LL6702 is a hybrid transformer for line applications. It is constructed using a C-core and meets requirements for high isolation between windings. The LL6702 has an extremely low leakage inductance and thus a flat frequency response curve. This makes it easy to design the balancing network for a good transhybrid loss in the entire frequency range. Two LL6702 transformers are required to build a complete hybrid.
Technical Specification:
Turns ratio: | 1.5, 1.5: 1+1 |
Dimensions: | 47(l) × 31(w) × 15(h) |
Spacing between pins: | 5.08mm (0.2") |
Spacing between rows of pins: | 30.48mm (1.2") |
Weight: | 70g |
Static resistance of primary (pins 1-4): | 50ohm |
Static resistance of balance (pins 2-5): | 45ohm |
Static resistance of each secondary (pins 6-7, 9-10): | 36ohm |
Max DC current: | 60mA |
Transhybrid loss (laboratory conditions): | 50dB, 10Hz-10kHz |
Isolation between windings: | 2kV/4kV |
Typical application: | Telephone hybrid using two LL6702 |
Balancing network ZB: | Select ZB for minimum crosstalk which occurs when ZB equals actual line impedance. In applications this is often accomplished with a combination of a potentiometer and a series of capacitors. |
Line termination: | If RI =RO, the termination impedance, ZT, as seen from the two-wire side is: |
| ZT (AC) =17ohm+RI +RD. Thus ZT is independent of ZB. |
| ZT (DC) =100ohm+RD. RD is an optional resistor used to reduce the line DC current. |