AD7712AR-REEL7: 内置2个模拟输入通道的CMOS、24位Σ-Δ型信号调理ADC
AD7712是一款适合低频测量应用的完整模拟前端,具有两个模拟输入通道,可以直接接受来自传感器的低电平信号,也可以接受高电平（±4 × VREF）信号,并产生串行数字输出。它采用Σ-Δ转换技术,可实现最高24位无失码性能。低电平输入信号加在一个以模拟调制器为基础的专有可编程增益前端。经过衰减的高电平信号也可加在同一调制器。调制器输出由片内数字滤波器处理。此数字滤波器的第一个陷波可通过片内控制寄存器进行编程,以便对滤波器截止和建立时间进行调整。
一般而言,其中一个通道将用作主通道,而另一个通道将用作辅助输入,用来定期检测第二电压输入。如果低电平模拟输入上的输入信号高于-30 mV,则该器件可采用单电源供电（将VSS引脚与AGND相连）。将VSS引脚接负电压时,该器件可转换低至-VREF的输入信号。此输入低电平和基准电压均可为差分输入。
AD7712非常适合基于微控制器的智能系统应用。利用双向串行端口,可在软件中进行输入通道选择、增益设置和信号极性配置。AD7712还包含自校准、系统校准和后台校准选项,同时允许用户读取和写入片内校准寄存器。
CMOS构造可确保低功耗,硬件可编程省电模式则将待机功耗降至仅100 µW（典型值）。该器件提供两种封装：24引脚、0.3英寸宽、塑料密封双列直插式封装（DIP）和24引脚小形集成封装（SOIC）。
The AD7712 is a complete analog front end for low frequency measurement applications. The device has two analog input channels and accepts either low level signals directly from a transducer or high level (±4 x VREF) signals and outputs a serial digital word. It employs a sigma-delta conversion technique to realize up to 24 bits of no missing codes performance. The low level input signal is applied to a proprietary programmable gain front end based around an analog modulator. The high level analog input is attenuated before being applied to the same modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via the on-chip control register allowing adjustment of the filter cutoff and settling time.
Normally, one of the channels will be used as the main channel with the second channel used as an auxiliary input to periodically measure a second voltage. The part can be operated from a single supply (by tying the VSS pin to AGND) provided that the input signals on the low level analog input are more positive than -30 mV. By taking the VSS pin negative, the part can convert signals down to -VREF on this low level input. This low level input, as well as the reference input, features differential input capability.
The AD7712 is ideal for use in smart, microcontroller-based systems. Input channel selection, gain settings and signal polarity can be configured in software using the bidirectional serial port. The AD7712 also contains self-calibration, system calibration and background calibration options and also allows the user to read and to write the on-chip calibration registers.
CMOS construction ensures low power dissipation and a hardware programmable power-down mode reduces the standby power consumption to only 100 µW typical. The part is available in a 24-pin, 0.3 inch wide, plastic and hermetic dual-in-line package (DIP) as well as a 24-lead small outline (SOIC) package.
AD7712AR-REEL7 特点
- 电荷平衡ADC
- 24位无失码
- ±0.0015%非线性度 - 高电平和低电平模拟输入通道
- 可编程增益（两个输入均适用）
- 增益范围：1至128
- 差分输入适用于低电平通道 - 内置可编程滤波截止的低通滤波器
- 读/写校准系数
- 双向微控制器串行接口
- 内部、外部基准电压选择
- 单电源或双电源供电
- 低功耗（典型值25 mW）,
带省电模式（典型值100 µW） - Charge Balancing ADC
- 24 Bits No Missing Codes
- ±0.0015% Nonlinearity - High Level and Low Level Analog Input Channels
- Programmable Gain for Both Inputs
- Gains from 1 to 128
- Differential Input for Low Level Channel - Low-Pass Filter with Programmable Filter Cutoffs
- Ability to Read/Write Calibration Coefficients
- Bidirectional Microcontroller Serial Interface
- Internal/External Reference Option
- Single- or Dual-Supply Operation
- Low Power (25 mW typ) with Power-Down Mode (100 µW typ)
AD7712AR-REEL7 功能框图
| 产品型号 | 产品状态 | 封装 | 引脚 | 温度范围 |
|---|---|---|---|---|
| AD7712AN | 量产 | 24 ld PDIP | 24 | 工业 |
| AD7712ANZ | 量产 | 24 ld PDIP | 24 | 工业 |
| AD7712AQ | 量产 | CERDIP GLASS SEAL | 24 | 工业 |
| AD7712AR | 量产 | 24 ld SOIC - Wide | 24 | 工业 |
| AD7712AR-REEL7 | 量产 | 24 ld SOIC - Wide | 24 | 工业 |
| AD7712ARZ | 量产 | 24 ld SOIC - Wide | 24 | 工业 |
| AD7712ARZ-REEL | 量产 | 24 ld SOIC - Wide | 24 | 工业 |
| AD7712ARZ-REEL7 | 量产 | 24 ld SOIC - Wide | 24 | 工业 |
| AD7712SQ | 量产 | CERDIP GLASS SEAL | 24 | 军用 |
AD7712AR-REEL7 应用技术支持与电子电路设计开发资源下载
- AD7712 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
