Trinamic PD28-1-1021 User manual

MECHATRONIC DRIVE WITH STEPPER MOTOR PANdrive
TRINAMIC Motion Control GmbH & Co. KG
Hamburg, Germany
www.trinamic.com
Hardware Version V1.4
HARDWARE MANUAL
++PD28-1-1021
PD28-3-1021
+ +
UNIQUE FEATURES:
Stepper Motor NEMA11 / 28mm
0.06 - 0.12Nm
with Controller / Driver
up-to 0.7A RMS / 24V DC
sensOstep™Encoder
RS485 Interface

PD28-1-1021 / PD28-3-1021 V1.4 Hardware Manual (Rev. 1.03 / 2018-JAN-25)2
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Table of Contents
1Features........................................................................................................................................................................... 3
2Order Codes ................................................................................................................................................................... 5
3Mechanical and Electrical Interfacing..................................................................................................................... 6
3.1.1 Dimensions of PD28-1-1021 ....................................................................................................................... 6
3.1.2 Dimensions of PD28-3-1021 ....................................................................................................................... 7
3.2 Motor Characteristics .......................................................................................................................................... 8
3.3 Integrated sensOstep™ encoder .................................................................................................................... 9
3.4 Connectors........................................................................................................................................................... 10
3.4.1 Power, Communication and I/O Connector ........................................................................................ 11
3.4.2 Motor Connector.......................................................................................................................................... 17
4Motor driver current .................................................................................................................................................. 18
5Reset to Factory Defaults......................................................................................................................................... 21
6On-board LED............................................................................................................................................................... 21
7Operational Ratings ................................................................................................................................................... 22
8Torque Curves ............................................................................................................................................................. 24
9Functional description .............................................................................................................................................. 25
10 Life Support Policy..................................................................................................................................................... 26
11 Revision History.......................................................................................................................................................... 27
11.1 Document Revision........................................................................................................................................... 27
11.2 Hardware Revision ............................................................................................................................................ 27
12 References .................................................................................................................................................................... 28

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1Features
The PANdrive™ PD28-1-1021 and PD28-3-1021 are small and compact full mechatronic solutions including
NEMA11 / 28mm flange size stepper motors, the TMCM-1021 controller/ driver electronics and TRINAMIC
sensOstep™ encoder for step-loss detection. The two PANdrives include stepper motor with different
lengths and different holding torques (PD28-1-1021: 0.06Nm, PD28-3-1021: 0.12Nm) but, same electronics
and encoder setup. The PANdrives support both, stand-alone operation e.g. using the on-board I/Os
together with the build-in TMCL scripting feature and remote control operation using the RS485 2-wire
communication bus interface and even a mixture of both.
MAIN CHARACTERISTICS
Highlights
-Motion profile calculation in real-time
-On the fly alteration of motor parameters (e.g. position, velocity, acceleration)
-High performance microcontroller for overall system control and serial communication protocol
handling
-For position movement applications, where larger motors do not fit and higher torques are not
required
Bipolar stepper motor driver
-Up to 256 microsteps per full step
-High-efficient operation, low power dissipation
-Dynamic current control
-Integrated protection
-stallGuard2™feature for stall detection
-coolStep™feature for reduced power consumption and heat dissipation
Encoder
-sensOstep magnetic encoder (max. 1024 increments per rotation) e.g. for step-loss detection under all
operating conditions and positioning supervision
Interfaces
-Up to 4 multi-purpose inputs (2 shared with outputs)
-2 general purpose outputs
-RS485 2-wire communication interface
Software
-TMCL: standalone operation or remote controlled operation,
program memory (non volatile) for up to 876 TMCL commands, and
PC-based application development software TMCL-IDE available for free.
Electrical and mechanical data
-Supply voltage: +24V DC nominal (9… 28V DC)
-Motor current: up to 0.7A RMS (programmable)
-max. holding torque: 0.06Nm (PD28-1-1021) or 0.12Nm (PD28-3-1024)
Refer to separate TMCL Firmware Manual, too.

