Is there any digital DDC thip or ADC chip with Integrated DDC for 200K-400Khz using

Hi Cun,

I am not sure I completely follow your question. Just to make sure because I know the naming can be confusing, DDCxxx, like DDC2256A, are photodiode front-end products frequently used in the Computed Tomography space (CT), not the classical digital down converters for communications. If you are looking for communications IC, you probably have to check a different forum...

Anyhow, if you are looking for "CT" DDC, these are current input to digital output. They have an integrator and ADC for every channel. The fastest is the DDC316 that can do 100KSPS with 12b. Bandwidth is a bit more tricky to define. Some DDCs can take pulses faster than what the sample rate would indicate but before we go into that level of details please confirm you are referring to these products.

If you are looking for something that can digitize a current at 200-400KSPS, DDCs can't do that. You will need a discrete transimpedance amplifier and ADC.

Regards,

Edu

Cun:

Within the High Speed Data Converter portfolio there are several ADC options that include integrated DDC.  In the original post you stated a desire to operate at 200 - 400 kHz.  I presume that you mean 200-400 kSPS data rate.  This is a low speed data rate and generally is accomplished with a straight ADC not employing digital down conversion.  DDC operation usually is used when the sample rate is large yet the data rate must be kept at more reasonable speeds.  The afore referenced link to RF sampling data converters falls into that category where the sampling rate is in GSPS and the data rate is in the MSPS range.

The proper device is dependent on the output sampling rate required.  I presume that you are looking for something with a few MSPS sampling rate that can be down converted to a few hundred kHz data rate.  There are no offerings on the market within high speed converters that offer that type of configuration.  You can check out a device like the ADC3221 which is a 25 MSPS low power ADC. 

--RJH

Cancellation parameters are bound by [0,1], a unit circle.  The “0” represents complete cancellation and the “1” represents no cancellation.   In dB-scale, the function is bound by [-inf,0]. The two orthogonal input variables, [x,y], represent a two-dimensional space.  The parameter magnitude is determined by the input variables deviation from the ideal point, [x0,y0].  Figure 1 illustrates a circle that represents the infinite possibilities x,y points that yield a magnitude, r.

Cun:

Ah, OK.  You are looking for an output sampling rate of ~200 kHz that can be digitally down-converted to ~100 kHz or less.  Edu may have a better portfolio of high cannel count devices with very low sampling rates that would be a good fit for your application.  I will defer to his expertise on those devices.

My team operates with higher sampling rates in the tens of MSPS to GSPS.  There is a new device in development that could support the very low data rate.  This device is a 14-bit dual ADC.  It includes up to 32x decimation.  You could operate with a 100 kHz data rate corresponding to a 3.2 MSPS output sampling rate or with smaller decimations, you could operate with lower sampling rate.  I am not sure how low you can go.  Something like 1 MSPS seems reasonable.

I cannot discuss this device with much detail on a public forum.  If it sounds interesting, please contact your local TI sales representative and they can assist in getting you more details. 

Hello,

We don't seem to have any single IC solutions for your high-channel count DDC type application. We do offer many higher channel count ICs which can meet that sampling rate, such as the ADS8168.  Many of these IC's could be combined together to meet the application needs.