參數(shù)資料
型號: ADS1000A0IDBVR
廠商: Analog Devices, Inc.
英文描述: LOW POWER, 12-Bit ANALOG-TO-DIGITAL CONVERTER with I2C⑩ INTERFACE
中文描述: 低功耗,12位模擬數(shù)字轉(zhuǎn)換接口的I2C⑩
文件頁數(shù): 13/17頁
文件大小: 240K
代理商: ADS1000A0IDBVR
www.ti.com
LOW-SIDE CURRENT MONITOR
Figure 13
shows a circuit for a low-side shunt-type
current monitor. The circuit reads the voltage across
a shunt resistor, which is sized as small as possible
while still giving a readable output voltage. This
voltage is amplified by an OPA335 low-drift op-amp,
and the result is read by the ADS1000.
1
2
3
6
5
4
V
IN
-
V
IN+
SCL
GND
V
DD
SDA
ADS1000
V
DD
Output
Codes
0
-
2048
Filter Capacitor
33pF to 100pF
(typ.)
0V
V
Single-Ended
-
DD
NOTES: (1) Pull-down resistor to allow accurate swing to 0V.
(2) R is sized for a 50mV drop at full-scale current.
V
Load
R
S
(2)
1k
W
G = 12.5
-
5V
OPA335
R
49.9k
3
W
(1)
FS = 0.63V
5V
5V
11.5k
W
ADS1000
I C
(PGA Gain = 8)
5V FS
ADS1000
SBAS357–SEPTEMBER 2006
input pins, usually V
IN–
, and applying the input signal
to V
. The single-ended signal can range from
–0.2V to V
DD
+ 0.3V. The ADS1000 loses no linearity
anywhere in its input range. Negative voltages
cannot be applied to this circuit because the
ADS1000 inputs can only accept positive voltages.
Figure 12. Measuring Single-Ended Inputs
The ADS1000 input range is bipolar differential with
respect
to
the
reference,
single-ended circuit shown in
Figure 12
covers only
half the ADS1000 input scale because it does not
produce differentially negative inputs; therefore, one
bit of resolution is lost. The DRV134 balanced line
driver can be employed to regain this bit for
single-ended signals.
that
is,
±V
.
The
Figure 13. Low-Side Current Measurement
It is recommended that the ADS1000 be operated at
a gain of 8. The gain of the OPA335 can then be set
lower. For a gain of 8, the op amp should be
configured to give a maximum output voltage of no
greater than 0.75V. If the shunt resistor is sized to
provide a maximum voltage drop of 50mV at
full-scale current, the full-scale input to the ADS1000
is 0.63V.
Negative input voltages must be level-shifted. A good
candidate for this function is the THS4130 differential
amplifier, which can output fully differential signals.
This device can also help recover the lost bit noted
previously
for
single-ended
Level-shifting can also be performed using the
DRV134.
positive
signals.
13
相關PDF資料
PDF描述
ADS1000A0IDBVRG4 LOW POWER, 12-Bit ANALOG-TO-DIGITAL CONVERTER with I2C⑩ INTERFACE
ADS1000A0IDBVT LOW POWER, 12-Bit ANALOG-TO-DIGITAL CONVERTER with I2C⑩ INTERFACE
ADS1000A0IDBVTG4 LOW POWER, 12-Bit ANALOG-TO-DIGITAL CONVERTER with I2C⑩ INTERFACE
ADSP-2100AJG Circular Connector; No. of Contacts:66; Series:MS27473; Body Material:Aluminum; Connecting Termination:Crimp; Connector Shell Size:18; Circular Contact Gender:Socket; Circular Shell Style:Straight Plug; Insert Arrangement:18-35 RoHS Compliant: No
ADSP-2100AKG Crimp Socket Contact Power Connection Type:Crimp Contact
相關代理商/技術參數(shù)
參數(shù)描述
ADS1000A0IDBVRG4 功能描述:模數(shù)轉(zhuǎn)換器 - ADC Low Power 12-Bit 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
ADS1000A0IDBVT 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit ADC with I2C Interface 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
ADS1000A0IDBVT 制造商:Texas Instruments 功能描述:A/D Converter (A-D) IC
ADS1000A0IDBVTG4 功能描述:模數(shù)轉(zhuǎn)換器 - ADC 12-Bit ADC with I2C Interface 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
ADS1000A0QDBVRQ1 功能描述:模數(shù)轉(zhuǎn)換器 - ADC AC Lo Cost 12B 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