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TRINAMICS UNIQUE FEATURES –EASY TO USE WITH TMCL
stallGuard2™stallGuard2 is a high-precision sensorless load measurement using the back EMF on the
coils. It can be used for stall detection as well as other uses at loads below those which
stall the motor. The stallGuard2 measurement value changes linearly over a wide range of
load, velocity, and current settings. At maximum motor load, the value goes to zero or
near to zero. This is the most energy-efficient point of operation for the motor.
Load
[Nm]
stallGuard2
Initial stallGuard2
(SG) value: 100%
Max. load
stallGuard2 (SG) value: 0
Maximum load reached.
Motor close to stall.
Motor stalls
Figure 1.1 stallGuard2 load measurement SG as a function of load
coolStep™coolStep is a load-adaptive automatic current scaling based on the load measurement via
stallGuard2 adapting the required current to the load. Energy consumption can be reduced
by as much as 75%. coolStep allows substantial energy savings, especially for motors which
see varying loads or operate at a high duty cycle. Because a stepper motor application
needs to work with a torque reserve of 30% to 50%, even a constant-load application
allows significant energy savings because coolStep automatically enables torque reserve
when required. Reducing power consumption keeps the system cooler, increases motor
life, and allows reducing cost.
0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
0 50 100 150 200 250 300 350
Efficiency
Velocity [RPM]
Efficiency with coolStep
Efficiency with 50% torque reserve
Figure 1.2 Energy efficiency example with coolStep

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2Order Codes
The combination of motor and motor mounted controller/driver electronic is currently available with two
stepper motors (different length and holding torque).
The length of the PANdrives™ is specified without the length of the axis. For the overall length of the
product please add 21 mm (see detailed drawings in chapter 3).
Order code
Description
Size of unit [mm3]
PD28-1-1021-option
PANdrive with NEMA11 stepper motor, 0.06Nm max.
holding torque, TMCM-1021 electronics, 0.7A RMS, +24V,
RS485, sensOstep™ encoder
28 x 28 x 43 max.
PD28-3-1021-option
PANdrive with NEMA11 stepper motor, 0.12Nm max.
holding torque, TMCM-1021 electronics, 0.7A RMS, +24V,
RS485, sensOstep™ encoder
28 x 28 x 62 max.
Table 2.1 Order codes
The following options are currently available:
Firmware option
Description
Order code example:
-TMCL
Module pre-programmed with TMCL firmware
PD28-1-1021-TMCL
Table 2.2 PD28-1-1021 / PD28-3-1021 firmware options
A cable loom set is available for this module:
Order code
Description
TMCM-1021-CABLE
Cable loom for TMCM-1021
-1x cable loom for power, communication and I/O connector
(cable length approx. 200mm)
-1x cable loom for motor connector (cable length ca. 200mm)
Table 2.5 Cable loom order code

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3Mechanical and Electrical Interfacing
The PD28-1-1021 consists of the NEMA11 / 28mm flange size stepper motor QSH2818-32-07-006 with
controller / driver electronics TMCM-1021 mounted on its backside and integrated sensOstep™ encoder. The
PD28-3-1021 uses the longer QSH2818-51-07-012 NEMA11 / 28mm stepper motor together with the same
electronics and encoder.
Please see also stepper motor manuals and TMCM-1021 hardware and firmware manuals for more details.
Note:
In order to make proper use of the integrated sensOstep™encoder (the sensor IC is placed on the bottom
of the pcb) the TMCM-1021 electronics should not be removed/moved relative to the motor.
In case the integrated encoder feature is not used, the electronics may be moved or even removed from
the motor and placed somewhere else according to application requirements.
3.1.1 Dimensions of PD28-1-1021
The PD28-1-1021 consists of the stepper motor QSH2818-32-07-006, the TMCM-1021 controller / driver
electronics and integrated sensOstep™ encoder.
Figure 3.1 PD28-1-1021 dimensions (all dimensions in mm)

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3.1.2 Dimensions of PD28-3-1021
The PD28-3-1021 consists of the stepper motor QSH2818-51-07-012, the TMCM-1021 controller / driver
electronics and integrated sensOstep™ encoder.
Figure 3.2 PD28-3-1021 dimensions (all dimensions in mm)

