TMC457_1 TRINAMIC [TRINAMIC Motion Control GmbH & Co. KG.], TMC457_1 Datasheet - Page 9

• Manufacturer Part Number: TMC457_1
• Description: S-profile motion controller with PID feedback control and high resolution micro stepping sequencer for stepper motors and piezo motors
• Manufacturer: TRINAMIC [TRINAMIC Motion Control GmbH & Co. KG.]

TMC457 DATASHEET (V. 1.16 / 2009-Nov-25)
decimal mode, the lower 16 bit represent a number between 0 and 9999. This is especially important
for piezo motors (PiezoLEGS) because they do not have a fixed step length they achieve their very
high positioning precision in the range of nanometers via closed loop control together with a position
encoder. For stepper motors equipped with incremental encoders the fixed number representation
allows very comfortable parameterization. Additionally, gear can easily be taken into account.
The encoder counter named x_enc holds the current determined encoder position. Different modes
concerning handling of the signals A, B, and N take active low and active high signals of usual
incremental encoders into account. For details please refer to the register mapping section 6 Register
Mapping, page 14 ff.
The register enc_status holds the status concerning event of the ABN signals. The register enc_latch
stores the actual encoder position on an N signal event. The register x_latch stores the position while a
reference switch event occurs.
A register named enc_warn_dist (encoder warning distance) is used to generate an interrupt via the
TMC457 interrupt controller if the distance between encoder position and actual position is larger then
enc_warn_dist. The calculated error pid_e is available from the PID controller unit. Therefore, the PID
controller needs to be enabled.
5.2.1
Encoder example settings for motor parameters: 2048 µsteps, 200FS  409600 / U
Factor = FS*µS / EncPOS
Encoder example settings for a 200 fullstep motor with 2048 microsteps
200
360
500
1000
1024
3600
4000
4096
8192
16384
32768
5.3 Vector control
The vector control unit allows a load angle based motor control. This makes the motor behave like a
servo motor, i.e. it can be overloaded or stopped, and will later on catch up again, using the PID
regulator. Therefore, be careful to also activate the PID regulator!
Vector control is only possible using binary encoder resolutions, because no decimal setting is
available.
Copyright © 2009 TRINAMIC Motion Control GmbH & Co. KG
Encoder resolution
Setting the encoder to match the motor resolution:
2048
1137,7778
= 74565404,4444 / 2^16
= 11377777,7778 / 10000
819,2
= 53687091,2 / 2^16
= 8192000 / 10000
409,6
400
113,7778
102,4
100
50
25
12.5
required encoder factor
No exact match possible!
exact match with decimal setting
exact match with decimal setting
No exact match possible!
exact match with decimal setting
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