AD7747是一款高分辨率、Σ-Δ电容数字转换器(CDC),可直接与电容传感器的电容连接进行测量。该芯片还具有高分辨率(24位无失码、最高19.5位有效分辨率)、高线性度(±0.01%)和高精度(±10 fF工厂校准)等固有特性。AD7747的电容输入范围是±8 pF(可变),而且可接受最大17 pF共模电容(不可变),后者可以通过一个可编程片内数字电容转换器(CAPDAC)来平衡。AD7747针对一块极板接地的单端或差分输入电容传感器设计。对于浮动式(不接地)电容传感器,推荐使用AD7745或AD7746。
该器件内置一个片内温度传感器,其分辨率为0.1°C,精度为±2°C;还集成片内基准电压源和片内时钟发生器,因此在电容传感器应用中无需任何额外外部元件。此款器件配有一个标准电压输入,当与差分基准电压输入结合使用时,可方便地与一个外部温度传感器(如RTD、热敏电阻或二极管等)接口。AD7747具有一个双线式I^2C兼容串行接口,可采用2.7 V至5.25 V单电源供电,额定温度范围为-40°C至+125°C汽车电子温度范围,采用16引脚TSSOP封装。
The AD7747 is a high-resolution, Σ-Δ capacitance-to-digital converter (CDC). The capacitance to be measured is connected directly to the device inputs. The architecture features inherent high resolution (24-bit no missing codes, up to 19.5-bit effective resolution), high linearity (±0.01%), and high accuracy (±10 fF factory calibrated). The AD7747 capacitance input range is ±8 pF (changing), and it can accept up to 17 pF common-mode capacitance (not changing), which can be balanced by a programmable on-chip digital-to-capacitance converter (CAPDAC).
The AD7747 is designed for single-ended or differential capacitive sensors with one plate connected to ground. For floating (not grounded) capacitive sensors, the AD7745 or AD7746 are recommended.
The part has an on-chip temperature sensor with a resolution of 0.1°C and accuracy of ±2°C. The on-chip voltage reference and the on-chip clock generator eliminate the need for any external components in capacitive sensor applications. The part has a standard voltage input that, together with the differential reference input, allows easy interface to an external temperature sensor, such as an RTD, thermistor, or diode.
The AD7747 has a 2-wire, I^2C-compatible serial interface. The part can operate with a single power supply of 2.7 V to 5.25 V. It is specified over the automotive temperature range of -40°C to +125°C and is housed in a 16-lead TSSOP package.
汽车电子、工业和医疗系统,用于:
Automotive, industrial, and medical systems for:
产品型号 | 产品状态 | 封装 | 引脚 | 温度范围 |
---|---|---|---|---|
AD7747ARUZ | Prodn | 16 ld TSSOP | 16 | 工业 |
AD7747ARUZ-REEL | Prodn | 16 ld TSSOP | 16 | 工业 |
AD7747ARUZ-REEL7 | Prodn | 16 ld TSSOP | 16 | 工业 |
EVAL-AD7747EBZ | Prodn | EVALUATION BOARDS | - | 待定 |