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3.2 Motor Characteristics
Main characteristics of the two different motors available as part of the PD28-1-1021 (QSH2818-32-07-006)
and PD28-3-1021 (QSH2818-51-07-012):
Specification
Paramete
r
Units
QSH2818-32-07-006
QSH2818-51-07-012
Related PANdrive
PD28-1-1021
PD28-3-1021
Rated Voltage
VRATED
V
3.8
6.2
Rated Phase Current
IRMS_RATED
A
0.67
0.67
Phase Resistance at 20°C
RCOIL
Ω
5.6
9.2
Phase Inductance (typ.)
mH
3.4
7.2
Holding Torque (typ.)
Ncm
6
12
oz in
8.5
17.0
Detent Torque
Ncm
Rotor Inertia
g cm2
9
18
Weight (Mass)
Kg
0.11
0.2
Insulation Class
B
B
Insulation Resistance
Ω
100M
100M
Dialectic Strength (for one minute)
VAC
500
500
Connection Wires
N°
4
4
Step Angle
°
1.8
1.8
Step angle Accuracy (max.)
%
5
5
Flange Size (max.)
mm
28.0
28.0
Motor Length (max.)
LMAX
mm
32
51
Axis Diameter
mm
5.0
5.0
Axis Length (typ.)
mm
20.0
20.0
Shaft Radial Play (450g load)
mm
0.02
0.02
Shaft Axial Play (450g load)
mm
0.08
0.08
Maximum Radial Force
(20 mm from front flange)
N
28
28
Maximum Axial Force
N
10
10
Ambient Temperature
°C
-20…+50
-20…+50
Temp Rise (rated current, 2phase on)
°C
max. 80
max. 80
Table 3.1 NEMA 11 / 28mm technical motor data

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3.3 Integrated sensOstep™ encoder
The PD28-1-1021 and PD28-3-1021 PANdrive offer integrated sensOstep™ encoders based on hall sensor
technology. As the name “sensOstep™” already indicates intended use of this type of compact and highly
integrated encoder is step loss detection of motor movements. As soon as the motor has been moved to
a new location the position may be verified using this encoder feedback. In case the stepper motor has
lost one or multiple steps during movement e.g. due to overload / any obstacle encountered during
movement the motor axes will jump for at least one electrical period / 4 full steps. This can be detected
using the integrated encoder. In addition, step losses may be already detected during motor movements
using the “deviation” setting available as part of the TMCL firmware (see TMCM-1021 firmware manual for
more details).
While the encoder offers 10bit (1024 steps) resolution per motor revolution the absolute position
information is less accurate and depends on the displacement of the hall sensor based encoder IC relative
to the magnet and motor axis among other factors. Every PANdrive™ has been tested for maximum
deviation of +/- 5 encoder steps (static performance) relative to commanded microstep target position
during final tests after assembly at our factory. This will ensure more than adequate performance of the
integrated sensOstep™ encoder for step loss detection during motor movements.
Do not disassemble PANdrive™ when using integrated encoder
In order to make proper use of the integrated sensOstep™encoder (the sensor IC is placed
on the bottom center of the pcb) the TMCM-1021 electronics should not be removed/moved
relative to the motor! Otherwise encoder performance might suffer / not work.
Note: In case the integrated encoder feature is not used, the TMCM-1021 electronics may
be moved or even removed from the motor and placed somewhere else according to
application requirements.
Keep the electronics free of (metal) particles!
The integrated sensOstep™ encoder uses a magnet at the end of the motor axis in order
to monitor position of the motor axis. The magnet naturally attracts especially tiny metal
particles. These particles might be held on the top side of the PCB and even worse –start
moving in accordance with the rotating magnetic field as soon as the motor starts moving.
This might lead to shorts of electronic contacts / wires on the board and totally erratic
behavior of the module! Use compressed air for cleaning the module if necessary
(especially in prototype setups).
In order to prevent shorts and better protect the electronics the TMCM-1021 printed circuit
board is coated after assembly of components since hardware version V1.4.

