TI Evaluation Module for ADS127L01 Delta-Sigma ADC - Review

Table of contents

RoadTest: TI Evaluation Module for ADS127L01 Delta-Sigma ADC

Author: s2000gt

Creation date:

Evaluation Type: Evaluation Boards

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?:

What were the biggest problems encountered?: Application software at very early stage of development, very few analysis options available.

Detailed Review:

Overview:

 

The ADS127L01EVM is an evaluation module that provides hardware and software support for evaluation

of the ADS127L01 delta-sigma ADC. The EVM utilizes the TM4C1294NCPDT processor to communicate

with the ADC via SPI and provide communication with a PC over USB interface. The EVM also includes a

software application that runs on a PC to allow for register manipulation and data collection from the ADC.

 

 

Hardware:

 

The EVM is powered via the USB interface with the PC.

 

 

The EVM comes configured with the following hardware settings.

 

Inputs:

 

Analog input signals can be connected through the SMA connectors (J7 and J9) or through the terminal

block (J8).

By default, the EVM is configured for a fully-differential analog input signal.

 

 

Access the digital signals of the device via the debug header (J6). This header allows for the connection

to a logic analyzer or to another processor when the Tiva microcontroller is not used.

 

 

Other Hardware sections:

 

The onboard oscillator, Y2, provides a 16-MHz, low-jitter clock for the ADS127L01.

 

 

The ADS127L01 uses hardware mode pins to select the operating mode, interface mode, digital filter

response, and oversampling ratio (OSR).

 

 

The reference voltage on the ADS127L01 is the voltage difference between REFP and REFN. REFN is

tied directly to AGND.

 

 

Software:

 

Download the DELTASIGMAEVAL-GUI-installer.exe installer and the ADS127L01-devpkg.exe from the ADS127L01EVM tool page and

save to a known folder. Run the installers and follow the on-screen prompts.

Note: I had some issues with the device drivers being automatically loaded by Windows 7, this required manual driver loading in device properties.

 

After the Delta-Sigma ADC EvaluaTIon Software and the ADS127L01 device package are installed,

ensure that all jumpers and switches are in their default positions and then connect the

hardware with the provided USB mini cable. Start the Delta-Sigma ADC Evaluation Software. The GUI

automatically detects the connected hardware and displays the device register map under the Main tab.

 

 

 

The EVM software provides an alternate way to configure the ADS127L01 hardware mode pins when

JP11 is uninstalled. These controls can be found underneath the Register Controls on the Device tab.

 

 

Data is collected by clicking the Data Analysis button from the ribbon menu. This will launch the Analysis

Engine in a separate window. The Analysis Engine is used to collect, analyze, and save data from the

EVM.

 

Data Inspector

 

Time Domain

 

Histogram

 

No other analysis options are available at the current software status, the software does however

allow the export of data to the legacy application HSDC Pro format, which does have more advanced

analysis tools.

 

 

There is also a console window option enabled in settings, for manual control and scripting.

 

 

Test Inputs:

 

50hz

 

2.5khz

 

Conclusion:

 

The ADS127L01 24-bit, delta-sigma (ΔΣ), analog to digital converter (ADC) is a very versatile chip. I look forward to working more

with this EVM in the future, but the software definitely needs to mature more with at least a good FFT analysis option.

Anonymous
  • Nice start, but what are your plans to look at the full range of this device.

     

    Could you elaborate on the low scores, identify what you felt was missing and what you would like to see in the software?

     

    What are your plans for testing the full 24-bit range?  Do you have a signal source over which you can compare the board against?

     

    DAB