简介
AD771x 系列是一组专为低频、高精度工业传感器应用而设计
的 ADC，图 1 显示了这些器件之一的框图。模拟前端在某些
情况下还包括传感器激励源，并且接受低电平信号，在信号
施加于 Σ-Δ 调制器前可通过内部可编程增益放大器进行放大。
出现在该调制器输出端的脉冲流施加于数字滤波器，从而产
生经过低通滤波的高分辨率串行输出。
transducer applications. Figure 1 shows a block diagram
of one of these devices. The analog front end, which in
some cases also includes excitation sources for sensors,
accepts low level signals that can be amplified by the
internal programmable gain amplifier before being
applied to a sigma-delta modulator. The pulse stream
appearing at the output of this modulator is applied to a
digital filter which produces a low-pass filtered, high
resolution, serial output.
∑-∆
MODULATOR
DIGITAL

AN-406：使用AD771x系列24位Σ-ΔADC.pdf
FILTER
SERIAL
OUTPUT
AIN(+)
AIN(–)
PGA
AD771x
Figure 1. AD771x Block Diagram 图 1. AD771x 框图
some cases also includes excitation sources for sensors,
accepts low level signals that can be amplified by the
internal programmable gain amplifier before being
applied to a sigma-delta modulator. The pulse stream
appearing at the output of this modulator is applied to a
digital filter which produces a low-pass filtered, high
resolution, serial output.
∑-∆
MODULATOR
DIGITAL
FILTER
SERIAL
OUTPUT
AIN(+)
AIN(–)
PGA
AD771x
Figure 1. AD771x Block Diagram