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3.4 Connectors
The PD-1021 has two connectors, an 8-pin power and input/output connector and a 4-pin motor connector
(used to connect the attached motor).
Motor
Power / communication / I/Os
18
14
Figure 3.3 PD-1021 connectors
Overview of connector and mating connector types:
Label
Connector type
Mating connector types
Power,
communication
and I/O
CI0108P1VK0-LF
CVIlux CI01 series, 8pins, 2mm
pitch
Connector housing CVIlux: CI01085000-A
Contacts CVIlux: CI01T011PE0-A
or
Connector housing JST: PHR-8
Contacts JST: SPH-002T-P0.5S
Wire: 0.22mm2
Motor
CI0104P1VK0-LF
CVIlux CI01 series, 4 pins, 2mm
pitch
Connector housing CVIlux: CI01045000-A
Contacts CVIlux: CI01T011PE0-A
or
Connector housing JST: PHR-4
Contacts JST: SPH-002T-P0.5S
Wire: 0.22mm2
Table 3.2 Connectors and mating connectors, contacts and applicable wire

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3.4.1 Power, Communication and I/O Connector
An 8-pin, 2mm pitch single row connector is used for power supply, RS485 serial communication and
additional multi-purpose inputs and outputs.
Pin
Label
Direction
Description
1
GND
Power (GND)
GND
2
VDD
Power (Supply)
VDD, typ. +24V (+9V…+28V max.)
3
RS485+
Bidirectional
RS485 interface, diff. signal (non-inverting)
4
RS485-
Bidirectional
RS485 interface, diff. signal (inverting)
5
IN_0
Input
General purpose digital input,
+24V compatible, internal 20k pull-down resistor
Alternate function 1: Step input,
+24V compatible, internal 20k pull-down resistor.
Please note: the bandwidth of the low-pass (noise rejection) filter at
the input is 16kHz (-3dB) which will limit the upper step frequency
Alternate function 2: Left stop switch,
+24V compatible, internal 20k pull-down resistor
6
IN_1
Input
General purpose digital input,
+24V compatible, internal 20k pull-down resistor
Alternate function 1: Direction input,
+24V compatible, internal 20k pull-down resistor
Please note: the bandwidth of the low-pass (noise rejection) filter at
the input is 16kHz (-3dB)
Alternate function 2: Right stop switch,
+24V compatible, internal 20k pull-down resistor
7
OUT_0 / IN_2
Output / Input
Open drain output with freewheeling diode (max. 100mA)
Please note: there is a 20k pull-down resistor of the input connected
in parallel
Alternate function 1: general purpose digital input,
+24V compatible, internal 20k pull-down resistor
Alternate function 2:
home switch, +24V compatible, internal 20k pull-down resistor
8
OUT_1 / IN_3
Output / Input
Open drain output with freewheeling diode (max. 100mA)
Please note: there is a 20k pull-down resistor of the input connected
in parallel
Alternate function 1:
digital input, +24V compatible, internal 20k pull-down resistor
Alternate function 2:
analog input, 0..6.6V range, +24V survival, internal 20k pull-down
resistor
Table 3.2 8pin power, communication and I/O connector
3.4.1.1 Power supply
For proper operation care has to be taken with regard to power supply concept and design. Due to space
restrictions the PD28-1-1021 / PD28-3-1021 includes just about 20µF/35V (TMCM-1021 V1.2) resp. 30µF/35V
(TMCM-1021 V1.4) of supply filter capacitors. These are ceramic capacitors which have been selected for
high reliability and long life time. The module includes a 24V suppressor diode for over-voltage protection.
Please take the following measures into account in order to avoid serious damage of the device:
Add external power supply capacitors!
It is recommended to connect an electrolytic capacitor of significant size (e.g. 470µF/35V)
to the power supply lines next to the PD28-1-1021 / PD28-3-1021!
Rule of thumb for size of electrolytic capacitor: c = 1000 μF
A× ISUPPLY

