AD7794BRU: 6通道、低噪声、低功耗、24位Σ-Δ型ADC,内置片内仪表放大器和基准电压源
AD7794/AD7795均为适合高精度测量应用的低功耗、低噪声、完整模拟前端,内置一个低噪声24位/16位Σ-Δ型ADC,其中含有6个差分输入,还集成了片内低噪声仪表放大器,因而可直接输入小信号。
每款器件均内置一个精密低噪声、低漂移内部带隙基准电压源,也可采用最多两个外部差分基准电压。其它片内特性包括可编程激励电流源、熔断电流控制和偏置电压产生器,利用偏置电压产生器可将某一通道的共模电压设置为AVDD/2。低端电源开关可用来在两次转换之间关断桥式传感器,从而使系统功耗降至最低。AD7794/AD7795可以采用内部时钟或外部时钟工作,输出数据速率可在4.17 Hz至470 Hz的范围内变化。
两款器件均采用2.7 V至5.25 V电源供电。B级器件（AD7794和AD7795）的额定温度范围为-40°C至+105°C,而C级器件（AD7794）的额定温度范围为-40°C至+125°C,这些器件的典型功耗为400 uA,采用24引脚TSSOP封装。
The AD7794/AD7795 are low power, low noise, complete analog front ends for high precision measurement applications. They contain a low noise, 24-/16-bit Σ-Δ ADC with six differential inputs. The on-chip low noise instrumentation amplifier means that signals of small amplitude can be interfaced directly to the ADC.
Each device contains a precision, low noise, low drift internal band gap reference, and can also accept up to two external differential references. Other on-chip features include programmable excitation current sources, burnout currents, and a bias voltage generator that is used to set the common-mode voltage of a channel to AVDD/2. The low-side power switch can be used to power down bridge sensors between conversions, minimizing the system’s power consumption. The AD7794/AD7795 can operate with either an internal clock or an external clock. The output data rate from each part can vary from 4.17 Hz to 470 Hz.
Both parts operate with a power supply from 2.7 V to 5.25 V. The B-grade parts (AD7794 and AD7795) are specified for a temperature range of -40°C to +105°C while the C-grade part (AD7794) is specified for a temperature range of -40°C to +125°C. They consume a current of 400 μA typical and are housed in a 24-lead TSSOP.
产品应用领域 Applications
- 温度测量
- 压力测量
- 电子秤
- 应变计传感器
- 气体分析
产品应用领域 Applications
- Temperature measurement
- Pressure measurement
- Weigh scales
- Strain gage transducers
- Gas analysis
AD7794BRU 特点
- 最高23位有效分辨率
- 均方根（RMS）噪声：40 nV（4.17 Hz时）,85 nV（16.7 Hz时）
- 功耗：400 uA（典型值）
- 省电模式：最大1 uA
- 低噪声可编程增益仪表放大器
- 带隙基准电压源,典型漂移值为4 ppm/°C
- 更新速率：4.17 Hz～470 Hz
- 6个差分模拟输入
- 内部时钟振荡器
- 50 Hz/60 Hz同时抑制
- 基准电压检测
- 可编程电流源
- Up to 23 effective bits
- RMS noise: 40 nV @ 4.17 Hz, 85 nV @ 16.7 Hz
- Current: 400 μA typical
- Power-down: 1 μA maximum
- Low noise, programmable gain, instrumentation amp
- Band gap reference with 4 ppm/°C drift typical
- Update rate: 4.17 Hz to 470 Hz
- Six differential analog inputs
- Internal clock oscillator
- Simultaneous 50 Hz/60 Hz rejection
- Reference detect
- Programmable current sources
AD7794BRU 功能框图
| 产品型号 | 产品状态 | 封装 | 引脚 | 温度范围 |
|---|---|---|---|---|
| AD7794BRU | Prodn | 24 ld TSSOP | 24 | 工业 |
| AD7794BRU-REEL | Prodn | 24 ld TSSOP | 24 | 工业 |
| AD7794BRUZ | Prodn | 24 ld TSSOP | 24 | 工业 |
| AD7794BRUZ-REEL | Prodn | 24 ld TSSOP | 24 | 工业 |
| AD7794CRUZ | Prodn | 24 ld TSSOP | 24 | 工业 |
| AD7794CRUZ-REEL | Prodn | 24 ld TSSOP | 24 | 工业 |
| EVAL-AD7794EBZ | Prodn | EVALUATION BOARDS | - | 待定 |
AD7794BRU 应用技术支持与电子电路设计开发资源下载
- AD7794 数据手册DataSheet下载. pdf
- Analog Devices, Inc.ADI 美国模拟器件公司产品订购手册 .PDF
- ADC模数转换器选型指南 . PDF