Hi,
Below is an example about SAR ADC driver design,I want to know how to get this formula and why should the time constant (τ = RF×CF) be equal or less than {tAQ/[(N+1)*ln2]}?
Thanks！
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Ask questions about SAR ADC Driver
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ADS1299EEGFE-PDK: Can the software of ADS1299EEGFE-PDK display signal waveforms continuously and in real time?
Part Number: ADS1299EEGFE-PDK
When using the software of ADS1299EEGFE-PDK to acquire signal, can it display signal waveforms continuously and in real time?
I used it to acquire the signal and found that it can only update the waveform discontinuously based on “Samples/CH”. Is it right?
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DAC34H84EVM: clock generator clok not stable & info about external clock
Part Number: DAC34H84EVM
Hi,
I am configuring DAC34H84 EVM with CDCE62005 as a DACCLK source.
1. My question is that whenever I configure CDCE62005 through GUI software, it seems to be it is not getting stored in ROM, whenever the board is powered up, the previous configuration is lost. I have also tried configuring with EEPROM locked/unlocked option but no luck. Is there a way to keep the configuration save so that I don't have to do it again every time the board is powered up.
2. With the default configuration, The output frequency of CDCE62005 (DACCLK/DACCLKC) is not stable it gives sometimes 150MHz, sometimes 140Mhz, 130MHz, and it keeps on changing because of which I am getting a lot of noise in the DAC output. Is it normal?
3. Can I use external clock as a DACCLK source through bypassing the CDC clock generator IC. From schematics I found two connectors J22 and J23 for external clock on the EVM board. Also on the board R124 and R125 are not installed, should I install them and use external clock? Also on R124 and R125 DNI(Do not install) is written, If R124 and R125 is not supposed to be installed, should I bypass them otherwise what's the reason of including them?
4. In case of external clock what should be the amplitude (voltage peak to peak) and what should be the value of R124 and R125?
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DAC38RF85: power consumption as single tone DDS?
Part Number: DAC38RF85
What is the power consumption for the DAC38RF85 if used only in NCO mode (as a single tone DDS), no baseband inputs, and with an external CLK source?
Also, does the the power consumption vary with CLK rate? Such as 4, 5, 6 GHz?
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TSW1400EVM: TSW1400EVM 8 channel analysis
Part Number: TSW1400EVM
Hello,
Manual for TSW1400EVM says:
- Analysis on up to eight simultaneous channels
What is meant by these eight channels? Does that mean, this board can capture simultaneously 8 analog input channels only? I want to use ADS52j90EVM with TSW1400EVM and capture 16 or 32 channels simulatenously. Simultaenous capture is very crucial for me.
And second one, is this true with these boards:
- 8 channels, 10 bits resolution, speed 200 MSPS
- 16 channels, 14-10 bits resolution, speed 100 MSPS
- 32 channels, 10 bits resolution, speed 100 MSPS
Or can I somehow make 32 channels with 100 MSPS with TSW1400EVM and ADS52j90EVM?
Thanks,
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AFE5832: How to buy Swaroop board
Part Number: AFE5832
Customer want to use AFE5832 in their product and get the a User_guide from TI.
It seems like they must design by Swaroop board.
What is Swaroop board? How to buy it?
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AFE4300: AFE4300
Part Number: AFE4300
I am using AFE4300-EVM, referring document "Impedance Measurement with AFE4300" provided by TI. I tried to measure RC series circuit (R=659, C=100nF). The resulted Magnitude value is somewhat ok but the phase result is of the opposite sign as seen in the image. I also tried datasheet section 8.1.3 "Achieving Deterministic Phase in the IQ Mode" but got no luck. I saw some previous threads about the same problem and want to know if there is any solution.
afraiz
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ADS5400: Differences between revision B and revision C of the ADS5400
Part Number: ADS5400
The ADS5400 datasheet shows change from B to C, but it's too abstract. Is there any change detail
I found that the Rev.C works, while the Rev.B doesn't
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LMP92001: Design with 12 I/O's
Part Number: LMP92001
I am interested in your A/D, D/A ICs and have started to look at the different options that I have !
Currently I reviewed the TI LMP92001 and have a couple of questions :-
1. Is correct that this chip has a A/D sample rate of approx. 300 kHz (kSPS) - since its hold time is 3.3uS ?
2. In my design I have 12 IOs - I am interested in creating as flexible design as possible. Thus is it possible with this chip to configure (Selectable) the I\Os as either 12 channel A\D, 12 channel D\A OR 12 Channel GPIOs ? If yes what type of additional circuitry would I require ?
3, If I need a higher A/D sample rate - what type of solution would you suggest to enable to achieve the design requirement in 2. above ?
Thanks in advanced
Shmuel
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TLA2022: TLA2021, TLA2024 I2C
Part Number: TLA2022
Dear *,
Can we connect the I2C of TLA202x to 1.8V with pull-up?
Our system i2C is 1.8V, and we would like to avoid the level translator.
if no what low-cost ADC solution do you suggest that has 1.8V I2C communication?
Best Regards,
D.
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AFE5809: Observed Non-Linearity at the input of AFE5809 ADC.
Part Number: AFE5809
Hi All,
We are using AFE5809 in one of our project. Here we are giving AC coupled (1uF) ADC input range from 1KHz to 15MHz.
We have designed the internal High Pass Filter of AFE5809 ADC with the Cut-Off frequency of 100KHz by connecting a 15nF capacitor from INM pin to Ground.
We have set the register configuration as shown below:
Address - Data in (HexaDecimal)
16 0001
04 0008
03 2000
02 2000
Hereby attaching all the waveform observed before and after the AC coupling capacitor and also attaching the schematic for your reference. Also attaching the ADC outputs plotted waveform in MatLab.
