Question about ADC and DAC

[hoangthanhtung]

fpga dac

Say that can implemetion ADC or DAV with FPGA or CPLD by VHDL. It is right or wrong ? If it is right, anyone give me some link, documents or source code about this problem. I am using FPGA and CPLD chip of Xilinx and use ISE 6.1

Thank so much. Bye

 

[cube007]

fpga adc dac

Hello hoangthanhtung,

ADCs and DACs can’t be implemented in FPGAs or CPLDs. FPGAs and CPLDs are only for digital logic. You have to choose your desired DAC and ADC from companies like Analog Device, Maxim, TI, … and connect this one to the FPGA or CPLD.

Bye,
cube007

 

[mc&fpga]

fpga dac

ithink you can find in atmel component,but xilinx componets don't have
adc and dac
atmel have a 94sXX series that consist of fpga and avr microcontroller with adc.

 

[hover]

dac fpga

You can write a virtual ADC or DAC by HDL language. (It cannot be synthesised, just for simulating.) You can write it according to some existing ADC or DAC chip reference. It is very helpful if you want to verify your design such as DDS or chip core(like ARM).

 

[weilijun]

adc vhdl

It seems that Altera may provide IP core for ADC and DAC. Maybe you can check it on Altera's web.

 

[dll_embed]

xilinx application notes dac

Actually, it is possible to implement synthesizable ADC/DAC inside FPGA with very few analog devices added. Xilinx has examples on using sigma-delta algorithm to implement them. Take a look at below link for their app.

https://www.xilinx.com/bvdocs/appnotes/xapp154.pdf


It is quite interesting.

regards.

 

[ME]

dac with fpga

You can implement an DAC in FPGA by connecting external resistors as an R/2R ladder + a buffer. You can decide how many bits you want, just add another branch to the ladder to increase the resoloution.

You can actually buy R/2R ladder networks as an IC.
Here's some R/2R ladder networks:
**broken link removed**
https://www.bourns.com/2/pdfs/2qsp2nbsxx6.pdf
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This could be connected to the FPGA outputs pins and put a buffer to the output of the ladder.
But the hi voltages and lo voltages of the FPGA needs to be stable if you need a precise DAC.

 

[ME]

xapp154

Lattice also makes some mixed-signal CPLDs called ispPAC (in-system programmable analog ICs):
http://www.latticesemi.com/products/ispPAC/index.cfm'

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[alphi]

fpga dac adc

general fpga have not implement dac or adc,some special fpga integrate dac or adc unit,so it can use it.

 

[mc&fpga]

xapp154.pdf

Hello hoangthanhtung,

ADCs and DACs can’t be implemented in FPGAs or CPLDs. FPGAs and CPLDs are only for digital logic. You have to choose your desired DAC and ADC from companies like Analog Device, Maxim, TI, … and connect this one to the FPGA or CPLD.

Bye,
cube007

can you explain more and any tutorial how we can simulate adc |dac in fpga,it means there are testbench of the adc|dac for checking them,and can modelsim do that or we need other software?

 

[cube007]

implement adc in fpga+tips

Hello hoangthanhtung,

ADCs and DACs can’t be implemented in FPGAs or CPLDs. FPGAs and CPLDs are only for digital logic. You have to choose your desired DAC and ADC from companies like Analog Device, Maxim, TI, … and connect this one to the FPGA or CPLD.

Bye,
cube007

can you explain more and any tutorial how we can simulate adc |dac in fpga,it means there are testbench of the adc|dac for checking them,and can modelsim do that or we need other software?

Helllo mc&fpga,

I didn’t mean that you can integrate a DAC or ADC in the FPGA like an IP-Core. The best is to bye a specific ADC or DAC (which meats your requirements) from known companies and connect this Chip by wires with the FPGA. There are a lot of ADCs and DACs on the market. First you have to set your boundary conditions like Voltage or Current Input/Output, resolution, sample speed, etc. After this you can write an interface in VHDL/Verilog to communicate with the outside device. I don’t know if there are simulations models for these devices. But you can write your own testbench which simulates the ADC/DAC outside of your FPGA.

Bye,
cube007

 

[mc&fpga]

fpga daq

I didn’t mean that you can integrate a DAC or ADC in the FPGA like an IP-Core.
cube007[/quote]
ya i understand your mean,that we can model the adc /dac with verilog or vhdl component in comany site that make adc..
so which software did you use for simulation the adc in fpga.
did you ever use those components.

 

[jay_ec_engg]

adc dac tutorial + pdf

HI synthesizable DAC is possible but ADC is not synthsizabel...
u can use VHDL AMS for that....
u can check xilinx application notes.. for ADC and DAC codes....
jay


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sysnthesizable DAC .. unipolar....
Virtex Synthesizable Delta-Sigma DAC
**broken link removed**

ADC vhdl code .. but not synthesisable....unipolar
Virtex Analog to Digital Converter
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