bridge sensors. 100A to 1000A,
in steps of 100A, can be sourced by programming the
ADC_AUXCN: RTD_CUR_SEL bits.
Refer to Section 17.6.1 3–Wire RTD to see how IB1 and IB2
can be used to source a 3-wire RTD.
16.4.2 Burnout Currents
As shown in Figure 16, the LMP900xx contains two internal
10 A burnout current sources, one sourcing current from VA
to VINP, and the other sinking current from VINN to ground.
These currents are used for sensor diagnostics and can be
enabled for each channel using the CHx_INPUTCN:
BURNOUT_EN bit.
30169780
FIGURE 16. Burnout Currents
Burnout Current Injection:
Burnout currents are injected differently depending on the
channel scan mode selected.
When BURNOUT_EN = 1 and the device is operating in
ScanMode0, 1, or 2, the burnout currents are injected into all
the channels for which the BURNOUT_EN bit is selected.
This will cause problems and hence in this mode, more than
one channel should not have its BURNOUT_EN bit selected.
Also, the burnout current will interfere with the signal and in-
troduce a fixed error depending on the particular external
sensor.
When BURNOUT_EN = 1 and the device is operating in
ScanMode3, burnout currents are injected into the last sam-
pled channel on a cyclical basis (Figure 17). In this mode,
burnout currents injection is truly done in the background
without affecting the accuracy of the on-going conversion.
Operating in this mode is recommended.
30169781
FIGURE 17. Burnout Currents Injection for ScanMode3
16.4.3 Sensor Diagnostic Flags
Burnout currents can be used to verify that an external sensor
is still operational before attempting to make measurements
on that channel. A non-operational sensor means that there
is a possibility the connection between the sensor and the
LMP900xx is open circuited, short circuited, shorted to VA or
GND, overloaded, or the reference may be absent. The sen-
sor diagnostic flags diagram can be seen in Figure 18.
www.national.com
30
LMP90080/LMP90079/LMP90078/LMP90077
相關(guān)PDF資料
PDF描述
LMP90079MH/NOPB SPECIALTY ANALOG CIRCUIT, PDSO28
LMP90079MHE/NOPB SPECIALTY ANALOG CIRCUIT, PDSO28
LMP90078MHX/NOPB SPECIALTY ANALOG CIRCUIT, PDSO28
LMP90078MHE/NOPB SPECIALTY ANALOG CIRCUIT, PDSO28
LMP90079MHX/NOPB SPECIALTY ANALOG CIRCUIT, PDSO28
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LMP90078MHX/NOPB 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-32
LMP90079 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Sensor AFE System: Multi-Channel, Low-Power 16-Bit
LMP90079MH/NOPB 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-32
LMP90079MHE/NOPB 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-32
LMP90079MHX/NOPB 功能描述:模數(shù)轉(zhuǎn)換器 - ADC RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 結(jié)構(gòu):Sigma-Delta 轉(zhuǎn)換速率:125 SPs to 8 KSPs 分辨率:24 bit 輸入類型:Differential 信噪比:107 dB 接口類型:SPI 工作電源電壓:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-32
發(fā)布緊急采購，3分鐘左右您將得到回復。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*