User Manual

TMCM-102 Manual (V1.01 / 7 November 2007) 11

5.2.3 TMC428 Motion Controller

The TMC428 is a high-performance stepper motor control IC and can control up to three 2-phase-

stepper-motors (on this module, only one motor can be used). Motion parameters like speed or

acceleration are sent to the TMC428 via SPI by the microcontroller. Calculation of ramps and speed

profiles are done internally by hardware based on the target motion parameters.

5.2.4 TMC249 Motor Driver

The stepper motor driver used on the TMCM-102 module is the TMC249 chip. This driver is very

dependable, because it provides a variety of protection and diagnostic features, which even can be

read out by the user software. Its 16x up to 32x microstepping gives a quiet and precise motor

operation. A maximum coil current of 5.0A is supported by this driver IC together with the high

performance MOSFETs the module is equipped with.

5.3 Power Supply Requirements

The TMCM-102 is equipped with a switching voltage regulator that generates the 5V supply voltage for

the digital components of the module from the motor power supply. So only one supply voltage is

needed for the module. The power supply voltage can be 18..55V DC. Please note that there is no

protection against reverse polarity or too high voltage. The power supply typically should be within a

range of 24 to 48V to achieve highest motor performance. When using supply voltages near the

upper limit, a regulated power supply becomes a must. Please ensure, that enough power filtering

capacitors are provided in the system (2200µF or more recommended), in order to absorb mechanical

energy fed back by the motor in stalling conditions. In larger systems a zener diode circuitry might be

required, when motors are operated at high velocities.

The power supply should be designed in a way, that it supplies the nominal motor voltage at the

desired maximum motor power. In no case shall the supply value exceed the upper / lower voltage

limit. To ensure reliable operation of the unit, the power supply has to have a sufficient output

capacitor and the supply cables should have a low resistance, so that the chopper operation does not

lead to an increased power supply ripple directly at the unit. Power supply ripple due to the chopper

operation should be kept at a maximum of a few 100mV.

Therefore we recommend to

a) keep power supply cables as short as possible

b) use large diameter for power supply cables

c) if the distance to the power supply is large (i.e. more than 2-3m), use a robust 2200µF or

larger additional filtering capacitor located near to the motor driver unit.

5.4 Communication Interface

The TMCM-102 has a CAN and either RS422 or RS232 interface. RS422 and RS232 are ordering options.

Only one interface can be used at a time. All interfaces integrated on the module are ready-to-use, so

there are no external drivers or level shifters necessary. With an add on board the provided interfaces

are easier to access and additional serial interfaces like RS485 and USB are provided. Please check

[Standard add-on] manual for more information.