Hammond 1140-LU-CPC +18 dBu 80% Nickel PCB Line Output Transformer

The 1140-LU-CPC is a printed circuit mount line output transformer in the 1140-PC Series. It is a 600:600 impedance, 1:1 turns ratio transformer for designers who want a board-mounted, transformer-isolated line output with very low distortion.

Its drawing specifies bi-filar windings on an 80% nickel core, which gives very low distortion levels and good output levels. The 1140-LU-CPC can drive 600 Ω loads up to +18 dBu at 20 Hz. As with the other nickel-core parts, the drive signal should carry no DC component and the source impedance should be kept as low as possible.

Typical THD is 0.001% both at 1 kHz and at 20 Hz (4 dBu). The drawing gives frequency response of -0.05 dB at 20 Hz and +0.02 dB at 20 kHz, while the series ordering table lists -0.5 dB / +0.02 dB. Common mode rejection is 105 dB at 60 Hz and 85 dB at 3 kHz, and phase shift is 0.09° at 20 Hz and -0.75° at 20 kHz.

DC resistance is 40 Ω on each winding at 20°C. Primary input impedance is 680 Ω and secondary output impedance 80 Ω at 1 kHz. Capacitance is 20 nF primary to shield and case and 50 pF secondary to shield and case, with 250 Vrms dielectric strength. Pins: primary PIN 2–PIN 4, secondary PIN 11–PIN 8. Shipping weight is 0.2 lbs (0.09 kg); the part is RoHS and REACH compliant and marked Made in Canada.