User Manual

TMCM-343 Hardware Manual (V1.07 / 2011-JUN-08) 9

5.3 Power supply requirements

Two different power supplies have to be provided for the TMCM-343: +5VDC for the controller part and

+7… 34VDC for the motor supply. Please connect all listed pins for the power supply inputs and

ground in parallel. It is recommended to use capacitors of some 1000µF and a choke close to the

module for the motor supply. This ensures a stable power supply and minimizes noise injected into

the power supply cables. The choke especially becomes necessary in larger distributed systems using

a common power supply.

TMCM-343

V_ Motor

(7... 34V)

GND

C (> 1000µF)

Power Supply

keep distance short

Local +5V

regulator

supply for further modules on

same base board

Figure 5.4: Power supply requirements for TMCM-343

Especially in bus controlled systems (e.g. CAN or RS485) it is important to ensure a stable ground

potential of all modules. The stepper driver modules draw peak currents of some ampere from the

power supply. It has to be made sure, that this current does not cause a substantial voltage

difference on the interface lines between the module and the master, as disturbed transmissions

could result.

The following hints help avoiding transmission problems in larger systems:

 Use power supply filter capacitors of some 1000µF on the base board for each module in order to

take over current spikes. A choke in the positive power supply line will prevent current spikes

from changing the GND potential of the base board, especially when a central power supply is

used.

 Optionally use an isolated power supply for the TMCM-Modules (no earth connection on the

power supply, in case the CAN master is not optically decoupled)

 Do not supply modules which are mounted in a distance of more than a few meters with the

same power supply.

 For modules working on the same power supply (especially the same power supply as the

master) use a straight and thick, low-resistive GND connection.

 Use a local +5V regulator on each baseboard.