[Dr_C2]

   

Chart showing the original fitted MOSFET part numbers for the following SSD decoders:

The left hand column is for the C8515 (revs F & G) and C7005.

The right hand column is for the C8515 rev H.

Clearly these MOSFETs can be used to replace failed MOSFETs and in doing so retain the OEM specification. All of these MOSFETs remain currently available.

The centre column provides an upgrade path for the C8515 (revs F & G) and C7005 which increases maximum motor current from 1.7Amps to 4.0Amps (at 25degC). If carrying out this upgrade the four rectifier diodes, also, should be upgraded as will be described in a separate post.

While not a current upgrade for the C8515 rev H, the same centre column also provides a useful repair route for the C8515 rev H. In this case the replacement MOSFETs add robustness against high voltage spikes thereby improving protection against electrostatic damage (ESD). This is achieved by integrating a pair of back-to-back Zeners.

So these are my suggestions as of 2024 for MOSFET repair and/or upgrade to SSD decoders.

If anyone wishes to try the centre column i.e. my suggestions (recommendations) - please let me know how you get on. 

c