Hello,
can I get application notes about right EA Bias configuration?
It's not fully clearly what frequency range applied into this point of scheme (input of TOSA). We don't sure it should be 9-11 GHz or 4-6 Ghz. As result we can't calculate filter correctly.
We need some recommendations about filter implementation for this device.
Best regards
Hi Vladimir,
The EA Bias is the voltage bias that is required to drive the EML-modulator inside the TOSA. It is typically around -0.7V, but can be anywhere between -0.3V to -1.1V or even lower, depending on the Voltage-Power response characteristics of the modulator inside the TOSA being used.
A bias-T from VCC to the TXOUT+ pin is required to supply sufficient headroom voltage for the output driver transistors. It is recommended that the inductance in the bias-T have low DC resistance to limit the DC voltage drop and maximize the voltage supplied to the TXOUT+ pin. If the voltage on this pins drops below approximately 2.1V then the output rise and fall times can be adversely affected.
The complete schematics of the design around this bias-T and the other pins is given along with the corresponding passive component recommendations (in BOM) in the EVM User guide that can be found online at:
Thanks,
Sri
