MCP4341数字电位器中PXA，PXW和PXB引脚的最大电流±2.5 mA指在AND中吗？

它表示正负，所以覆盖了两个方向。



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    It says plus or minus, so that covers both directions.
 

我明白了，所以数据表的这一部分是指SPI引脚？最大输出电流由任何输出引脚沉没，25毫秒输出电流由任何输出引脚……25…



      以下为原文

    I see.
 
So this part of the data sheet refers to the SPI pins?
 
Maximum output current sunk by any Output pin
......................................................................................25 mA
Maximum output current sourced by any Output pin
......................................................................................25 mA

是的，但是这些是引脚硬件的最大额定值，在短路情况下考虑，或者是高输出驱动到低输出的情况。在加载这样的电流时，没有任何关于信号电平的说明。所有的MOSFET晶体管在导通时都具有内阻。在功率晶体管的数据表中规定了RDS ON，对于大功率器件，可以是一些毫欧姆。在微控制器或数字电位器中，数字I/O引脚的类似特性可能在一些PIC器件具有显示引脚电压作为负载电流的功能的图表。高侧输出晶体管可能比低侧晶体管具有更多的电阻。当引脚短路到GND并且驱动高电平时，一些器件实际上是短路的，而不是当引脚。被短路到VDD和驱动Low。迈西尔



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Yes, but those are maximum ratings for the pin hardware,
for consideration in case of short circuit conditions, or a case like a High Output driving into a Low Output.
Does not say anything about signal level when loaded with such a current.
Datasheet will have other specs for what current may be loaded while maintaining rated signal level.
 
All MOSFET transistors have internal resistance when conducting.
Rds on is specified in datasheet for power transistors, and may be some milliohm for a large power device.
In a microcontroller or digital pot, the similar property for digital I/O pins may be in the range of a few hundred Ohm.
 
Some PIC devices have diagrams showing pin voltage as function of load current.
High-side output transistor may have more resistance than low-side transistor.
Some devices are practically short-circuit proof when a pin is shorted to GND and driven High,
Not so, when pin is shorted to Vdd and driven Low.
 
   Mysil

我需要从罐子里抽出5Ma，我能做些什么吗？如果我使用了一个四叉树，把PXA、PXB和PXW管脚并联，这会有什么区别吗？该应用是MIDI，5Ma是MIDI规范中所需的电流，然而，当在商业MIDI设备中测试时，只需要画几毫安。所以，我想知道在这个应用中是否可以。有什么想法吗？



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    I need to draw 5mA through the pot, is there anything I can do. What if I used a quadpot and put the PxA, PxB and PxW pins in parallel, would that make any difference?
 
The application is a MIDI one, and 5mA is the current required in the MIDI specification, however when tested in a commercial MIDI device, there is only a couple of milliamps being drawn. So, I wonder if it might be OK in this application. Any ideas?

MIDI规范的哪一部分？你不是把MIDI数据信号通过锅，是吗？



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What part of the MIDI specification?
You're not putting the MIDI data signal through the pot are you?
 

不，5伏用于MIDI输出插座的引脚4。



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    No. The 5volts is used on pin 4 of a MIDI out socket.

5Ma电流环型。逻辑0是当前的。



      以下为原文

    5mA current loop type. Logical 0 is current ON.
   Attached Image(s)

那你为什么要在那里放个数字罐呢？当你测量“只有几毫安”时，是信号传输时的平均电流，还是峰值？当没有发送任何数据时，它应该为零。



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    So why would you put a digipot there?
When you measured "only a couple of milliamps", was that the average current while a signal was being transmitted, or the peak?
It should be zero when nothing is being sent.
 

用万用表阅读，我想这是平均值。为什么要放数字罐呢？罐已经在那里，MIDI是事后的想法，随着硬件已经被设置，并且可以访问一些数字开关，我可以将5伏特路由到那个点。所以这是在没有修改硬件的情况下获得5伏特的唯一方法。



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    read with a multimeter so I guess that is the average.
 
Why put a digital pot there? The pot is already there, MIDI was an afterthought, and with the hardware already being set, and having access to some digital switches, I can route the 5 volts to that point. So it is the only way of getting 5 Volts at that point without modifying the hardware.

并联的数字盆是否能像普通电阻器一样实现电流共享？



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    Does putting digital pots in parallel enable current sharing like usual resistors?