I am working on testing out the AD5941 with a sweep from 1k to 100k. I am using the EVAL-AD5941ELCZ daughter board, and I am running the AD5940_BIA example code from Github to use the 4-wire method. In my test setup, I have a 10 ohm resistor as what I am trying to test. Thus, I would expect near zero for the phase measurement. In my results, I see what I would expect for a majority of the frequencies, but on a subset I see wild phase data. The magnitude seems within reason on those troublesome phase points. My customizations to the firmware example include:
- Adjusting RcalVal to 47.0 ohm to match the board
- Setting HstiaRtiaSel = HSTIARTIA_200 to match more closely to my 10 ohm resistor
Freq: 1000 RzMag: 13 RzPhase: 168.106
Freq: 2000 RzMag: 11 RzPhase: 146.309
Freq: 3000 RzMag: 11 RzPhase: 136.829
Freq: 4000 RzMag: 10 RzPhase: 128.206
Freq: 5000 RzMag: 9 RzPhase: 120.482
Freq: 6000 RzMag: 8 RzPhase: 113.617
Freq: 7000 RzMag: 7 RzPhase: 107.455
Freq: 8000 RzMag: 7 RzPhase: 0.454
Freq: 10000 RzMag: 7 RzPhase: 0.464
Freq: 11000 RzMag: 8 RzPhase: -107.4294966594
Freq: 12000 RzMag: 8 RzPhase: -113.4294966304
Freq: 13000 RzMag: 9 RzPhase: -120.4294966325
Freq: 14000 RzMag: 10 RzPhase: -128.4294966532
Freq: 15000 RzMag: 10 RzPhase: -137.4294966795
Freq: 16000 RzMag: 11 RzPhase: -147.4294967140
Freq: 17000 RzMag: 12 RzPhase: -157.4294966528
Freq: 19000 RzMag: 12 RzPhase: -169.4294967112
Freq: 20000 RzMag: 12 RzPhase: 167.619
Freq: 21000 RzMag: 11 RzPhase: 156.669
Freq: 22000 RzMag: 11 RzPhase: 146.581
Freq: 23000 RzMag: 10 RzPhase: 137.491
Freq: 24000 RzMag: 9 RzPhase: 129.223
Freq: 25000 RzMag: 8 RzPhase: 122.7
Freq: 26000 RzMag: 8 RzPhase: 115.445
Freq: 28000 RzMag: 7 RzPhase: 1.223
Freq: 29000 RzMag: 7 RzPhase: 1.267
Freq: 30000 RzMag: 7 RzPhase: 1.377
Freq: 31000 RzMag: 7 RzPhase: 1.398
Freq: 32000 RzMag: 8 RzPhase: -114.4294966411
Freq: 33000 RzMag: 8 RzPhase: -121.4294966474
Freq: 34000 RzMag: 9 RzPhase: -129.4294966815
Freq: 35000 RzMag: 9 RzPhase: -137.4294966362
Freq: 37000 RzMag: 10 RzPhase: -147.4294967047
Freq: 38000 RzMag: 11 RzPhase: -167.4294966517
Freq: 39000 RzMag: 11 RzPhase: -178.4294967180
Freq: 40000 RzMag: 10 RzPhase: -189.4294967010
Freq: 41000 RzMag: 10 RzPhase: -199.4294966734
Freq: 42000 RzMag: 9 RzPhase: -209.4294967129
Freq: 43000 RzMag: 9 RzPhase: -218.4294967291
Freq: 44000 RzMag: 8 RzPhase: -226.4294967244
Freq: 46000 RzMag: 8 RzPhase: -233.4294966885
Freq: 47000 RzMag: 7 RzPhase: 1.500
Freq: 48000 RzMag: 7 RzPhase: 1.596
Freq: 49000 RzMag: 7 RzPhase: 1.854
Freq: 50000 RzMag: 7 RzPhase: 1.580
Freq: 51000 RzMag: 7 RzPhase: 1.560
