Datasheet

TMC429 DATASHEET (v. 1.07 / 2012-AUG-01) 37
Copyright © 2010-2012, TRINAMIC Motion Control GmbH & Co. KG
The bit continuous_update is also important for the automatic coil current scaling (see page 21). This
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Important Hint: The TMC429-I (SSOP16 package variant) hat only one left side reference switch
available when operating in step-direction mode.
REF_SW3_LEFT REF_SW2_LEFT REF_SW1_LEFT
SCK_S
SDO_S
SDI_S
nSCS_S
REF2 REF3
REF1
TEST GND
SDI_C
nSCS_C
SCK_C
SDO_C
CLK
V5V33
TMC428 / TMC429
+VCC+VCC+VCC
Figure 10-4: Reference switch configuration ‘left-side-only’ for mot1r=0 (and refmux=0)
SCK_S
SDO_S
SDI_S
nSCS_S
REF2 REF3
REF1
TEST GND
SDI_C
nSCS_C
SCK_C
SDO_C
CLK
V5V33
TMC428 / TMC429
+VCC
REF_SW1_RIGHT
+VCC
REF_SW2_LEFT REF_SW1_LEFT
+VCC
no reference switch for stepper motor 3
Figure 10-5: Reference switch configuration ‘two-one-null’ for mot1r=1 (and refmux=0)
SCK_S
SDO_S
SDI_S
nSCS_S
REF2R REF3
REF1R
TEST GNDCLK
V5V33
TMC429-LI
SCK_C
SDI_C
nSCS_C
SDOZ_C
nINT_SDO_C
REF1
REF3RREF2
SCK_S
SDO_S
SDI_S
nSCS_S
REF2R REF3
REF1R
TEST GNDCLK
V5V33
TMC429-PI24
SCK_C
SDI_C
nSCS_C
SDOZ_C
nINT_SDO_C
REF1
REF2
Figure 10-6: TMC429-LI has 3 right reference inputs / TMC429-PI24 has 2 right reference inputs