The MC100LVEL90 is a triple ECL to LVPECL translator. The device receives either -3.3 V or -5 V differential ECL signals, determined by the VEEsupply level, and translates them to +3.3 V differential LVPECL output signals.To accomplish the level translation, the LVEL90 requires three power rails. The VCCsupply should be connected to the positive supply, and the VEEpin should be connected to the negative power supply. The GND pins, as expected, are connected to the system ground plane. Both VEEand VCCshould be bypassed to ground via 0.015F capacitors.Under open input conditions, the Dbar input will be biased at VEE/2 and the D input will be pulled to VEE. This condition will force the Q output to a LOW, ensuring stability.The VBBpin, an internally generated voltage supply, is available to this device only. For single-ended input conditions, the unused differential input is connected to VBBas a switching reference voltage.BBmay also rebias AC coupled inputs. When used, decouple VBBand VCCvia a 0.01 5F capacitor and limit current sourcing or sinking to 0.5 mA. When not used, VBBshould be left open.