Datasheet

TMC4361A Datasheet | Document Revision 1.22 • 2017-JAN-12
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© 2015 TRINAMIC Motion Control GmbH & Co. KG, Hamburg, Germany — Terms of delivery and rights
to technical change reserved. Download newest version at: www.trinamic.com .
Read entire documentation; especially the “Supplemental Directives” on page 224.
 MAIN MANUAL 
In order to set parameters and clipping values for PID regulation correctly, consider
the following details:
Large velocity variations are avoided by limiting v
PID
value with PID _ DV _ CLIP (register
0x5E). This clipping parameter limits both v
PID
and PID _ VEL .
The error sum PID _ ISUM (read out at 0x5B) is generated by the integral term.
PID _ ISUM is limited by setting PID _ I _ CLIP register 0x5D.
i The maximum value of PID _ I _ CLIP must meet the condition
PID_I_CLIP ≤ PID_DV_CLIP / PID_I .
i If the error sum PID_ISUM is not clipped, it is increased with each time step by
PID_I · PID_E . This continues as long as the motor does not follow.
Time scaling for deviation (with respect to error correction periods) is controlled by
PID_D_CLKDIV register.
i During error correction, fixed clock frequency f
PID_INTEGRAL
is valid:
f
PID_INTEGRAL
[Hz] = f
CLK
[Hz] / 128
The internal velocity VEL_ACT_PID alters actual ramp velocity VACTUAL . Two settings
are provided:
In case regulation_modus = b’11, VACTUAL is assigned as pulse generator base value
and VEL_ACT_PID is calculated by VEL_ACT_PID = VACTUAL + v
PID
.
In case regulation_modus = b’10, zero is assigned as pulse generator base value.
Now, VEL_ACT_PID = v
PID
is valid.
TMC4361A provides the programmable hysteresis PID_TOLERANCE for target position
stabilization; which avoids oscillations through error correction in case XACTUAL is
close to the real mechanical position.
The PID controller of TMC4361A is programmable up to approximate 100 kHz update
rate (at f
CLK
= 16 MHz). This high speed update rate qualifies PID regulation for motion
stabilization.
Now that PID control parameters and clipping values are configured, as explained
above, PID regulation can be enabled. Two options can be selected.
In order to enable PID control, do as follows:
Action:
OPTION 1: BASE PULSE GENERATOR VELOCITY = 0
 Set regulation_modus = b’10 ( ENC_IN_CONF register 0x07).
OPTION 2: BASE PULSE GENERATOR VELOCITY = VACTUAL
 Set regulation_modus = b’11 ( ENC_IN_CONF register 0x07).
Result:
PID regulation is enabled.
NOTE
 Detailed knowledge of a particular application (including dynamics of mechanics)
is necessary for PID controller parameterization.
PID Control
Parameters and
Clipping Values
PID_DV_CLIP
0x5E
PID_I_CLIP
0x5D (14:0)
PID_D_CLKDIV
0x5D (23:16)
VEL_ACT_PID
PID_TOLERANC
E 0x5F
Enabling PID
Regulation