Freq: 52000 RzMag: 7 RzPhase: 1.579
Freq: 53000 RzMag: 7 RzPhase: 1.567
Freq: 55000 RzMag: 7 RzPhase: -130.4294966393
Freq: 56000 RzMag: 8 RzPhase: -147.4294966682
Freq: 57000 RzMag: 8 RzPhase: -156.4294966454
Freq: 58000 RzMag: 8 RzPhase: -166.4294966874
Freq: 59000 RzMag: 8 RzPhase: -176.4294967231
Freq: 60000 RzMag: 8 RzPhase: 174.112
Freq: 61000 RzMag: 8 RzPhase: 164.659
Freq: 62000 RzMag: 8 RzPhase: 155.662
Freq: 64000 RzMag: 7 RzPhase: 147.213
Freq: 65000 RzMag: 7 RzPhase: 1.390
Freq: 66000 RzMag: 7 RzPhase: 1.382
Freq: 67000 RzMag: 7 RzPhase: 1.341
Freq: 68000 RzMag: 7 RzPhase: 1.339
Freq: 69000 RzMag: 7 RzPhase: 1.389
Freq: 70000 RzMag: 7 RzPhase: 1.386
Freq: 71000 RzMag: 7 RzPhase: 1.292
Freq: 73000 RzMag: 7 RzPhase: 1.279
Freq: 74000 RzMag: 7 RzPhase: 1.252
Freq: 75000 RzMag: 7 RzPhase: 1.219
Freq: 76000 RzMag: 7 RzPhase: 1.232
Freq: 77000 RzMag: 7 RzPhase: 1.237
Freq: 78000 RzMag: 7 RzPhase: 1.234
Freq: 79000 RzMag: 7 RzPhase: 1.138
Freq: 80000 RzMag: 7 RzPhase: 1.270
Freq: 82000 RzMag: 7 RzPhase: 1.149
Freq: 83000 RzMag: 7 RzPhase: 1.224
Freq: 84000 RzMag: 7 RzPhase: 1.208
Freq: 85000 RzMag: 7 RzPhase: 1.144
Freq: 86000 RzMag: 7 RzPhase: 1.225
Freq: 87000 RzMag: 7 RzPhase: 1.209
Freq: 88000 RzMag: 7 RzPhase: 1.172
Freq: 89000 RzMag: 7 RzPhase: 1.92
Freq: 91000 RzMag: 7 RzPhase: 1.72
Freq: 92000 RzMag: 7 RzPhase: 1.93
Freq: 93000 RzMag: 7 RzPhase: 1.168
Freq: 94000 RzMag: 7 RzPhase: 1.156
Freq: 95000 RzMag: 7 RzPhase: 1.112
Freq: 96000 RzMag: 7 RzPhase: 1.162
Freq: 97000 RzMag: 6 RzPhase: 1.110
Freq: 98000 RzMag: 6 RzPhase: 1.112
Freq: 99000 RzMag: 6 RzPhase: 2.18
Freq: 1000 RzMag: 12 RzPhase: 156.780
Freq: 2000 RzMag: 11 RzPhase: 146.314
Freq: 3000 RzMag: 11 RzPhase: 136.833
Freq: 4000 RzMag: 10 RzPhase: 128.217
Freq: 5000 RzMag: 9 RzPhase: 120.487
Freq: 6000 RzMag: 8 RzPhase: 113.626
Freq: 7000 RzMag: 7 RzPhase: 107.460
Freq: 9000 RzMag: 7 RzPhase: 0.382
Freq: 10000 RzMag: 7 RzPhase: 0.482
Freq: 11000 RzMag: 8 RzPhase: -107.4294966611
Freq: 12000 RzMag: 8 RzPhase: -113.4294966315
Freq: 13000 RzMag: 9 RzPhase: -120.4294966340
Freq: 14000 RzMag: 10 RzPhase: -128.4294966544
Freq: 15000 RzMag: 10 RzPhase: -137.4294966804
Freq: 16000 RzMag: 11 RzPhase: -147.4294967154
Freq: 18000 RzMag: 12 RzPhase: -157.4294966455
Freq: 19000 RzMag: 12 RzPhase: 179.124
Freq: 20000 RzMag: 12 RzPhase: 167.636
Freq: 21000 RzMag: 11 RzPhase: 156.681
Freq: 22000 RzMag: 11 RzPhase: 146.593
Freq: 23000 RzMag: 10 RzPhase: 137.509
Freq: 24000 RzMag: 9 RzPhase: 129.232
Freq: 25000 RzMag: 8 RzPhase: 122.26
Freq: 27000 RzMag: 8 RzPhase: 115.384
