robismyname
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I measured "Z" of a 1pF capacaitor: passive plus,inc. (0402N1R0BW500) over a frequency range of 2390MHz - 2500MHz
The "Real" part of Z is different by about 10 ohms across the two test parts. Two seperate parts were used from the same reel
Can someone offer a logical explanation to how or why this exist? Perhaps it due to temperature? Perhaps I added more solder on the test fixture to mount the cap than I did in the previous test? Is this a big deal?
W=ohms
Test set 1
Freq
(MHz) Real Imaginary capacitance
2390 20.4 W - 38.4 j 1.7 pF
2395 20.2 W - 37.3 j 1.8 pF
2400 19.8 W - 36.6 j 1.8 pF
2405 18.9 W - 35.6 j 1.9 pF
2410 18.7 W - 34.4 j 1.9 pF
2415 18.6 W - 33.5 j 2 pF
2420 18.4 W - 32.3 j 2 pF
2425 18.2 W - 31.2 j 2.1 pF
2430 17.9 W - 30.2 j 2.2 pF
2435 17.8 W - 29.2 j 2.2 pF
2440 17.7 W - 28.1 j 2.3 pF
2445 17.6 W - 26.9 j 2.4 pF
2450 17.6 W - 26 j 2.5 pF
2455 17.7 W - 25 j 2.6 pF
2460 17.7 W - 24.3 j 2.7 pF
2465 17.8 W - 23.4 j 2.8 pF
2470 17.8 W - 23 j 2.8 pF
2475 17.5 W - 21.9 j 2.9 pF
2480 17.7 W - 21.1 j 3 pF
2485 17.9 W - 21.2 j 3.2 pF
2490 17.9 W - 19.3 j 3.3 pF
2495 18 W - 18.8 j 3.4 pF
2500 18.1 W - 18.1 j 3.5 pF
Test Set 2
W = ohms
Freq
(MHz) Real Imaginary capacitance
2390 30.2 W - 37.4 j 1.7 pF
2395 29.9 W - 36.5 j 1.8 pF
2400 29.5 W - 35.4 j 1.87 pF
2405 29.1 W - 34.5 j 1.92 pF
2410 28.7 W - 33.5 j 1.98 pF
2415 28.2 W - 32.51 j 2.02 pF
2420 27.9 W - 31.5 j 2.09 pF
2425 28 W - 30.57 j 2.15 pF
2430 27.6 W - 29.5 j 2.2 pF
2435 27.7 W - 28.4 j 2.3 pF
2440 27.6 W - 27.4 j 2.3 pF
2445 27.51 W - 26.4 j 2.45 pF
2450 27.5 W - 25.7 j 2.51 pF
2455 27.3 W - 24.9 j 2.6 pF
2460 27 W - 24.15 j 2.6 pF
2465 27.1 W - 23.4 j 2.8 pF
2470 27 W - 22.7 j 2.8 pF
2475 27.1 W - 22.2 j 2.89 pF
2480 26.8 W - 21.9 j 2.9 pF
2485 26.9 W - 20.9 j 3.04 pF
2490 26.7 W - 20.3 j 3.14 pF
2495 26.8 W - 19.64 j 3.24 pF
2500 27.2 W - 19.1 j 3.3 pF
The "Real" part of Z is different by about 10 ohms across the two test parts. Two seperate parts were used from the same reel
Can someone offer a logical explanation to how or why this exist? Perhaps it due to temperature? Perhaps I added more solder on the test fixture to mount the cap than I did in the previous test? Is this a big deal?
W=ohms
Test set 1
Freq
(MHz) Real Imaginary capacitance
2390 20.4 W - 38.4 j 1.7 pF
2395 20.2 W - 37.3 j 1.8 pF
2400 19.8 W - 36.6 j 1.8 pF
2405 18.9 W - 35.6 j 1.9 pF
2410 18.7 W - 34.4 j 1.9 pF
2415 18.6 W - 33.5 j 2 pF
2420 18.4 W - 32.3 j 2 pF
2425 18.2 W - 31.2 j 2.1 pF
2430 17.9 W - 30.2 j 2.2 pF
2435 17.8 W - 29.2 j 2.2 pF
2440 17.7 W - 28.1 j 2.3 pF
2445 17.6 W - 26.9 j 2.4 pF
2450 17.6 W - 26 j 2.5 pF
2455 17.7 W - 25 j 2.6 pF
2460 17.7 W - 24.3 j 2.7 pF
2465 17.8 W - 23.4 j 2.8 pF
2470 17.8 W - 23 j 2.8 pF
2475 17.5 W - 21.9 j 2.9 pF
2480 17.7 W - 21.1 j 3 pF
2485 17.9 W - 21.2 j 3.2 pF
2490 17.9 W - 19.3 j 3.3 pF
2495 18 W - 18.8 j 3.4 pF
2500 18.1 W - 18.1 j 3.5 pF
Test Set 2
W = ohms
Freq
(MHz) Real Imaginary capacitance
2390 30.2 W - 37.4 j 1.7 pF
2395 29.9 W - 36.5 j 1.8 pF
2400 29.5 W - 35.4 j 1.87 pF
2405 29.1 W - 34.5 j 1.92 pF
2410 28.7 W - 33.5 j 1.98 pF
2415 28.2 W - 32.51 j 2.02 pF
2420 27.9 W - 31.5 j 2.09 pF
2425 28 W - 30.57 j 2.15 pF
2430 27.6 W - 29.5 j 2.2 pF
2435 27.7 W - 28.4 j 2.3 pF
2440 27.6 W - 27.4 j 2.3 pF
2445 27.51 W - 26.4 j 2.45 pF
2450 27.5 W - 25.7 j 2.51 pF
2455 27.3 W - 24.9 j 2.6 pF
2460 27 W - 24.15 j 2.6 pF
2465 27.1 W - 23.4 j 2.8 pF
2470 27 W - 22.7 j 2.8 pF
2475 27.1 W - 22.2 j 2.89 pF
2480 26.8 W - 21.9 j 2.9 pF
2485 26.9 W - 20.9 j 3.04 pF
2490 26.7 W - 20.3 j 3.14 pF
2495 26.8 W - 19.64 j 3.24 pF
2500 27.2 W - 19.1 j 3.3 pF