参数资料
| 型号： | AD8555ARZ |
| 厂商： | Analog Devices Inc |
| 文件页数： | 20/28页 |
| 文件大小： | 0K |
| 描述： | IC AMP CHOPPER 2MHZ 10MA 8SOIC |
| 标准包装： | 98 |
| 系列： | DigiTrim® |
| 放大器类型： | 断路器（零漂移） |
| 电路数： | 1 |
| 转换速率： | 1.2 V/µs |
| 增益带宽积： | 2MHz |
| 电流 - 输入偏压： | 16nA |
| 电压 - 输入偏移： | 2µV |
| 电流 - 电源： | 2mA |
| 电流 - 输出 / 通道： | 10mA |
| 电压 - 电源，单路/双路(±)： | 2.7 V ~ 5.5 V |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 8-SO |
| 包装： | 管件 |
| 产品目录页面： | 771 (CN2011-ZH PDF) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页当前第20页第21页第22页第23页第24页第25页第26页第27页第28页
AD8555
Rev. A | Page 27 of 28
The bridge circuit with a sensitivity of 2 mV/V is excited by a
5 V supply. The full-scale output voltage from the bridge
(±10 mV) therefore has a common-mode level of 2.5 V. The
AD8555 removes the common-mode component and amplifies
the input signal by a factor of 200 (G1 = 4, G2 = 50, Offset =
128). This results in an output signal of ±2.0 V. In order to pre-
vent this signal from running into the AD8555’s ground rail, the
output offset voltage has to be raised to 2.5 V. This signal is
within the input voltage range of the ADC.
USING THE AD8555 WITH CAPACITIVE SENSORS
Figure 61 shows a crude way of using the AD8555 with capaci-
tive sensors. RP1 and RP2 are resistors implementing a potential
divider to bias VNEG to VDD/2. Recommended values range
from 1 kΩ to 1 MΩ. CS is the capacitive sensor, and RS is a shunt
resistor used to prevent leakage currents from integrating on
the sensor. The value of RS is application specific.
Note that although VNEG is tied to a dc voltage, the only
impedance across the capacitive sensor is RS. Therefore, the
only way for charge to leak away from CS is through RS, assum-
ing the input bias currents at VPOS and VNEG are negligible.
RS
CS
RP2
RP1
AD8555
VOUT
VDD
VPOS
VNEG
04598-0-059
Figure 61. Crude Way of Using the AD8555 with Capacitive Sensors
The weakness of the circuit in Figure 61 is that the AD8555
input bias current at VPOS flows into RS and creates a differen-
tial offset voltage between VPOS and VNEG. This differential
offset voltage is amplified by the AD8555. The input bias cur-
rent at VNEG, on the other hand, flows into RP1 and create a
common-mode shift. This has little impact on VOUT. Despite
this weakness, the arrangement in Figure 61 should work if the
user wants to minimize the number of components around the
sensor, and if the error introduced by the input bias current at
VPOS is considered negligible.
If greater accuracy is needed, the circuit in Figure 62 is recom-
way for the capacitive sensor to discharge is through (RS1 + RS2).
The input bias current at VPOS flows through RS2 and RP1, and
the input bias current at VNEG flows through RS1 and RP1. If RS1
is made equal to RS2 and if the input bias currents are equal, the
input bias currents give a common-mode shift at VPOS and
VNEG with no differential offset. This common-mode shift is
attenuated by the AD8555 common-mode rejection. Further-
more, changes in input bias current, e.g., with temperature,
manifest as an input common-mode change, also rejected by
the AD8555.
CS
RS2
RP2
RS1
RP1
AD8555
VOUT
VDD
VPOS
VNEG
04598-0-060
Figure 62. Recommended Way of Using the AD8555 with Capacitive Sensors
相关PDF资料 |
PDF描述 |
|---|---|
| LTC6254CMS#PBF | IC OPAMP R-R 720MHZ MSOP-16 |
| FG-8 | FINGER GUARD FOR FAN |
| TSW-126-14-T-S | CONN HEADER 26POS .100" SNGL TIN |
| TSW-126-08-T-S | CONN HEADER 26POS .100" SNGL TIN |
| TSW-107-08-T-D-RA | CONN HEADER 14PS .100 DL R/A TIN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| AD8555ARZ1 | 制造商:AD 制造商全称:Analog Devices 功能描述:Zero-Drift, Digitally Programmable Sensor Signal Amplifier |
| AD8555ARZ-REEL | 功能描述:IC AMP CHOPPER 2MHZ 10MA 8SOIC RoHS:是 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:DigiTrim® 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件 |
| AD8555ARZ-REEL1 | 制造商:AD 制造商全称:Analog Devices 功能描述:Zero-Drift, Digitally Programmable Sensor Signal Amplifier |
| AD8555ARZ-REEL7 | 功能描述:IC AMP CHOPPER 2MHZ 10MA 8SOIC RoHS:是 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:DigiTrim® 标准包装:50 系列:- 放大器类型:J-FET 电路数:2 输出类型:- 转换速率:3.5 V/µs 增益带宽积:1MHz -3db带宽:- 电流 - 输入偏压:30pA 电压 - 输入偏移:2000µV 电流 - 电源:200µA 电流 - 输出 / 通道:- 电压 - 电源，单路/双路(±):7 V ~ 36 V，±3.5 V ~ 18 V 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:8-DIP（0.300"，7.62mm） 供应商设备封装:8-PDIP 包装:管件 |
| AD8555ARZ-REEL71 | 制造商:AD 制造商全称:Analog Devices 功能描述:Zero-Drift, Digitally Programmable Sensor Signal Amplifier |
发布紧急采购，3分钟左右您将得到回复。