LL1581XL

      Tibeliusgatan 7 S-761 50 NORRTÄLJE SWEDEN Phone Fax International +46 - 176 13930 +46 - 176 13935 Domestic 0176-13930 0176-13935 LL1581XL Splitting Transformer In many splitting applications, the splitting transformer must have a high immunity to input common mode signals, to stray magnetic fields from e.g. power transformers and to large ground potential differences in receiving systems. The LL1581XL is developed to handle those types of problems. When designing the LL1581, we have used our well established two coil structure to create a transformer with a high degree of symmetry. The transformer is built up from two primary windings (which should be used in parallel) and two secondary windings. Each secondary winding is built up from two sections, one from each coil. Its own electrostatic shields surround each secondary section. The symmetric structure results in an internal cancellation of noise signals caused by external magnetic field. It also increase immunity to ground noise between secondary systems and reduces the effects of input common mode signals. The transformer is housed in a mu-metal can and is impregnated in solventless epoxy resin. Turns ratio: 1+1:1+1 Pin layout (viewed from component side) and simplified winding schematics: E 2 (+ core) 8 7 5 6 E 1 (+ can) 4 4 E2 3 2 1 LL1581 (top view) E1 5 7 6 8 3 1 2 Spacing between pins 5.08 mm (0.2") Spacing between rows of pins 27.94 mm (1.1") Offset of earth pins from adjacent row: 2.54 mm (0.1") Recommended PCB hole diameter: 1.5 mm 38 x 24 x 20.5 61 g 61 Ω 51 and 71 Ω > 200 kHz 0.1% @ +3 dBU, 50 Hz 1 % < @ +13 dBU, 50 Hz 10 Hz -- 100 kHz +/- 0.5 dB Frequency response (Ref : -6 dBu, 1kHz) Test arrangement: Parallel input - parallel output . Source 150Ω , load 10 kΩ > 60 dB CMRR at 20 kHz (Source 600 ohms, load 2 x 10k) > 40 dB CMRR at 20 kHz from sec. to sec. (Source 600 ohms, load 2 x 10k) Isolation test primary - secondary / secondary - secondary / E1 - E2 4 kV / 2 kV / 1 kV RMS Application example. Component side view. Dimensions (Max. L x W x H above PCB(mm)) Weight: Static resistance of each primary: Static resistance of each secondary (Pins 5 - 6 and pins 7 to 8): Self resonance point : Distortion Primary signal from microphone cable, with or without phantom power. Splitting 1: 1 + 1 4 E2 3 2 E1 7 6 5 8 + + 1 + Secondaries can be connected individually. (Function does not require that both secondaries are connected/used) R990105 LL1581XL Page 1 of 2       LL1581XL application example. 1 + 2 Out Splitting box On stage mic. 1 2 3 Front house desk. With phantom power supply Before connecting splitting box With splitting box On stage mic. 1 2 3 Front house desk. With phantom power supply Direct output 3 2 1 1 2 3 Splitting box 1 2 3 4 LL1581X 5 6 E1 E2 7 8 SW1 SW2 3 2 1 1 2 3 Monitor Desk 3 2 1 3 2 1 Recording Truck Ideally, SW1 and SW2 should be open. Close SW1 and / or SW2 when E1 and / or E2 do not receive ground reference from Monitor desk or from Recording truck respectively. LL1581XL Page 2 of 2 R990308