请教一个关于2837x系列的ADC的参考电压的供电问题
资料上是这样说的
基本就是说每个ADC模块都用一个放大器来供电,也可以两个共用一个放大器,但是要满足手册上的要求。
我的问题:
1,共用放大器时的要求是什么?从data manual中没太看明白
2,如果ADC A,B,C,D四个模块共用一个放大器供电,会有什么影响?
谢谢!
JIE ZHANG:图片没粘贴上,补发一下;
Figure 10-22 shows the basic organization of the external voltage reference generation circuitry. A single
reference voltage generation should be shared by all ADC modules. This will minimize reference voltage
mismatch between ADC modules. The reference voltage should then be buffered by a precision op-amp
with good bandwidth and low output impedance before being driven into the reference pin. A capacitor
between the high and low reference pins should be placed on the PCB as close to the pins as practical to
help absorb high frequency currents. A series resistor (typically <1Ω ) in series with this capacitor may be
necessary to ensure op-amp
It is also possible to share two reference pins between one op-amp driver. This organization is shown in
Figure 10-24. This will give slightly reduced performance compared to the case where each reference pin
has a dedicated op-amp buffer, but it should still be possible to achieve all ADC specifications in the data
manual..
请教一个关于2837x系列的ADC的参考电压的供电问题
资料上是这样说的
基本就是说每个ADC模块都用一个放大器来供电,也可以两个共用一个放大器,但是要满足手册上的要求。
我的问题:
1,共用放大器时的要求是什么?从data manual中没太看明白
2,如果ADC A,B,C,D四个模块共用一个放大器供电,会有什么影响?
谢谢!
Annie Liu:
回复 JIE ZHANG:
为更加有效地解决您的问题,我们建议您将问题发布在E2E英文技术论坛上“http://e2e.ti.com/support/microcontrollers/c2000/f/171”,将由资深的工程师为您提供帮助。我们的E2E英文社区有TI专家进行回复,并得到全球各地工程师的支持,分享他们的知识和经验。