AD7738:8通道、8.5 kHz、24位Σ-Δ型ADC

AD7738: 8通道、8.5 kHz、24位Σ-Δ型ADC

AD7738是一款高精度、高吞吐量模拟前端,可实现真16位峰－峰值分辨率,及117 µs总转换时间（8.5 kHz通道切换）,非常适合高分辨率多路复用应用。

AD7738采用Σ-Δ架构,具有最高24位无失码性能。用户可通过简易数字接口对该器件进行配置,从而平衡噪声性能与数据吞吐量,实现最高15.4 kHz的转换速率。该模拟前端可配置为8个单端输入或4个全差分输入通道,输入范围包括单极性或双极性625 mV、1.25 V和2.5V,以及从AGND+200 mV至AVDD-300 mV范围的共模输入电压。同时提供多路复用器的输出引脚,方便用户在ADC输入信号之前,可预先进行增益编程或信号调节。差分基准电压输入具有“无基准电压”检测功能。此款ADC还支持按通道进行系统校准选项。数字串行接口可配置用于三线式操作,并且与微控制器和数字信号处理器兼容。所有接口输入均为施密特触发式。该器件的额定温度范围为–40°C至+105°C扩展工业温度范围,采用28引脚TSSOP封装。

The AD7738 is a high precision, high throughput analog front end. True 16-bit peak-to-peak resolution is achievable with a total conversion time of 117 µs (8.5 kHz channel switching) making it ideally suitable for high resolution multiplexing applications.

The AD7738 is based on a sigma-delta architecture and features up to 24 bits of no missing codes performance. The part can be configured via a simple digital interface, which allows users to balance the noise performance against data throughput up to a 15.4 kHz conversion rate. The analog front end features 8 single-ended or 4 fully differential input channels with unipolar or bipolar 625 mV, 1.25 V and 2.5V input ranges and accepts a common mode input voltage from 200 mV above AGND to AVDD-300 mV. The multiplexer output is pinned out externally allowing the user to implement programmable gain or signal conditioning before applying the input signal to the ADC. The differential reference input features “No Reference” detect capability. The ADC also supports per channel system calibration options.The digital serial interface can be configured for three-wire operation and is compatible with microcontrollers and digital signal processors. All interface inputs are Schmitt triggered.The part is specified for operation over the extended industrial temperature range of -40ºC to +105ºC and is available in 28-lead TSSOP package.

AD7738 特点

高分辨率ADC：
- 24位无失码
- ±0.0015%非线性度
优化快速通道开关：
- 18位峰－峰值分辨率（21位有效位、500 Hz）
- 16位峰－峰值分辨率（19位有效位、8.5Hz）
- 15位峰－峰值分辨率（18位有效位、15Hz）
- 片内按通道系统校准
可配置输入：
- 8个单端输入或4个全差分输入
输入范围：
- +625 mV、+1.25 V、+2.5 V、±625 mV、±1.25 V、±2.5 V
三线式串行接口：
- SPI®、QSPI™、MICROWIRE™、DSP兼容
- 施密特触发器逻辑输入
单电源工作：
- 5 V模拟电源
- 3 V或5 V数字电源
封装：28引脚TSSOP
High resolution ADC
- 24 bits no missing codes
- ±0.0015% Nonlinearity
Optimized for Fast Channel Switching
- 18-Bits p-p Resolution (21 Bits Effective) at 500 Hz
- 16-Bits p-p Resolution (19 Bits Effective) at 8.5 kHz
- 15-Bits p-p Resolution (18 Bits Effective) at 15 kHz
- On-Chip Per Channel System Calibration
Configurable Inputs
- 8 Single-Ended or 4 Fully Differential
Input Ranges
- +625 mV, +1.25 V, +2.5 V, ±625 mV, ±1.25 V, ±2.5 V
3-Wire Serial Interface
- SPI®, QSPI™, MICROWIRE™ and DSP Compatible
- Schmitt Trigger on Logic Inputs
Single-Supply Operation
- 5 V Analog Supply
- 3 V or 5 V Digital Supply
Package: 28-Lead TSSOP

AD7738 技术指标

Resolution (Bits): 24bit
# Chan: 8
Sample Rate: 3.05MSPS
Interface: Ser,SPI
Analog Input Type: Diff-Bip,Diff-Uni,SE-Uni
Ain Range: Bip 0.625,Bip 1.25,Bip 2.5V,Uni 0.625,Uni 1.25,Uni 2.5V
ADC Architecture: Sigma-Delta
Pkg Type: SOP

AD7738 功能框图

AD7738 芯片订购指南

产品型号	产品状态	封装	引脚	温度范围
AD7738BRU	Prodn	28 ld TSSOP	28	工业
AD7738BRU-REEL7	Prodn	28 ld TSSOP	28	工业
AD7738BRUZ	Prodn	28 ld TSSOP	28	工业
AD7738BRUZ-REEL	Prodn	28 ld TSSOP	28	工业
AD7738BRUZ-REEL7	Prodn	28 ld TSSOP	28	工业
EVAL-AD7738EB-U2	Prodn	EVALUATION BOARDS	-	待定
EVAL-AD7738EBZ	Prodn	EVALUATION BOARDS	-	待定