PIC16F87A能支持模拟引脚的5.6V吗？

嗨，检查你的图片的数据表结束时的电气规格，你会发现这个信息



      以下为原文

    Hi,
check the electrical specifications at the end of the datasheet of your PIC, you will find this information
Regards
 
 

…将是“不”



      以下为原文

    ...which will be "no"

我真希望这是一个试题。



      以下为原文

    I do hope this is an exam question

实际上，PIC16F87在VDD上相对于VSS具有绝对最大的7.5伏电压。而且大多数引脚的电压限制在VDD+0.3V，所以如果电源电压为6V左右，ADC可能能够容忍5.6V。最大推荐电源是5.5V，所以在这种情况下5.6V就可以了。然而，ADC在该输入电压上可能不是线性的。PIC18F2550系列也容忍7.5V，而新设备如PIC16F1455仅限于65.V。



      以下为原文

    Actually, the PIC16F877 has an absolute maximum of 7.5 volts on Vdd with respect to Vss. And the voltage on most pins is limited to Vdd+0.3V. So the ADC may be able to tolerate 5.6V if the supply voltage is 6V or so. Maximum recommended supply is 5.5V, so in that case 5.6V would be OK. However, the ADC might not be linear at that input voltage. The PIC18F2550 family also tolerates 7.5V, while newer devices such as PIC16F1455 are limited to 6.5V.

而任何将PIC16F87A设计成新产品的人头上都会有石头。微芯片仍然出售它们来支持旧的设计。较新的芯片更便宜、更快、更容易使用。



      以下为原文

    ...and anyone who designs a PIC16F877A into a new product has rocks in their head.
Microchip only still sell them to support old designs.
Newer chips are cheaper, faster, and much easier to work with.
 

HI，PIC微控制器在调节器或比ADC参考电压高的任何电压下测量其自身电源电压的一种更为正常的方式是布置一个分压器来馈送ADC输入。一个具有高值电阻器的分压器，也可以帮助保护MCU，如果伏特。Ge要测量，即使MCU是不供电的。许多PIC设备将容忍10千欧等效源阻抗ADC输入，DC或低频测量。10 KOHM等效阻抗可以通过2个20分贝的电阻连接在分压器中，以及在网络上的老教程，以及小规模零售商遗留下来的旧库存，以及在学校潜伏的陈旧的实验室练习板。迈西尔



      以下为原文

    Hi,
A more normal way for a PIC microcontroller to measure it's own power supply voltage before a regulator,
or any voltage higher than the ADC reference voltage, is to arrange a voltage divider feeding the ADC input.
 
A voltage divider with high value resistors, may also help protect the MCU, if voltage to be measured is present, even if the MCU is unpowered.
Many PIC devices will tolerate 10 kOhm equivalent source impedance for ADC inputs, for DC or low frequency measurements. 10 kOhm equivalent impedance may be obtained by 2 resistors of 20 kOhm connected in a voltage divider.
 

And old tutorials around the web, and old stock remaining with small scale retailers, and obsolete lab exercise boards lurking in school.
 
   Mysil

您可能想阅读数据表中的第12.9章：



      以下为原文

    You may want to read the chapter 12.9 in the data-sheet:

应该是不可以的，电压最大是5.5V的