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In addition to power stabilization (buffer) and filtering this added capacitor will also reduce
any voltage spikes which might otherwise occur from a combination of high inductance
power supply wires and the ceramic capacitors. In addition it will limit slew-rate of power
supply voltage at the module. The low ESR of ceramic-only filter capacitors may cause
stability problems with some switching power supplies.
Keep the power supply voltage below the upper limit of 28V!
Otherwise the driver electronics will seriously be damaged! Especially, when the selected
operating voltage is near the upper limit a regulated power supply is highly recommended.
Please see also chapter7, operating values.
There is no reverse polarity protection!
The module will short any reversed supply voltage due to internal diodes of the driver
transistors.
3.4.1.2 RS485
For remote control and communication with a host system the PD28-1-1021 / PD28-3-1021 provides a two
wire RS485 bus interface. For proper operation the following items should be taken into account when
setting up an RS485 network:
1. BUS STRUCTURE:
The network topology should follow a bus structure as closely as possible. That is, the connection
between each node and the bus itself should be as short as possible. Basically, it should be short
compared to the length of the bus.
c:> node
1
node
n- 1
node
n
Host Slave Slave Slave
RS485
termination
resistor
(120 Ohm)
termination
resistor
(120 Ohm)
}
keep distance as
short as possible
Figure 3.4: Bus structure
2. BUS TERMINATION:
Especially for longer busses and/or multiple nodes connected to the bus and/or high
communication speeds, the bus should be properly terminated at both ends. The PD28-1-1021 /
PD28-3-1021 does not integrate any termination resistor. Therefore, 120 Ohm termination resistors
at both ends of the bus have to be added externally.
3. NUMBER OF NODES:
The RS485 electrical interface standard (EIA-485) allows up to 32 nodes to be connected to a single
bus. The bus transceivers used on the PD28-1-1021 / PD28-3-1021 units (TMCM-1021 hardware V1.2:
SN65HVD3082ED, since hardware V1.4: SN65HVD1781D) have a significantly reduced bus load and
allow a maximum of 255 units to be connected to a single RS485 bus using TMCL firmware. Please
note: usually it cannot be expected to get reliable communication with the maximum number of
nodes connected to one bus and maximum supported communication speed at the same time.
Instead, a compromise has to be found between bus cable length, communication speed and
number of nodes.

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4. COMMUNICATION SPEED:
The maximum RS485 communication speed supported by the PD28-1-1021 / PD28-3-1021 is 115200
bit/s (FW version 1.29 with TMCM-1021 hardware version 1.2 and 1.4). Factory default is 9600 bit/s.
Please see separate TMCM-1021 TMCL firmware manual for information regarding other possible
communication speeds below 115200 bit/s.
5. NO FLOATING BUS LINES:
Avoid floating bus lines while neither the host/master nor one of the slaves along the bus line is
transmitting data (all bus nodes switched to receive mode). Floating bus lines may lead to
communication errors. In order to ensure valid signals on the bus it is recommended to use a
resistor network connecting both bus lines to well defined logic levels.
There are actually two options which can be recommended:
Add resistor (Bias) network on one side of the bus, only (120R termination resistor still at both
ends):
node
n- 1
node
n
Slave Slave
termination
resistor
(120R)
+5V
GND
pull-up (680R)
pull-down (680R)
RS485- / RS485B
termination
resistor
(220R)
RS485+ / RS485A
Figure 3.5: Bus lines with resistor (Bias) network on one side, only
Or add resistor (Bias) network at both ends of the bus (like Profibus™ termination):
node
n- 1
node
n
Slave Slave
termination
resistor
(220R)
+5V
GND
pull-up (390R)
pull-down (390R)
RS485- / RS485B
RS485+ / RS485A
termination
resistor
(220R)
+5V
GND
pull-up (390R)
pull-down (390R)
Figure 3.6: Bus lines with resistor (Bias) network at both ends
Certain RS485 interface converters available for PCs already include these additional resistors (e.g.
USB-2-485 with bias network at one end of the bus).
3.4.1.3 Digital Inputs IN_0 and IN_1
The eight pin connector of the PD28-1-1021 / PD28-3-1021 provides four general purpose inputs IN_0, IN_1,
IN_2 and IN_3. The first two inputs have dedicated connector pins while the other two share pins with
two general purpose outputs.