Can you please advice on the above issues.
(Please visit the site to view this file)
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ADS124S06: Error in measured value and actual value of resistance.
Part Number: ADS124S06
Hello,
We are using the ADS124S06 ADC in our circuit for measuring resistance value with the following settings:
PGA= enabled
Gain= 1
Global chop= OFF
Filter setting: Low Latency filter
Below circuit is used to measure the value of R2. Both the R1 and R2 resistors are high precision resistors (TCR of 2ppm). Formula used to calculate the values is also shown below. R2 value is measured with respect to ADC internal 2.5V reference using ratiometric measurement.
During measurement we have observed that there is a difference between resistance value measured using a high accuracy resistance meter and the one obtained from the ADC.
We have taken the observation for three different values of R2= 2K, 10K and 33k ohms and got different values of resistances. R1 was a high precision resistor, its value is 10000.5 Ohms. Moreover, the counts variation also differ from one resistance value to other. Below are the observations for the same.
As can be seen that measurement of R2 has certain error which varies from 1 to 4 ohms depending on resistance to be measured. It is a drift as the value measured is stable to 20 ADC count variations. Could you please suggest the possible source(s) of error which is coming between the actual and the measured resistance values? also please suggest any changes needed to reduce this error as we want to use it for precision measurement application.
Please note that the supply to ADC is given through a low noise High PSRR TPS7A49 LDO and doesn't have any switching supply.
Regards
Tushar Bhavsar
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ADS112C04: ads112c04 registers configuration problem
Part Number: ADS112C04
Hi!
Part A:
When I use ADS112C04, I met some problems.
1 Configure 4 registers(Reg0~Reg3) through I2C
write Reg0:0x3A //
write Reg1:0xA0 //
write Reg2:0xA0 //
write Reg3:0x24 //
2 All 4 registers read and write normally in first time. then I read the register again, it's failure that the value is different with the first time and the AD samples is wrong.
you can see the figures as follow, please help to analyze.
Part B:
As described above. I have another problem. Do you have the recommended configuration? And is the configuration order required ?
BRs,
Barret
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ADS1018-Q1: ADS1018-Q1
Part Number: ADS1018-Q1
Hi
i am using ads 1018 adc on mpc5777xc controller, i unable to get adc data , just getting 255 value, please tell me about DRDY pin , is it require to monitor or not , and how many times need to send data to config reg
thanks
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ADS54J64EVM: evaluate mode 6
Part Number: ADS54J64EVM
Hello
The mode 6 (IQ 125MSPS) is not supported in HSDC pro software. We would like to try it in our carrier board with FMC connector.
Is still possible set the mode 6 with ADS58J64 EVM GUI (JP3 set to USB mode)?
We would like to bypass CPLD with JP3 set to FMC mode.
What is funcionality of CPLD in this configuration?
What is purpose of signals FMC_D5, FMC_D6 and FMC_DIR_CONTROL?
Thanks and Regards
Daniel
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DAC REQUIRED FOR GENERATING 26MHZ CLK
Hello Team
we are looking for DAC which is capable of generating 26MHz clk with the following parameters
Reference voltage: 1.8v
Rise/Fall time: Not more than 5ns
Duty cycle 50%
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ADS1278: ADS1278 : SPI Data Read
Part Number: ADS1278
Greetings,
I am using ADS1278 EVM with Dspic33 with these specifications:
- Fclk = 27 MHZ (onboard)
- mode : Low speed
- Format: SPI - TDM - Dynamic
- Only 1 channel enabled rest is PWDN
the issue that i am reading by detecting the DRDY low signal then read the SPI data and the result is fine but when i slow the sampling time (in DSPIC software by using timer), noticed that the analog doesn't change instantly and i have to read a lot of data to reach the correct analog value
so how to solve this issue, i tried using PWDIN after reading but result is the same.
Also i am checking on DRDY without interrupt only in timer, is this correct ?
if (ADS1278_DRDY == 0)
{
uint32_t temp;
WriteSPI2(NOP);
while(SPI2STATbits.SPIRBF == 0);
temp = ReadSPI2();
WriteSPI2(NOP);
*data = (uint32_t)(temp << 16);
while(SPI2STATbits.SPIRBF == 0);
temp = ReadSPI2();
WriteSPI2(NOP);
*data |= (uint32_t)(temp << 8);
while(SPI2STATbits.SPIRBF == 0);
temp = ReadSPI2();
*data |= (uint32_t)temp;
//here i disabled the channel using PWDIN
}Thanks
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ADC12D1620QML-SP: Will driving the input clock continuously when powered off damage the ADC
Part Number: ADC12D1620QML-SP
Will driving the input clock continuously when the ADC is powered down damage the chip?
I understand having a clock driving those pins will charge the diode's without the rest of the chip powered up but is that harmful to the chip overtime?
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ADS124S08EVM: Data collection problem in ADS124S08 EVM
Part Number: ADS124S08EVM
Hello sir,
When I am connecting my voltage source at J9 jumper(AIN10(+) and AINCOM(-)), evaluating with ADS124S08 EVM and running the predefined script that is voltage measurement,then I opened the data analysis tool and I pressed the Collect button then no data was coming and D3 LED was still red,D2 LED also didn't flashed once.
But when I am not selecting any script and simply giving COLLECT (Number of points) from Console then D2 LED flashed once and some random data came in data analysis tool.
Please suggest the possible answer to the problem.
Thanks.
Regards
Sushmita Chaudhary
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DAC38J84EVM: BRD file
Part Number: DAC38J84EVM
The DAC38J84EVM Design Packet came without a BRD file (other TI boards I've used included a BRD file in the design packet). Does the file not exist for this particular board or is there some other way to access it?
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