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ADALM1000 Calibration Procedure

The ADALM1000 device can be calibrated by the user to achieve more accurate measurements and signal generation. The calibration procedure requires a Digital Multimeter (DMM) and a resistor with a value anywhere between 2.5Ω and 25Ω.

The device is calibrated by taking a set of measurements according to the procedures described in the sections below. The measurement results must be hand written into a calibration file that will be afterwards used by the calibration software to compute all the calibration parameters and write them into the device.

Calibration support is available only stating from Pixelpulse v0.88 and firmware version v2.06 (You don't need to look at the firmware unless you want to - it's only added here for completeness).

Make sure to update the firmware on your device and Pixelpulse before starting the calibration procedure.

Calibration file

The calibration files contains <reference, value> data pairs for all the measurement and source channels. Below is an example of how a default calibration file looks like.

# Channel A, measure V
</>
<0.0000, 0.0000>
<2.5000, 2.5000>
<\>

# Channel A, measure I
</>
<0.0000, 0.0000>
<0.1000, 0.1000>
<-0.1000, -0.1000>
<\>

# Channel A, source V
</>
<0.0000, 0.0000>
<2.5000, 2.5000>
<\>

# Channel A, source I
</>
<0.0000, 0.0000>
<0.1000, 0.1000>
<-0.1000, -0.1000>
<\>

# Channel B, measure V
</>
<0.0000, 0.0000>
<2.5000, 2.5000>
<\>

# Channel B, measure I
</>
<0.0000, 0.0000>
<0.1000, 0.1000>
<-0.1000, -0.1000>
<\>

# Channel B, source V
</>
<0.0000, 0.0000>
<2.5000, 2.5000>
<\>

# Channel B source I
</>
<0.0000, 0.0000>
<0.1000, 0.1000>
<-0.1000, -0.1000>
<\>

The calibration file must contain for each channel at least the data points shown in the example above. It is possible to add as many data points as desired, the only constraint is that the measurement for offset calibration (0V or 0A reference) has to be the first data pair in the data set. A data set for a channel is delimited by the </> and <\> tags. The order of the data sets in the calibration file must be as in the example and the calibration file must contain all the shown data sets otherwise it is not valid.

The example calibration file can be downloaded from the link below. This file assumes perfect device operation - no offset or gain errors, and can be used to reset your device calibration in case an inaccurate calibration file was loaded into the device.

If an inaccurate calibration file was loaded into the device this can be erased by writing into the device the default calibration file.

When you want to re-calibrate your device, before starting the calibration process write into the device the default calibration file and power cycle the device. This will erase the previous calibration and will ensure correct re-calibration.

Storing the calibration data into the device

To store the calibration data into the device:

  • Use the smu binary by typing in a terminal smu --write-calibration /path/to/cal/file (or as smu -w /path/to/cal/file)

The smu binary also supports displaying and resetting calibration for all supported, attached devices via the following:

  • reset: smu --reset-calibration (also as smu -r)
  • display: smu --display-calibration (also as smu -d)

Make sure that Pixelpulse is closed when running the smu binary.

To acquire the smu binary, use the libsmu installer below in addition to installing the correct architecture support for Microsoft's Visual C++ Redistributable for Visual Studio 2015.

libsmu installer: libsmu-setup.exe

If you have multiple ADALM1000 devices make sure that just one device is plugged in when trying to store the calibration data.

Calibration procedures

The procedures below describe all the required steps to perform and record the calibration measurements. The Voltage Source of the ADALM1000 is very precise and normally does not require calibration so it can be left to the default values in the calibration file.

Voltage measurement calibration

Voltage measurement calibration requires at least 2 data points - 0V and 2.5V. The steps below describe the calibration procedure:

  • On the ADALM1000 device connect the CH A and CH B inputs to GND
  • In Pixelpulse set the mode for both channels to Measure Voltage
  • Using Pixelpulse read the voltage measurements for the two channels
  • Replace into the calibration file in the # Channel A/B, measure V sections the <0.0000, 0.0000> data pairs with <0.0000, gnd_value>, where gnd_value is the voltage measurement read in Pixelpulse
  • On the ADALM1000 device connect the CH A and CH B inputs to 2.5V
  • Using Pixelpulse read the voltage measurements for the two channels
  • Using a DMM read the actual value of the 2.5V
  • Replace into the calibration file in the # Channel A/B, measure V sections the <2.5000, 2.5000> data pairs with <dmm_value, pixelpulse_value>, where pixelpulse_value is the voltage measurement read in Pixelpulse and dmm_value is the 2.5V measurement taken with the DMM

Voltage source calibration

Voltage source calibration requires at least 2 data points - 0V and 2.5V. The steps below describe the calibration procedure:

