Tibeliusgatan 7 S-761 50 NORRTÄLJE SWEDEN Phone Fax International +46 - 176 13930 +46 - 176 13935 Domestic 0176-13930 0176-13935 Transformers for splitting LL1570 and LL1570XL The LL1570 is designed for splitting signals in application where large ground differences may appear, but is also very useful as a general purpose audio transformer. By careful design, the capacative coupling between the different part of the transformer is kept to a minimum. The three-section winding structure which is necessary for decoupling also results in a very high bandwidth. The transformer is built up from two coils, each with primary and secondary windings separated by electrostatic shields, and a high permeability mu-metal core. The two coil structure in combination with the mu-metal can results in high immunity to external magnetic fields. In the LL1570XL, the core is about 45% larger than in the LL1570, resulting in a larger level capability. Turns ratio: 1+1:1+1 Pin layout (viewed from component side) and winding schematics: 4 1 E2 5 7 2 6 6 4 8 3 7 8 E1 3 EP LL1570 (top view) 2 E2 1 5 E1 EP = Can and core Spacing between pins 5.08 mm (0.2") Spacing between rows of pins 27.94 mm (1.1") Offset of earth pin from adjacent row: 2.54 mm (0.1") Dimensions (Max. L x W x H above PCB(mm)) Weight: Static resistance of each primary: Static resistance of each secondary: Distortion (primary level, primaries connected in series, source impedance 800Ω ) Self resonance point : Optimum load for best square-wave response (secondaries. in series): Frequency response (source 600Ω, load as above, serial-serial connections): Isolation winding-winding / winding-shield / shield-shield + 4 E1 3 2 1 EP E2 8 LL1570 38 x 24 x 17 48 g 50 Ω 50 Ω 0.1% @ + 6 dBU, 50 Hz 1 % < @ +16 dBU, 50 Hz > 250 kHz 2.8 kΩ in series with 0.7 nF LL1570XL 38 x 24 x 20.5 65 g 62 Ω 62 Ω 0.1% @ + 9 dBU, 50 Hz 1 % < @ +19 dBU, 50 Hz > 250 kHz 2.8 kΩ in series with 0.7 nF 10 Hz -- 200 kHz +/- 0.5 dB 10 Hz -- 200 kHz +/- 0.5 dB 4 kV / 2 kV / 2 kV 4 kV / 2 kV / 2 kV Parallel-parallel connection (1 : 1) (e.g. mic input) Serial-serial connection (1 : 1) for line input or output + + 4 7 3 6 2 5 1 Recommended PCB hole diameter: 1.5 mm E1 EP + 8 Parallel-serial connection (1 : 2) (e.g. mic. input) + 4 7 3 6 2 5 1 E2 E1 8 + 7 EP E2 6 5 Parallel-split connection with separate grounds (1 : 1 + 1) 4 8 + E1 3 7 EP 2 + 1 6 E2 5 + R980616