Freq: 28000 RzMag: 7 RzPhase: 1.270
Freq: 29000 RzMag: 7 RzPhase: 1.266
Freq: 30000 RzMag: 7 RzPhase: 1.379
Freq: 31000 RzMag: 7 RzPhase: 1.405
Freq: 32000 RzMag: 8 RzPhase: -114.4294966434
Freq: 33000 RzMag: 8 RzPhase: -121.4294966499
Freq: 34000 RzMag: 9 RzPhase: -129.4294966827
Freq: 36000 RzMag: 9 RzPhase: -137.4294966330
Freq: 37000 RzMag: 10 RzPhase: -157.4294967100
Freq: 38000 RzMag: 11 RzPhase: -167.4294966547
Freq: 39000 RzMag: 11 RzPhase: -178.4294967213
Freq: 40000 RzMag: 10 RzPhase: -189.4294967066
Freq: 41000 RzMag: 10 RzPhase: -199.4294966795
Freq: 42000 RzMag: 9 RzPhase: -209.4294967193
Freq: 43000 RzMag: 9 RzPhase: -217.4294966358
Freq: 45000 RzMag: 8 RzPhase: -226.4294967220
Freq: 46000 RzMag: 7 RzPhase: 1.586
Freq: 47000 RzMag: 7 RzPhase: 1.538
Freq: 48000 RzMag: 7 RzPhase: 1.608
Freq: 49000 RzMag: 7 RzPhase: 1.858
Freq: 50000 RzMag: 7 RzPhase: 1.573
Freq: 51000 RzMag: 7 RzPhase: 1.587
Freq: 52000 RzMag: 7 RzPhase: 1.570
Freq: 54000 RzMag: 7 RzPhase: 1.497
Freq: 55000 RzMag: 8 RzPhase: -138.4294966358
Freq: 56000 RzMag: 8 RzPhase: -147.4294966683
Freq: 57000 RzMag: 8 RzPhase: -156.4294966506
Freq: 58000 RzMag: 8 RzPhase: -166.4294966928
Freq: 59000 RzMag: 8 RzPhase: -176.4294967251
Freq: 60000 RzMag: 8 RzPhase: 174.115
Freq: 61000 RzMag: 8 RzPhase: 164.684
Freq: 63000 RzMag: 8 RzPhase: 155.596
Freq: 64000 RzMag: 7 RzPhase: 1.407
Freq: 65000 RzMag: 7 RzPhase: 1.410
Freq: 66000 RzMag: 7 RzPhase: 1.385
Freq: 67000 RzMag: 7 RzPhase: 1.380
Freq: 68000 RzMag: 7 RzPhase: 1.377
Freq: 69000 RzMag: 7 RzPhase: 1.424
Freq: 70000 RzMag: 7 RzPhase: 1.329
Freq: 72000 RzMag: 7 RzPhase: 1.290
Freq: 73000 RzMag: 7 RzPhase: 1.238
Freq: 74000 RzMag: 7 RzPhase: 1.224
Freq: 75000 RzMag: 7 RzPhase: 1.243
Freq: 76000 RzMag: 7 RzPhase: 1.289
Freq: 77000 RzMag: 7 RzPhase: 1.308
Freq: 78000 RzMag: 7 RzPhase: 1.306
Freq: 79000 RzMag: 7 RzPhase: 1.218
Freq: 81000 RzMag: 7 RzPhase: 1.146
Freq: 82000 RzMag: 7 RzPhase: 1.141
Freq: 83000 RzMag: 7 RzPhase: 1.126
Freq: 84000 RzMag: 7 RzPhase: 1.152
Freq: 85000 RzMag: 7 RzPhase: 1.155
Freq: 86000 RzMag: 7 RzPhase: 1.128
Freq: 87000 RzMag: 7 RzPhase: 1.186
Freq: 88000 RzMag: 7 RzPhase: 1.123
Freq: 90000 RzMag: 7 RzPhase: 1.53
Freq: 91000 RzMag: 7 RzPhase: 1.104
Freq: 92000 RzMag: 7 RzPhase: 1.63
Freq: 93000 RzMag: 7 RzPhase: 1.126
Freq: 94000 RzMag: 7 RzPhase: 1.134
Freq: 95000 RzMag: 7 RzPhase: 1.87
Freq: 96000 RzMag: 7 RzPhase: 1.105
Freq: 97000 RzMag: 6 RzPhase: 1.133
What could I try adjusting to see better phase data? This seems quite repeatable which is why I posted to runs of the sweep.
Regards,
Gerry
