TMC389 Datasheet, PDF (46/48 Pages) TRINAMIC Motion Control GmbH & Co. KG. – three phase stepper motor driver

TMC389 DATASHEET (V. 1.15 / 2015-OCT-27)
46
18 Using an external power stage for higher voltage or current
The TMC389 uses a completely complementary driving scheme for power transistors. This allows
attaching an external gate driver, using the low side driver output information, only. Therefore, the
external gate driver needs to bring brake-before make capability. You can directly attach gate driver
ICs like TMC603 as gate drivers for high current NMOS transistor bridges. The TMC603 also supplies
a gate drive voltage regulator and allows 100% duty cycle. Please refer TMC603 datasheet. The
example shows the TMC603 driver boosting TMC389. The higher gate driving capability allows
addressing designs for more than 20A. Different gate driver ICs are available on the market which also
allow for higher voltages.
+V12
12V gate
supply
100n
16V
VHS
+VCC
TMC389
3.3V or 5V
VCC_IO
D
100n
8-20MHz
CLK
D
step & dir
(optional)
STEP
D
DIR
D
100n
VM
5VOUT
+VCC
BBM_EN
470nF
HW
HU
HV
BMW
BMU
BMV
+V12
BH1
BL1
TEST_SE
D
ENABLE
D
CSN
D
SCK
D
SPI
SDI
D
SDO
D
LW
BH2
LV
LU
BL2
stallGuard
output
SG_TST
D
BH3
SR
DIE PAD
GND TEST_ANA
BL3
INV_BL
+V12
VLS VCP VM
+VM _12-48V
supply
TMC603
HS-DRV
LS-DRV
HS1
Z 12V
BM1
220R
LS1
HS-DRV
LS-DRV
+VM
HS2
Z 12V
BM2
220R
LS2
HS-DRV
LS-DRV
+VM
HS3
Z 12V
BM3
220R
LS3
RNAME
3 phase
stepper
motor
figure 19: High current high voltage power stage using additional gate drivers (example)
Please be aware, that the short to GND protection of the TMC389 cannot be used in this scheme: The
driver cannot be fully disabled, because the external gate driver just switches on either high side
MOSFET or low side MOSFET. An external short to GND protection could use a series resistor to
measure power bridge current and to disable the high side MOSFETs by using the TMC389 enable
input ENN. Use a gate driver like TMC603 to provide additional short to GND protection without the
need for a high side shunt.
Copyright © 2010 TRINAMIC Motion Control GmbH & Co. KG