请问ADS8343和ADS8341有什么区别

看资料没看出个区别

The ADS8343 is a 4-channel, 16-bit sampling Analog-to-Digital (A/D) converter with a synchronous serial interface. Typical power dissipation is 8mW at a 100kHz throughput rate and a +5V supply. The reference voltage (V_REF) can be varied between 500mV and V_CC/2, providing a corresponding input voltage range of ±V_REF. The device includes a shutdown mode which reduces power dissipation to under 15µW. The ADS8343 is ensured down to 2.7V operation.

The ADS8341 is a 4-channel, 16-bit sampling Analog-to-Digital converter (A/D) with a synchronous serial interface. Typical power dissipation is 8mW at a 100kHz throughput rate and a +5V supply. The reference voltage (V_REF ) can be varied between 500mV and V_CC , providing a corresponding input voltage range of 0V to V_REF . The device includes a shutdown mode that reduces power dissipation to under 15µW. The ADS8341 is tested down to 2.7V operation.

 ADS8343是真双极性输入？怎么资料是下面红色字体那样写的?如果这里的±V_{REF是指参考com端的，即com接VREF，然后输入0-2VREF，那为何ADS8341的输入范围不是这样不同样有com端吗?}

ABSOLUTE MAXIMUM RATINGS(1)
+VCC to GND ........................................................................ –0.3V to +6V
Analog Inputs to GND ............................................ –0.3V to +VCC + 0.3V
Digital Inputs to GND ........................................................... –0.3V to +6V
Power Dissipation .......................................................................... 250mW
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................–40°C to +85°C
Storage Temperature Range .........................................–65°C to +150°C
Lead Temperature (soldering, 10s) ............................................... +300°C
NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.

 ADS8343是真双极性输入？怎么资料是下面红色字体那样写的?如果这里的±V_{REF是指参考com端的，即com接VREF，然后输入0-2VREF，那为何ADS8341的输入范围不是这样不同样有com端吗?}

ABSOLUTE MAXIMUM RATINGS(1)
+VCC to GND ........................................................................ –0.3V to +6V
Analog Inputs to GND ............................................ –0.3V to +VCC + 0.3V
Digital Inputs to GND ........................................................... –0.3V to +6V
Power Dissipation .......................................................................... 250mW
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................–40°C to +85°C
Storage Temperature Range .........................................–65°C to +150°C
Lead Temperature (soldering, 10s) ............................................... +300°C
NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.

一个双极性，一个单极性，不太好比较吧

你说的双极性是指真双极性吗?

输入量程是一样的VCC，因为要双极性，只能将参考电压变为0.5*VCC，这就是ADS8343的用法改变

ADS8343这款既可以单端输入也可以差分输入。不知你说的红色字体是什么意思，这里只是说明模拟输入的电压范围

ADS8343是双极性输入。

楼主，你的疑问可以通过下面这个图解释。

这里说的输入范围的正负范围是相对于common-mode voltage来说的。common-mode voltage的大小也会影响输入电压的范围。

但是Analog Inputs to GND ............................................ –0.3V to +VCC + 0.3V 指的是输入信号的模拟特性，必须在电压轨之内。

这里的双极性不是指模拟信号有0V以下的电压。只是以common-mode volatge为中心上下摆动。

你说的真双极性是想说以0V为中心的双极性，这里不是你想的那种真双极性。

其实极性这个概念本来就是相对的。只是楼主习惯了以0V为中心。

Gavin Ye

你说的双极性是指真双极性吗?

至于你说的为什么ADS8341也有同样com端为什么不行，这就涉及到芯片内部的设计，不是说有一样的引脚就是有一样的功能。

因为设计不一样，所以Vref的输入要求不一样，模拟输入信号的范围也不一样，这是针对不用的应用场景设计的。

楼主可以仔细阅读下两个手册中的“ANALOG INPUT” “REFERENCE INPUT”就能明白。

Gavin Ye

 ADS8343是真双极性输入？怎么资料是下面红色字体那样写的?如果这里的±V_{REF是指参考com端的，即com接VREF，然后输入0-2VREF，那为何ADS8341的输入范围不是这样不同样有com端吗?}

ABSOLUTE MAXIMUM RATINGS(1)
+VCC to GND ........................................................................ –0.3V to +6V
Analog Inputs to GND ............................................ –0.3V to +VCC + 0.3V
Digital Inputs to GND ........................................................... –0.3V to +6V
Power Dissipation .......................................................................... 250mW
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................–40°C to +85°C
Storage Temperature Range .........................................–65°C to +150°C
Lead Temperature (soldering, 10s) ............................................... +300°C
NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.

两个器件的基准范围是不一样的，两个器件都是可以双极性输入，也可以单极性输入，看你的接法。就是ads8343 可以是输入负的范围，而ADS8341 就是不可以的。  这就是所谓的真假双极性了。

你说的“ds8343 可以是输入负的范围，而ADS8341 就是不可以的”是指ds8343 输入端电压可以比com短电压低，而ds83431输入端电压只能比com端电压高?无论是ds8343 还是ds8341，输入电压都不能低于GND，这不叫真双极性吧。