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All four inputs are protected using voltage resistor dividers together with limiting diodes against voltages
below 0V (GND) and above +3.3V DC. Input circuit of the first two inputs IN_0 and IN_1 is shown below:
+3.3V
IN_0,
IN_1
microcontroller
and stepper
motor driver
10k
10k
1nF
GND GND GND
Figure 3.7 General purpose inputs IN_0 and IN_1
The two inputs have alternate functions depending on configuration in software. The following functions
are available:
Label
(connector pin)
Default Function
Alternate function 1
Alternate function 2
IN_0 (5)
Digital input
+24V compatible,
internal 20k pull-
down resistor
Step signal input
(connected to stepper motor driver step
input)
+24V compatible, internal 20k pull-down
resistor.
Please note: the bandwidth of the low-pass
RC (10k / 1nF) filter at the input is 16kHz (-
3dB) which will limit the upper step
frequency
Left stop switch
+24V compatible,
internal 20k pull-
down resistor
IN_1 (6)
Digital input
+24V compatible,
internal 20k pull-
down resistor
Direction signal input
(connected to stepper motor driver
direction input)
+24V compatible, internal 20k pull-down
resistor.
Please note: the bandwidth of the low-pass
RC (10k / 1nF) filter at the input is 16kHz (-
3dB)
Right stop switch
+24V compatible,
internal 20k pull-
down resistor
Table 3.3 Multipurpose inputs / alternate functions
All four inputs are connected to the on-board processor and can be used as general purpose digital inputs.
Using the alternate function 1 of IN_0 and IN_1 it is possible to control the on-board stepper motor driver
with the help of an external stepper motor controller using step and direction signals (Please see separate
TMCL firmware manual / axis parameter 254 for more details how to enable this mode). For the step and
direction signals the signal levels are the same as for the general purpose digital inputs. Please note that
the low-pass filter (for noise rejection) at the inputs offers a bandwidth of 16kHz (-3dB).
IN_3 can be used as analog input, also. A 12bit analog to digital converter integrated in the microcontroller
will convert any analog input voltage between 0 and +6.6V to a digital value between 0 and 4095 then.
3.4.1.4 Inputs IN_2, IN_3, Digital Outputs OUT_0, OUT_1
The eight pin connector of the PD28-1-1021 / PD28-3-1021 provides two general purpose outputs. These
two outputs are open-drain outputs and can sink up to 100mA each. Both outputs OUT_0 and OUT_1 share
pins with two of the four inputs (IN_2 resp. IN_3).

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The inputs are protected using voltage resistor dividers together with limiting diodes against voltages
below 0V (GND) and above +3.3V DC. The circuit of the two outputs and the two inputs connected in
parallel to the inputs is shown below:
VDD
OUT_0 / IN_2
OUT_1 / IN_3
microcontroller
GND
+3.3V
microcontroller
10k
10k
1nF
GND GND GND
1k
GND
since V1.4
Figure 3.8 General purpose outputs OUT_0, OUT_1 and inputs IN_2, IN_3 connected in parallel
The outputs of the N-channel MOSFET transistors (Open-Drain) are connected to freewheeling diodes each
for protection against voltage spikes especially from inductive loads (relais etc.). Please take into account
the 20k (2x 10k in series) resistance to ground (transistor not active) of the input voltage divider (figure
4.8) when designing the external “load” circuit.
Since hardware version 1.4 the gate inputs of the MOSFETs are pulled-low during power-up and while the
processor might be still in reset / output pins not initialized. This way, the outputs will not briefly switch
on at power-up.
The two outputs OUT_0 / OUT_1 and inputs IN_2 / IN_3 have alternate functions depending on configuration
in software:
Label
(connector pin)
Default Function
Alternate function 1
Alternate function 2
OUT_0 / IN_2 (7)
Open drain output with
freewheeling diode (max.
100mA)
Please note: there is a 20k
pull-down resistor of the
input connected in parallel
Alternate function 1: general
purpose digital input,
+24V compatible, internal
20k pull-down resistor
Alternate function 2:
home switch, +24V
compatible, internal 20k
pull-down resistor
OUT_1 / IN_3 (8)
Open drain output with
freewheeling diode (max.
100mA)
Please note: there is a 20k
pull-down resistor of the
input connected in parallel
Alternate function 1:
digital input, +24V
compatible, internal 20k
pull-down resistor
Alternate function 2:
analog input, 0..6.6V range,
+24V survival, internal 20k
pull-down resistor
Table 3.4 Multipurpose outputs / inputs / alternate functions
Do not apply any voltage above supply voltage to inputs IN_2 and IN_3. Due to the
freewheeling diodes of the outputs connected in parallel they will be shorted to power supply
input voltage.

