TMC457_1 TRINAMIC [TRINAMIC Motion Control GmbH & Co. KG.], TMC457_1 Datasheet - Page 13

• 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)
5.11 Sine Wave Look-up Table (SIN-LUT) Access and Parameterization
The TMC457 is equipped with an internal RAM (8192 addresses x 12 bit data) to hold a sine wave
look-up table for micro stepping. This look-up table has to be initialized first after power up of the
TMC457. Depending on the type of motor, a dedicated sine wave table has to be written into the
internal RAM of the TMC457. For both, 8192 values of 12 bit integer have to be calculated. The sine
LUT RAM is accesses via two register addresses, one for read and one for write.
Important Hint: When reading data from RAM, the read data are valid with the next read access. So,
the read data are pipelined with a delay of one SPI datagram.
5.11.1 Calculation of the Sine Wave Look-Up-Table to drive a Piezo Motor
5.11.2 Calculation of the Sine Wave Look-Up-Table to drive a Stepper Motor
With offset, to adjust current zero crossing, the formula becomes
The offset has a theoretical range of 0 to 4094. For a practical application, the offset will lie between 0
and 100. When using current scaling, the offset also becomes scaled down – this may be needed to be
taken into account!
Copyright © 2009 TRINAMIC Motion Control GmbH & Co. KG
y(x) = 4096 + 4095 * sin(2 * x/8192 – 2* /8) with x = 0, 1, 2, 3, …, 8189, 8190, 8191.
y(x) = abs( 4095 * sin(2 * x/8192) ) with x = 0, 1, 2, 3, …, 8189, 8190, 8191.
y(x) = offset + abs( (4095 - offset) * sin(2 * x/8192) ) with x = 0, 1, 2, 3, …, 8189, 8190, 8191.
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