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Toroids: Powdered Iron

Use the table below to calculate inductance and number of turns per the following formulas.




Toroidal inductor equation formula
Where:
L = inductance in µH
AL = µ
H per 100 turns
N = number of full turns





AL Values
 Mix Type
Size2631512761012170
T-12n/a605048201817127.57.53.0
T-1614561554422n/a19138.08.03.0
T-201807655522724221610103.5
T-2523510085703429271912124.5
T-3032514093854337362516166.0
T-3727512090804032302515154.9
T-443601801601055246423318.518.56.5
T-503201751351004943403118186.4
T-684201951801155752473221217.5
T-804501801701155550453222228.5
T-9459024820016084n/a705832n/a10.6
T-106900450345325135133116n/an/an/a19
T-130785335025020011010396n/an/an/a15
T-157870420360320140n/a115n/an/an/an/a
T-1841640720n/a500240n/a195n/an/an/an/a
T-200895425n/a250120105100n/an/an/an/a


Iron Powder Magnetic Core Properties
MixColorMaterialμTemp
Stability
(ppm/°C)
f
(MHz)
Uses
26Yellow/WhiteHydrogen Reduced75825DC -1EMI filters, DC chokes
3GrayCarbonyl HP353700.05 - 0.50Exc. stability, good Q at low freq.
15Red/WhiteCarbonyl GS6251900.10 - 2Exc. stability, good Q
1BlueCarbonyl C202800.50 - 5Exc. stability, good Q at low freq.
2RedCarbonyl E10952 -30High Q
7WhiteCarbonyl TH9303 - 35Similar to mix 2 and mix 6, exc. temp stability
6YellowCarbonyl SF83510 -50Very good Q and temp. stability for 20-50 MHz
10BlackPowdered Iron W615030 - 100Good Q and stability for 40-100 MHz
12Green/WhiteSynthetic Oxide417050 - 200Good Q, moderate temp. stability
17Blue/YellowCarbonyl45040 - 180Similar to mix 12, better temp. stability, Q drops about 10% above 50 MHz, 20% above 100 MHz
0TanPhenolic10100 - 300L varies greatly with winding technique


Iron Powder Magnetic Core Dimensions
SizeColorDimensions (in)
O.D.I.D.Height
T-200-2Red2.001.250.55
T-94-2Red0.940.560.31
T-80-2Red0.800.500.25
T-68-2Red0.680.370.19
T-50-2Red0.500.300.19
T-37-2Red0.370.210.12
T-25-2Red0.250.120.09
T-12-2Red0.1250.060.05
T-50-10Black0.500.300.19
T-37-10Black0.370.210.12
T-25-10Black0.250.120.09
T-12-10Black0.1250.060.05
T-94-9Yellow0.940.560.31
T-80-6Yellow0.800.500.25
T-68-6Yellow0.680.370.19
T-50-6Yellow0.500.300.19
T-26-6Yellow0.250.120.09
T-12-6Yellow0.1250.060.05

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