TMC428_06 Datasheet, PDF (5/58 Pages) List of Unclassifed Manufacturers – Intelligent Triple Stepper Motor Controller with Serial Peripheral Interfaces

TMC428 DATASHEET (v. 2.02 / April 26^th, 2006)
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the software point of view, the TMC428 provides a set of registers, accessed by a microcontroller (µC)
via a serial interface in an uniform way. Each datagram contains address bits, a read-write selection
bit, and data bits, to access the registers and the on-chip memory. Each time, the µC sends a
datagram to the TMC428, it simultaneously receives a datagram from the TMC428. This simplifies the
communication with the TMC428 and makes the programming easy. Most microcontrollers have an
SPI^TM hardware interface, which directly connects to the serial four wire microcontroller interface of the
TMC428. For microcontrollers without SPI^TM hardware, a software doing the serial communication is
completely sufficient and can easily be implemented.
2.3 Notation of Number Systems & Notation of Two to the Power of n
Decimal numbers are used as usual without additional identification. Binary numbers are identified by a
prefixed % character. Hexadecimal numbers are identified by a prefixed $ character. So, for example
the decimal number 42 in the decimal system is written as %101010 in the binary number system, and
it is written as $2A in the hexadecimal number system. With this, TMC428 datagrams are written as 32
bit numbers (e.g. $1234ABCD = %00010010001101001010101111001101). In addition to the basic
arithmetic operators (+, -, *, /) the operator two to the power of n is required at different sections of this
data sheet. For better readability instead of 2ⁿ the notation 2^n is used.
2.4 Signal Polarities
Per default, signals– external and internal –are high active, but the polarity of some signals is
programmable to be inverted. A pre-fixed lower case ‘n’ indicates low active signals (e.g. nSCS_C,
nSCS_S). For example the polarity of nSCS_S can be inverted by programming, but also the polarity of
datagram bits can be inverted by programming (see section 9, page 27).
2.5 Units of Motion Parameters
Motion parameters position, velocity, and acceleration are given as integer values within TMC428
specific units. Section 8.14 page 26 explains, how to calculate steps, steps per second, steps per
second square from given TMC428 integer values. With a given stepper motor resolution one can
calculate physical units for angle, angular velocity, angular acceleration.
2.6 Representation of Signed Values by Two’s Complement
Those motion parameters that have to cover negative and positive motion direction as well, are
processed as signed numbers represented by two’s complement as usual. Signed motion parameters
are x_target, x_actual, v_target, v_actual, a_actual. Limit motion parameters as v_min, v_max, a_max,
a_threshold, are represented as unsigned binary numbers.
2.7 Tables of Contents
A table of contents, a table of figures, and a table of tables are located at the end of the data sheet.
3 Package Variants
The TMC428 is available in three different package variants, qualified for the industrial temperature
range. An additional variant is available for the automotive temperature range. The package outlines
and dimensions are included within this data sheet (page 45-47.)
part number
TMC428-I
TMC428-A
TMC428-PI24
TMC428-DI20
Package
SSOP16 – 150 mils, 16 pins, plastic package, industrial (-40°C ... +85°C)
SSOP16 – 150 mils, 16 pins, plastic package, automotive (-40°C ... +125°C)
SOP24 – 300 mils, 24 pins, plastic package, industrial (-40°C ... +85°C)
DIL20 – 300 mils, 20 pins, plastic package, industrial (-40°C ... +85°C)
[This package variant is not recommended for new designs]
Table 3-1: TMC428 package variants
JEDEC Drawing
MO-137 (150 mils)
MO-137 (150 mils)
MS-013 (300 mils)
MS-001 (300 mils)
Copyright © 2004-2006, TRINAMIC Motion Control GmbH & Co. KG