Low Noise CW Filter, 9-pin DSUB

The LNF-320 is a common-mode filter designed to reduce noise on laser diodes driven by ILX Lightwave current sources using the standard 9-pin D-sub connector. The filter is designed to be used in series with the laser cable. A current source is a naturally high output impedance device, resulting in an increased susceptibility to noise pickup. The use of a filter will reduce the AC impedance and, therefore, reduce the radiated noise pickup at the output of the current source. This will not affect the DC performance of the current source. A common-mode structure is used to isolate the laser (load) ground from the current source ground. This will lessen noise induced by system ground loops.