I finished testing my high speed latest drives and should have a batch of prototype pcb's next week.
The New drives will run a full 300 Khz. The current Vipers can run about 150Khz max.
The New Viper 95 will also have a better voltage regulator. The current V95's would run hot if encoder draw was too high especiall at high voltages. Im now putting dual voltage regulators in the V95 so it has a separate regulator just for the encoder.
Manufacturer of CNC routers and Viper Servo Drives
www.LarkenCNC.com and www.Viperservo.com