I am in selection process.As you know automotive application is cost sensitive especially in India. I need to detect vibration,shock,sudden accleration and tri axial accleration. My application is automotive diagnostic,telematics and measurement,ECU related etc.4 Bridge Sensors then MUX(4:1 x2) and instru AMP and a ADC. The AD7683 doesn't have the capability to generate interrupt or BUSY signal. Usually there are two types of clocks in our SAR ADCs -one internally generated for the conversion and one applied externally to read back the data -both of them run asynchronously. The internal clock mentioned in the datasheet is not an error. I wouldn't worry about the jitter here as this is a low-speed application.
#DCLOCK 8088 SERIAL#
Let me clarify that you can control the sample rate with CS and then serial clock has an effect of that in terms of conversion time.Īs I said before DCLOCK is an input of the AD7683, so you will have to provide an external clock. Keep in mind that a minimum of 22-clock cycles are required for AD7683 16-bit conversion and DOUT goes low on the DCLOCK falling edge following the LSB reading. It also has a BUSY signal indicator to interrupt the digital host and trigger the data reading. It has two modes - CS mode and chain mode. I think Tim has already addressed some your concerns.įirst off, I'd recommend you to use the AD7685 for your application, which is a higher speed -250KSPS part with more functionality at the same price. Pls comment in the point of contiuous reading of the ADC ,probably with a seperate crystal. Usually the SPI clock is just for reading the Sampled data.It can be of any value and periodically DSP will read it by giving a high clock data quickly so that it can use the SPI bus for other ADCs or devices.Sampling is done by an internal or external clock with or without PLLs,results are just made ready in the SPI buffer to read. Usually it is some down conversion of DCLOCK can sample this.ġ.It means that Micro Controller's SPI will be continuously busy by giving the clock at desired sampling rate.Ģ.We can not put anything else on that SPI as the clock will be too slowģ.Aperture Jitter will be there as the sampling clock is derived from DCLOCK.Ĥ.What is the use of internal clock mentioned at the start of the Datasheet.ĥ.Is there any EOC ?to interrupt the DSP?
Is this correct?I mean DCLOCK can go in MHz (1.2MHz) how it will work then? What I understood from you is DCLOCK is the one which decides the sampling. What it means is that I can not sample the ADC continuously !
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