最近用AD7918 和 ARM9 (linux平台)通信,通过SPI 接口,如下SPI写 0x93,0x30 配置寄存器选择AD转换的通道。但是通过read 函数读回来的数据并不是 对应通道的数据。(数据像是随机的)
问题1 . 再写控制寄存器时,DOUT 上输出的是什么数据? 如下图 黄色 输入配置,蓝色DOUT输出。
问题2. 输出的后端波形异常。上升沿很缓慢,电路上已经上拉到3.3V 。怎么会出现这个情况?
麻烦知道朋友指导,谢谢!
您好!
不能正常读到数据请先检查硬件设计,看硬件设计是否正确,硬件设计请参考附件内AD7928评估板原理图。确保硬件设计正确后,请检查焊接是否正常,通常虚焊或短路会导致芯片状态不正常。
对于软件部分的检查,首先应保证初始化流程与数据手册中流程要求一致。在数字读写时,则应保证读写时序遵守数据手册中时序图。
Hi Tarzan,
The AD7918 device can be operated with 2.5 V +/-1% reference only. Such restriction is driven by the internal comparator in the part which starts to operate outisde its normal operating region when the reference is not withing datasheet limits…
Hi Kevin,
I have attached some list of ADC that were Automotive Qualified. Do you have specific paramater that you are looking for an ADC? like Throughput rate, no. of channels, or Resolution.
You can also visit the Analog Devices website and filter…
AD693 |
AD5410 |
AD5412 |
AD5420 |
AD5422 |
AD5735 |
AD5755 |
AD5755-1 |
AD5737 |
AD5757 |
AD5421 |
AD421 |
AD5758 |
AD7569 |
AD7669 |
AD7868 |
AD7869 |
AD5593R |
AD5592R |
AD5940 |
AD5941 |
AD7293 |
AD7294-2 |
AD7292 |
AD5590 |
AD7294 |
L… |