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Entry  Tue Jun 25 19:18:07 2013, gautam, Configuration, endtable upgrade, plan of action for PZT installation 
    Reply  Wed Jul 3 21:19:04 2013, gautam, Configuration, endtable upgrade, plan of action for PZT installation DAC_bank.pngASC_schematic.pdf
       Reply  Mon Jul 8 13:45:19 2013, gautam, Configuration, endtable upgrade, Driver board verification 
          Reply  Wed Jul 10 22:41:06 2013, gautam, Configuration, endtable upgrade, PZT Driver Board HV_Amplifier.pdf
             Reply  Thu Jul 11 23:50:57 2013, gautam, Configuration, , PZT Driver Board-changes made ASC_schematic.pdfDAC_Max_output.JPG
                Reply  Mon Jul 15 11:51:18 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4-Max Output and Power Spectrum max_amp.JPGmax_amp_all_channels.JPGDACOffPowerSpec.pdfDACOnPowerSpec.pdfDAC2kPowerSpectrum.pdf
                   Reply  Mon Jul 15 13:51:17 2013, Koji, Configuration, endtable upgrade, DAC at 1Y4-Max Output and Power Spectrum 
                      Reply  Mon Jul 15 15:54:20 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -with the right units DACOffPSD.pdfDAC500PSD.pdfDAC2000PSD.pdf
                         Reply  Mon Jul 15 17:20:43 2013, Jenne, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -with the right units 
                            Reply  Mon Jul 15 17:59:31 2013, gautam, Configuration, endtable upgrade, DAC at 1Y4- Power Spectrum -6.4kHz bandwidth DAC-6.4_kHz_BW_PSD.pdf
                               Reply  Tue Jul 16 14:51:09 2013, gautam, Configuration, endtable upgrade, AI Board-D000186-Modified notches D000186_Frequency_Response.pdf
                                  Reply  Thu Jul 18 19:09:08 2013, gautam, Configuration, endtable upgrade, QPD Calibration for PZT Calibration QPD-XCalib.pdfQPD-YCalib.pdfError_Function_Fitting.zip
                                     Reply  Thu Jul 18 20:20:52 2013, gautam, Configuration, endtable upgrade, First mirror glued to PZT and mounted in modified mounts Piezo-mirror.jpg
                                        Reply  Thu Jul 18 23:34:40 2013, gautam, Configuration, endtable upgrade, Coarse adjustment of PZT axes orientation in mount PZT_out_waveform.jpg
                                           Reply  Fri Jul 19 23:35:31 2013, gautam, Configuration, endtable upgrade, Preliminary Calibration of PZT QPD-XCalib.pdfQPD-YCalib.pdfPiezo_Yaw_Calib-in_QPD_linear_range-Pitch_tilt.pdfPiezo_Yaw_Calib-in_QPD_linear_range-Yaw_tilt.pdf
                                              Reply  Tue Jul 23 20:41:40 2013, gautam, Configuration, endtable upgrade, Full range calibration and installation of PZT-mounted mirrors M1_Pitch_calib.pdfM1_Yaw_calib.pdfM2_Pitch_calib.pdfM2_Yaw_calib.pdfPI_S330.20L.pdf
                                                 Reply  Mon Aug 5 18:48:44 2013, gautam, Configuration, endtable upgrade, Full range calibration of PZT mounted mirrors for Y-endtable 2-inch-CVI-Yawcalib.pdf2-inch-CVI-Pitchcalib.pdf1-inch-Laseroptik-Yawcalib.pdf1-inch-Laseroptik-Pitchcalib.pdf
                                        Reply  Fri Jul 19 22:51:40 2013, gautam, Configuration, endtable upgrade, Second mirror glued to PZT and mounted  Piezo-mirror_2.JPG
                                           Reply  Tue Jul 30 19:44:05 2013, gautam, Configuration, endtable upgrade, Second mirror glued to PZT and mounted  
                                  Reply  Thu Jul 18 21:12:58 2013, gautam, Configuration, endtable upgrade, AI Board-D000186-All channels modified AI_Board_Output.jpg
                Reply  Mon Jul 29 13:39:25 2013, gautam, Configuration, endtable upgrade, PZT Driver Board-further changes D980323-C-modified.pdfD980323-C-modified-pg2.pdf
          Reply  Mon Jul 29 21:57:45 2013, gautam, Configuration, endtable upgrade, Hardware installed at 1X9 
             Reply  Tue Jul 30 19:40:47 2013, gautam, Configuration, endtable upgrade, DAC-PZT Driver Board Output Signal Chain Tested 
Message ID: 8845     Entry time: Mon Jul 15 11:51:18 2013     In reply to: 8832     Reply to this: 8846
Author: gautam 
Type: Configuration 
Category: endtable upgrade 
Subject: DAC at 1Y4-Max Output and Power Spectrum 

 Summary:

I measured the maximum output of the DAC at 1Y4 as well as its power spectrum. The results are as follows (plots below):

  • Maximum amplitude of differential output: + 10V.
  • Power spectrum has a peak at 64 kHz.

Therefore, the gain of the high-voltage amplification stage on the PZT driver boards do not need to be changed again, as the required output range of 0-100V from the DAC board was realised when the input voltage ranged from -10V to +10 V w.r.t ground. The AI board converts the differential input to a single ended output as required by the driver board.

I will now change some resistors/capacitors on the AI board such that the position of the notches can be moved from 16k and 32k to 64k and 128k.

Procedure:

 Max. amplitude measurement

My previous measurement of the maximum output amplitude of the DAC was flawed as I made the measurement using a single channel of the oscilloscope, which meant that the negative pin of the DAC channel under test was driven to ground. I redid the measurement to avoid this problem. The set up this time was as follows:

  • Positive pin of DAC connected to channel 1 of oscilloscope using break out cable and mini-grabber probe
  • Negative pin of DAC connected to channel 2 of oscilloscope
  • Grounds of channels 1 and 2 connected (I just hooked the mini-grabbers together)
  • Measurement mode on oscilloscope set to channel 1 - channel2
  • Used excitation points set up earlier to output a 3 Hz sine wave with amplitude of 32000 counts from channel 9 of the DAC. 

The trace on the oscilloscope is shown below;

max_amp.JPG

So with reference to ground, the DAC is capable of supplying voltages in the range [-10V 10V]. This next image shows all three traces: positive and negative pins of DAC w.r.t ground, and the difference between the two.

max_amp_all_channels.JPG

 Power spectrum measurement

 

I used the SR785 to make the measurement. The set up was as follows:

  • Positive pin of DAC to A-input of SR560
  • Negative pin of DAC to B-input of SR560
  • A-B output to Channel 1 input A of the SR785
  • SR785 configured to power spectrum measurement

Initially, I output no signal to the DAC, and obtained the following power spectrum. The peak at 65.554 kHz is marked.

DACOffPowerSpec.pdf

I then re-did the measurement with a 200 Hz (left) and 2000 Hz(right), 1000 counts amplitude (I had to change the Ch1 input range on the SR785 from -18dBm to -6dBm) sine wave from channel 9 of the DAC, and obtained the following. The peaks at ~64 kHz are marked.

DACOnPowerSpec.pdf    DAC2kPowerSpectrum.pdf

Now that this peak has been verified, I will work on switching out the appropriate resistors/capacitors on the AI board to move the notches from 16k and 32k to 64k and 128k. 

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