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For hardware version 1.2: Do not connect either IN_2 or IN_3 directly to a low resistance
supply voltage (e.g. directly to any power supply voltage). As the output transistors connected
in parallel might briefly switch-on during power-up they might be damaged / destroyed if the
current through the transistors to ground exceeds 100mA.

PD28-1-1021 / PD28-3-1021 V1.4 Hardware Manual (Rev. 1.03 / 2018-JAN-25)17
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3.4.2 Motor Connector
A 4-pin, 2mm pitch single row connector is used for connecting the four motor wires to the electronics.
Pin
Label
Direction
Description
1
OB2
Output
Pin 2 of motor coil B
2
OB1
Output
Pin 1 of motor coil B
3
OA2
Output
Pin 2 of motor coil A
4
OA1
Output
Pin 1 of motor coil A
Table 3.4 Motor connector
Do not connect or disconnect motor during operation!
Motor cable and motor inductivity might lead to voltage spikes when the motor is
disconnected / connected while energized. These voltage spikes might exceed voltage
limits of the driver MOSFETs and might permanently damage them. Therefore, always
disconnect power supply before connecting / disconnecting the motor.
For TMCM-1021 hardware version 1.4: please note the additional high current range
for motor currents up-to 1.4A RMS!
Setting motor current too high might lead to excessive power dissipation inside the motor,
overheating and even permanent damage of the motor. Therefore, make sure the motor
current is properly set. Also with hardware version 1.4 the low current range is set as
default. Do not use the high current range with the PD28-1-1021 and PD28-3-1021
PANdrives for prolonged time!
PD28-1-1021
PD28-3-1021
QSH2818-32-07-006
QSH2818-51-07-012
Motor connector pin
Cable colour
Coil
Description
1
Blue
B-
Motor coil B pin 2
2
Red
B
Motor coil B pin 1
3
Green
A-
Motor coil A pin 2
4
Black
A
Motor coil A pin 1
M
black
green
red
blue
A
B

PD28-1-1021 / PD28-3-1021 V1.4 Hardware Manual (Rev. 1.03 / 2018-JAN-25)18
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4Motor driver current
The on-board stepper motor driver operates current controlled. The driver current may be programmed in
software in two ranges (low current range up-to 0.7A RMS and high current range up-to 1.4A RMS) with 32
effective scaling steps in hardware for each range. Please note: the high current range is available with
TMCM-1021 hardware revision V1.4, only –not with hardware revision V1.2!
Be careful when setting motor current!
The stepper motors used for the PD28-1-1021 and PD28-3-1021 PANdrives have a rated
current of 0.67A RMS. Therefore, it is not recommended to use any current setting
significantly above the rated motor current –especially, not for prolonged amount of time.
Usually, it is not recommended to use the high current range settings with the PD28-1-
1021 and PD28-3-1021 PANdrives. Please carefully monitor motor temperature when
switching to high current settings.
Explanation of different columns in table below:
Motor current
setting in
software
(TMCL)
These are the values for TMCL axis parameter 6 (motor run current) and 7 (motor
standby current). They are used to set the run / standby current using the
following TMCL commands:
SAP 6, 0, <value> // set run current
SAP 7, 0, <value> // set standby current
(read-out value with GAP instead of SAP. Please see separate TMCM-1021 firmware
manual for further information)
Range setting
in software
(TMCL)
This is the value for TMCL axis parameter 179 (Vsense). This value defines the
current range. This value can be set using the following TMCL command:
SAP 179, 0, <value> // =0high current range
// = 1 low current range
For <value> either 0 (high current range) or 1 (low current range) is supported
(see table) since hardware revision V1.4. For earlier hardware revisions (incl. V1.2)
this parameter is set to the fixed value “1” (low current range).
(read-out value with GAP instead of SAP. Please see separate TMCM-1021 firmware
manual for further information)
Motor current
IRMS [A]
Resulting motor current based on range and motor current setting
Motor current
setting in
software (TMCL)
Range setting
in software
(TMCL)
Current
scaling step
(CS)
Motor
current
ICOIL_PEAK [A]
Motor
current
ICOIL_RMS [A]
0..7
1
0
0.034
0.024
8..15
1
1
0.069
0.049
16..23
1
2
0.103
0.073
24..31
1
3
0.138
0.097
32..39
1
4
0.172
0.122
40..47
1
5
0.206
0.146
48..55
1
6
0.241
0.170
56..63
1
7
0.275
0.194
64..71
1
8
0.309
0.219
72..79
1
9
0.344
0.243

