Hi,
Is the LM628 suitable for motor control over a very wide speed range, i.e. >500,000:1?
Velocity control will be governed to a large extent by the resolution of the encoder attached, however, is it possible to explain how the LM628 behaves when the velocity required goes beyond that resolution at slow speeds? For example, with a 1000 line encoder the LM628 gives a positional resolution of 1/4000 rev. With a motor rated at 50 revs/sec max velocity that gives a speed range of 200,000:1 assuming one positional step per second. To achieve a target 500,000:1 will require interpolation over a longer time frame, is this feasible and if so what are the likely limits?
Many years ago I used a motion control interface, based on an LM628, with a linear power amplifier driving a DC servo motor and 1000line encoder. This configuration gave successful results however, the control interface is no longer available and it may be necessesary to replicate something similar for a new application. I will therefore be grateful of advice if this is still a viable solution.
Thanks in anticipation
Nigel
