Hammond 107L 10K CT to 3.2 Ohm Miniature Output Transformer

The 107L is a 107 Series miniature output transformer that steps a 10K ohm centre-tapped primary (pins 1-3) down to a 3.2 ohm secondary (pins 4-6). Its 55.3:1 turns ratio lets a high-impedance, low-current stage drive a small 3.2 ohm load directly from a PC board.

Power level is 150mw from 150 Hz. to 50 Khz., and the frequency range is 150 Hz. to 80 Khz. +/- 1.5db at +0, +10 and +20 dbm without D.C. saturation (response ±1.5db from 300Hz to 50KHz). Typical DCR is 650 ohms primary (370/280 ohms) and 0.36 ohms secondary, while the ordering table lists 780 and 0.65 ohms (+/- 20%). Primary inductance is 9.12 Hy and secondary 2.61 mH at 1.0 kHz, 1.0 V; impedance is 43.4 K ohms primary and 12.8 ohms secondary. Maximum D.C. unbalance is 1.5 mA and dielectric strength 100 Vrms.

Every 107 Series unit is epoxy potted in an attractive black molded case, and the rugged potting produces a completely sealed part that withstands severe environmental conditions. It will withstand soldering for 10 sec. at 260 degrees C, with a maximum ambient temperature of 85 degrees C; the casting epoxy has a workable range of -40°C to +105°C under a normal rate of change, not including thermal shock. With no centre tap on the 3.2 ohm secondary, pin 5 is omitted; the drawing notes the windings may be used either way round.

It mounts on a PC board with pin-type terminals of min. 0.187" length and is RoHS and REACH compliant, with a shipping weight of 0.02 lbs (0.01 kg).