TMC6200 DATASHEET (Rev. 1.01 / 2018-NOV-15)
11
Attention
In case VSA is supplied by a different voltage source, make sure that VSA does not drop out during
motor operation. The motor driver should be disabled in case VSA becomes switched off before VS.
Hard switching edges on VSA might result in bridge cross-conduction otherwise. It is safest to derive
VSA voltage from VS supply.
Attention
Make sure, that VCC_IO does not drop out during operation of the motor. Disable the drive when a
falling supply voltage is detected. It is safest to derive VCC_IO voltage from VS supply.
Hint
Production devices use VCC_IO undervoltage detection to disable the MOSFET drivers. This will avoid
motor overcurrent due to instable input levels during power-up / power-down for most cases.
However, it is best practice to disable the motor prior to switching off power supply, and to make
sure, that the motor power supply does come up without or not remain with missing VCC_IO supply.
Initial devices dated 1836 do not yet implement this VCC_IO controlled undervoltage reset of the
drivers.
3.2 External Gate Voltage Regulator
At high supply voltages like 48V, the internal gate voltage regulator and the internal 5V regulator
have considerable power dissipation, especially with high MOSFET gate charges or high chopper
frequency. A good thermal coupling of the heat slug to the system PCB GND plane is required to
dissipate heat. Still, the thermal thresholds will be lowered significantly by self-heating. To reduce
power dissipation, supply an external gate driver voltage to the TMC6200. Figure 3.2 shows the
required connection. The internal gate voltage regulator becomes disabled in this constellation. 12V
+/-1V is recommended for best results.
12V Gate Voltage
Supply
+VG
VSA
Gate Voltage
Regulator
12VOUT
100n
5VOUT
5V Regulator
2.2µ
Figure 3.2 External gate voltage supply
Hint
With MOSFETs above 50nC of total gate charge or chopper frequency >40kHz, it is recommended to
use a VSA supply not higher than 40V in order to keep reasonable power dissipation.
www.trinamic.com
TRINAMIC [ TRINAMIC MOTION CONTROL GMBH & CO. KG. ]
