ADI ADGS1408(9)SPI接口多路复接器解决方案

ADI公司的ADGS1408/ADGS1409是包含有八个单路和四个差分通路的模拟复接器，SPI接口控制模拟开关，具有很好的误差检测特性如循环冗余检查（CRC）误差检测，无效读/写地址检测，以及SCLK计数误差检测。支持突发模式和菊花链模式，工作电压±15 V，±5 V和+12 V，25℃时的开态电阻4Ω，主要用在自动测试设备（ATE），数据采集系统，通信系统，取样和保持系统，音频信号路由，视频信号路由，电池为能源系统，以及继电器替代品。本文介绍了ADGS1408/ADGS1409产品亮点和主要特性，功能框图，以及EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ主要特性，电路图，材料清单和PCB设计图。

The ADGS1408/ADGS1409 are analog multiplexers comprising eight single channels and four differential channels， respectively. A serial peripheral interface （SPI） controls the switches. The SPI interface has robust error detection features such as cyclic redundancy check （CRC） error detection， invalid read/write address detection， and SCLK count error detection. It is possible to daisy-chain multiple ADGS1408/ADGS1409 devices together. Daisy-chain mode enables the configuration of multiple devices with a minimal amount of digital lines. The ADGS1408/ADGS1409 can also operate in burst mode to decrease the time between SPI commands. iCMOS construction ensures ultra low power dissipation， making the devices ideally suited for portable and battery-powered instruments. Each switch conducts equally well in both directions when on， and each switch has an input signal range that extends to the supplies. In the off condition， signal levels up to the supplies are blocked. The on-resistance profile is flat over the full analog input range， which ensures linearity and low distortion when switching audio signals.

ADGS1408/ADGS1409产品亮点：

1. SPI interface removes the need for parallel conversion， logic traces， and reduces GPIO channel count.

2. Daisy-chain mode removes additional logic traces when multiple devices are used.

3. CRC error detection， invalid read/write address detection， and SCLK count error detection ensure a robust digital interface.

4. CRC and error detection capabilities allow the use of the ADGS1408/ADGS1409 in safety critical systems. 5. Minimal distortion.

ADGS1408/ADGS1409主要特性：

SPI interface with error detection

Includes CRC， invalid read/write address， and SCLK count error detection

Supports burst mode and daisy-chain mode

Industry-standard SPI Mode 0 and SPI Mode 3 interface compatible

Round robin mode allows switching times comparable with a parallel interface

General-purpose digital outputs to control other devices， such as parallel switches from Analog Devices， Inc.

4 Ω typical on resistance at 25℃

0.5 Ω typical on-resistance flatness at 25℃

0.2 Ω typical on-resistance match between channels at 25°C VSS to VDD analog signal range

Fully specified at ±15 V， ±5 V， and +12 V

Power-up sequence of VDD， VSS， and GND before applying VL and digital/analog inputs

1.8 V logic compatibility with 2.7 V ≤ VL ≤ 3.3 V

24-lead LFCSP package

ADGS1408/ADGS1409应用：

Automated test equipment

Data acquisition systems

Battery-powered systems

Sample-and-hold systems

Audio signal routing

Video signal routing

Communications systems

Relay replacement

图1.ADGS1408功能框图

图2.ADGS1409功能框图

图3.ADGS1408控制ADG758电路图

评估板EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ

The EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ are theevaluation boards for the ADGS1408/ADGS1409. TheADGS1408/ADGS1409 are low RON， 8:1/dual 4:1 multiplexerscontrolled by a serial peripheral interface （SPI）。 The SPI has robust error detection features， including cyclic redundancy check （CRC） error detection， invalid read/write addressdetection， and serial clock （SCLK） count error detection. It ispossible to daisy-chain multiple ADGS1408/ADGS1409 devicestogether to enable the configuration of multiple devices with aminimal amount of digital lines. The ADGS1408/ADGS1409also support burst mode， which decreases the time between SPI commands. Figure 1 and Figure 2 shows the EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ board photographs. The EVAL-ADGS1408SDZ/ EVAL-ADGS1409SDZ are controlled by the EVAL-SDP-CB1Zsystem demonstration platform （SDP）， which connects to a PC via a USB port. The ADGS1408/ADGS1409 is on the center of the evaluation board， and wire screw terminals are provided to connect to each of the source and drain pins. Three screwterminals power the device and， if required， a fourth terminal provides users with a defined digital logic supply voltage.

Alternatively， the digital logic supply voltage can be supplied from the SDP-B board. Consult the ADGS1408/ADGS1409 data sheet （available from Analog Devices， Inc.） in conjunction with this user guide when working with the evaluation board. The evaluation board interfaces to the USB port of a PC via the SDP-B board. The SDP-B controller board （EVAL-SDP-CB1Z）is available for order at

EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ主要特性：

SPI interface with error detection

Includes CRC error detection， invalid read/write addressdetection， and SCLK count error detection Analog supply voltages

Dual supply： ±15 V Single supply： 12 V PC control in conjunction with evaluation software EVALUATION KIT CONTENTS EVAL-ADGS1408SDZ/EVAL-ADGS1409SDZ

图4.EVAL-ADGS1408SDZ外形图

图5.EVAL-ADGS1409SDZ外形图

图6.EVAL-ADGS1408SDZ电路图-主器件（1）

图7.EVAL-ADGS1408SDZ电路图-主器件（2）

图8.EVAL-ADGS1408SDZ电路图-电源和硬件重置

图9.EVAL-ADGS1408SDZ电路图-SDP连接器

图10.EVAL-ADGS1408SDZ PCB设计图-丝印

图11.EVAL-ADGS1408SDZ PCB设计图-顶层

图12.EVAL-ADGS1408SDZ PCB设计图-层2

图13.EVAL-ADGS1408SDZ PCB设计图-层3

图14.EVAL-ADGS1408SDZ PCB设计图-底层

图15.EVAL-ADGS1409SDZ电路图-主器件（1）

图16.EVAL-ADGS1409SDZ电路图-主器件（2）

图17.EVAL-ADGS1409SDZ电路图-电源和硬件重置

图18.EVAL-ADGS1409SDZ电路图-SDP连接器

EVAL-ADGS1408/9SDZ材料清单：

图19.EVAL-ADGS1409SDZ PCB设计图-丝印

图20.EVAL-ADGS1409SDZ PCB设计图-顶层

图21.EVAL-ADGS1409SDZ PCB设计图-层2

图22.EVAL-ADGS1409SDZ PCB设计图-层3

图23.EVAL-ADGS1409SDZ PCB设计图-底层