  • In Pixelpulse set the mode for both channels to Source Voltage Measure Current
  • In Pixelpulse make sure that the Repeated Sweep mode is not active
  • From Pixelpuse source 0V on channels A and B
  • Using a DMM measure the voltage outputs of CH A and CH B relative to GND
  • Replace into the calibration file in the # Channel A/B, source V sections the <0.0000, 0.0000> data pairs with <pixelpulse_value, dmm_value>, where pixelpulse_value is the voltage source value in Pixelpulse and dmm_value is the measurement taken with the DMM
  • From Pixelpuse source 2.5V on channels A and B
  • Using a DMM measure the voltage outputs of CH A and CH B relative to GND
  • Replace into the calibration file in the # Channel A/B, source V sections the <2.5000, 2.5000> data pairs with <pixelpulse_value, dmm_value>, where pixelpulse_value is the voltage source value in Pixelpulse and dmm_value is the measurement taken with the DMM

Current measurement calibration

Current measurement calibration requires at least 3 data points - 0A, 100mA and -100mA. Channels A and B must be calibrated sequentially. The steps below describe the calibration procedure:

  • On the ADALM1000 leave both CH A and CH B open
  • In Pixelpulse set the mode of the channel to be calibrated to Source Voltage Measure Current
  • In Pixelpulse read the current measurement for the channel to be calibrated
  • Replace into the calibration file in the # Channel A/B, measure I sections the <0.0000, 0.0000> data pairs with <0.0000, gnd_value>, where gnd_value is the current measurement read in Pixelpulse
  • On the ADALM1000 device connect the CH A or CH B to one end of the resistor
  • Connect the other end of the resistor to the current input of a DMM
  • Connect the GND of the DMM to the ADALM1000 2.5V pin
  • In Pixelpulse source a voltage value on the channel to be calibrated so that the current measurement is close to 100mA
  • In Pixelpulse read the current measurement for the channel to be calibrated
  • Read the current measurement on the DMM
  • Replace into the calibration file in the # Channel A/B, measure I sections the <0.1000, 0.1000> data pairs with <dmm_value, pixelpulse_value>, where pixelpulse_value is the current measurement read in Pixelpulse and dmm_value is the current measurement taken with the DMM
  • In Pixelpulse source a voltage value on the channel to be calibrated so that the current measurement is close to -100mA
  • In Pixelpulse read the current measurement for the channel to be calibrated
  • Read the current measurement on the DMM
  • Replace into the calibration file in the # Channel A/B, measure I sections the < -0.1000, -0.1000> data pairs with <dmm_value, pixelpulse_value>, where pixelpulse_value is the current measurement read in Pixelpulse and dmm_value is the current measurement taken with the DMM

Current source calibration

Current source calibration requires at least 3 data points - 0A, 100mA and -100mA. Channels A and B must be calibrated sequentially. The steps below describe the calibration procedure:

  • On the ADALM1000 device connect the CH A or CH B to one end of the resistor
  • Connect the other end of the resistor to the current input of a DMM
  • Connect the GND of the DMM to the ADALM1000 2.5V pin
  • In Pixelpulse set the mode of the channel to be calibrated to Source Current Measure Voltage
  • In Pixelpulse source 0A on the channel to be calibrated
  • Read the current measurement on the DMM
  • Replace into the calibration file in the # Channel A/B, source I sections the <0.0000, 0.0000> data pairs with <pixelpulse_value, dmm_value>, where pixelpulse_value is the current source value in Pixelpulse and dmm_value is the measurement taken with the DMM
  • In Pixelpulse source 100mA on the channel to be calibrated
  • Read the current measurement on the DMM
  • Replace into the calibration file in the # Channel A/B, source I sections the <0.1000, 0.1000> data pairs with <pixelpulse_value, dmm_value>, where pixelpulse_value is the current source value in Pixelpulse and dmm_value is the measurement taken with the DMM
  • In Pixelpulse source -100mA on the channel to be calibrated
  • Read the current measurement on the DMM
  • Replace into the calibration file in the # Channel A/B, source I sections the < -0.1000, -0.1000> data pairs with <pixelpulse_value, dmm_value>, where pixelpulse_value is the current source value in Pixelpulse and dmm_value is the measurement taken with the DMM

Semi-automated Procedure

The ALICE 1.1 DeskTop Software includes a semi-automated method to calibrate the ADALM1000 using the AD584 precision 2.5 V reference from the ADALP2000 Analog Parts Kit. Just wire up an AD584 for a 2.5 V output, powered from the fixed 5V supply from the ALM1000 and follow the steps as outlined in the ALICE desktop user's guide. No DMM needed (except to maybe verify the output of the AD584).

/srv/wiki.analog.com/data/pages/university/tools/m1k/calibration.txt · Last modified: 19 Mar 2017 17:16 by lemoneer