I need an small isolation transformer for 0-6V 400Hz AC (this is my external signal, amplitude is the value):
I should get <10mA load from the primary signal source, and in the same time I need minimal size of the transformer. For <10mA at 6V 400 Hz the primary inductance should be >238 mH (coil impedance is \$2\pi f L\$).
Typical transformers that I found with such an inductance is pretty big, but I found also Bourns LM-LP-1001L that have very confusing values in datasheet. Help me please understand it.
The datasheet says that DC resistance of primary coil is 90Ω, and impedance at 1kHz is 600Ω, so I calculated the coil's inductance 81 mH. But datasheet says inductance is 2.8H! What is wrong here? And if 2.8H is the correct value, how do so small transformer can have so big inductance?