PD28-1-1021 / PD28-3-1021 V1.4 Hardware Manual (Rev. 1.03 / 2018-JAN-25)19
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Motor current
setting in
software (TMCL)
Range setting
in software
(TMCL)
Current
scaling step
(CS)
Motor
current
ICOIL_PEAK [A]
Motor
current
ICOIL_RMS [A]
80..87
1
10
0.378
0.267
88..95
1
11
0.413
0.292
96..103
1
12
0.447
0.316
104..111
1
13
0.481
0.340
112..119
1
14
0.516
0.365
120..127
1
15
0.550
0.389
128..135
1
16
0.584
0.413
136..143
1
17
0.619
0.438
144..151
1
18
0.653
0.462
152..159
1
19
0.688
0.486
160..167
1
20
0.722
0.510
168..175
1
21
0.756
0.535
176..183
1
22
0.791
0.559
184..191
1
23
0.825
0.583
192..199
1
24
0.859
0.608
200..207
1
25
0.894
0.632
208..215
1
26
0.928
0.656
216..223
1
27
0.963
0.681
224..231
1
28
0.997
0.705
232..239
1
29
1.031
0.729
240..247
1
30
1.066
0.754
248..255
1
31
1.100
0.778
0..7
0
0
0.064
0.045
8..15
0
1
0.127
0,090
16..23
0
2
0.191
0.135
24..31
0
3
0.254
0.180
32..39
0
4
0.318
0.225
40..47
0
5
0.381
0.270
48..55
0
6
0.445
0.315
56..63
0
7
0.508
0.359
64..71
0
8
0.572
0.404
72..79
0
9
0.635
0.449
80..87
0
10
0.699
0.494
88..95
0
11
0.763
0.539
96..103
0
12
0.826
0.584
104..111
0
13
0.890
0.629
112..119
0
14
0.953
0.674
120..127
0
15
1.017
0.719
128..135
0
16
1.080
0.764
136..143
0
17
1.144
0.809
144..151
0
18
1.207
0.854
152..159
0
19
1.271
0.899
160..167
0
20
1.334
0.944
168..175
0
21
1.398
0.988
176..183
0
22
1.461
1.033
184..191
0
23
1.525
1.078
192..199
0
24
1.589
1.123
200..207
0
25
1.652
1.168
208..215
0
26
1.716
1.213
216..223
0
27
1.779
1.258
224..231
0
28
1.843
1.303
232..239
0
29
1.906
1.348
240..247
0
30
1.970
1.393

PD28-1-1021 / PD28-3-1021 V1.4 Hardware Manual (Rev. 1.03 / 2018-JAN-25)20
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Motor current
setting in
software (TMCL)
Range setting
in software
(TMCL)
Current
scaling step
(CS)
Motor
current
ICOIL_PEAK [A]
Motor
current
ICOIL_RMS [A]
248..255
0
31
2.033
1.438
Please note: these settings clearly exceed motor current rating for the PD28-1-1021 and PD28-3-1021
configurations!
In addition to the settings in the table the motor current may be switched off completely (free-wheeling)
using axis parameter 204 (see TMCM-1021 firmware manual).