dsPIC33EP512MU814和Vref，LM4040总是输出低电压

你好，我想用一个LM4040作为ADC的2.5V参考。串联电阻是1K（所以极化电流应该是800 UA，10X是LM4040所需要的）阴极连接到RA10/VREF+，RA9/VREF-连接到GND。RA9和RA10都被配置为输入，两者都是模拟的。两个ADCsHAVE的引用，如果我采用一个LM4040，在测试配置中输出2.5V（电阻和参考，3.3V电源），并把它放在电路中（相同的事情，但是100N的上限到GND，然后直接到VREF+PIN），电压输出大约是800毫伏。焊接似乎是可以的，我可以。没有看到或测量短路到相邻引脚（VREF和AVDD）的事实，AVDD和VREF+1K之间的电阻（AVDD和K之间的电阻）AVSS和VREF之间的电阻：138kDo，你有什么建议吗？我错过了什么？（我不知道，目前的内部VREF+引脚是XX MA，这就是为什么下降…没有在数据表中捕捉到类似的信息



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    Hi,
i want to use a LM4040 as a 2.5V reference for the ADC.
the series resistor is 1k (so polarizing current should be 800uA, 10x of what the LM4040 needs)

Cathode is connected to RA10/Vref+, RA9/Vref- is connected to GND.
Both RA9 and RA10 are configured as INPUTs, both ANALOG.
Vref+ and - selected as references for both ADCs

However, if i take a lm4040 that outputs 2.5V in a test configuration (resistor and reference only, 3.3V supply) and put it in the circuit (same thing, but with a 100n cap to gnd then direct to Vref+ Pin) the voltage output is around 800mV.

The soldering seems to be OK, i can't see or measure shorts to the adjacent pins (Vref- and Avdd)
infact,
resistance between AVDD and Vref+: 1k (the resistor between AVDD and K)
resistance between AVSS and Vref-: 13.8k

do you have any suggestion? some gotcha i'm missing? (i don't know, current inside Vref+ pin is xx mA and that's why is dropping down.. didn's catch anything like that in the datasheet)