The PLD-1315 and PLD-231X Series are designed to be backward compatible with industry standard sources and detectors used for single mode fiber applications. This form factor allows designers to offer single mode fiber performance in applications which currently use short wavelength (850 nm) devices in identical form factor packages . A link upgrade from multimode to single mode fiber can be done as easily as swapping out the optical components on the printed circuit board.
The PDL-1315M/TM is constructed using a 1300 nm Edge Emitting LED (ELED) . Such ELED’s efficiently couple their optical output into single mode optical fiber. Although a single mode emitter, driving the ELED can be done with the same circuitry used with multimode LED based components. Such circuitry is much simpler than that used with LASER based emitters given that no optical feedback is required with an ELED.
Two semiconductors make up the heart of the HFBR-231XM/TM receiver modules: a 75 um diameter InGaAs PIN photodiode and a silicon based trans-impedance amplifier (TIA). The PIN photodiode is optimized for high response in the 1300 nm wavelength region and has been teamed with a low noise TIA . The optical signals are detected by the PIN and converted to an analog voltage output with a very low input noise current contribution. The TIA is available with or without an Automatic Gain Control (AGC) circuit that decreases the light to voltage conversion factor when the average incident optical power is relatively high. There are three (3) versions of receivers available;
- PLD-2315M/TM: with AGC
- PLD-2316M/TM: no AGC and with same pin-out as the PLD-2315
- PLD-2317M/TM: no AGC and pin-out compatible with pcb’s designed for Agilent HFBR-2315 series
All of the receivers have differential output signals, but may also be operated in a single ended fashion by tying the negative output pin to ground.
The receiver offers a sensitivity better than –36 dBm at 100 MHz and with appropriate filtering a minimum overload value of 0 dBm. This large dynamic range make it ideal for both long and short range applications.