ATOMI specifications

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Device variations[edit | edit source]

ATOMI is available in three different models. See also ATOMI device model comparison.

ATOMI DeepStep™
Basic model for stepper motor operation only
ATOMI Standard
Additional features and supported motor types
ATOMI Advanced
Most features

Main functionality[edit | edit source]

Function Description
Servo/stepping motor drive Closed loop control of various types of servo motors by sinusoidal field oriented control with dead-time distortion correction and high dynamic range torque control.
  • Synchronous AC & BLDC motors
    • Sinusoidal and trapezoidal commutated
    • SPM (Surface Permanent Magnet) and IPM (Internal Permanent Magnet) types
  • Brush DC motors
  • Linear motors
    • Iron core
    • Ironless (with external inductive filter)
  • Stepping motor, 2 phase (4,6 or 8 wires)
Control modes
  • Torque control
  • Velocity/speed control
  • Position control
Setpoint types

See setpoint signal / reference inputs list

Closed loop Cascaded control loops (PIV):
  • Torque / current control, update frequency 20.0 kHz
  • Velocity control, update frequency 2.5 kHz
  • Position control, update frequency 2.5 kHz
Feed-forwards Feed-forwards working in velocity & position control modes:
  • Acceleration (inertia canceling) feed-forward
  • Velocity (friction canceling) feed-forward
Homing Integrated homing function for position control mode:
  • Sensorless hard-stop homing
  • Home switch search
  • Index pulse search
  • Soft position limits (eliminate limit switches)
Feedback devices
  • Quadrature (incremental) encoders
  • Safe torque off with 3-way redundancy
  • Charge pump enable input
  • Stopping motor on errors
    • Tracking error (velocity & position)
    • Over speed error
    • Limit switch
  • DC motor runaway prevention on feedback loss
  • Communication error detection
  • Over current
  • Short circuit (phase-to-phase)
  • I2t motor thermal protection
  • Over & under voltage
  • Over temperature
Power supply
  • Externally supplied 12 – 49 VDC
  • Single power supply operation mode, no separate power supply needed for logic
Motor output current 1
  • AC/BLDC/Stepping/Linear motors (current specified as peak of sine):
    • 0 - 8 A
  • Brush DC motors:
    • 0 - 10 A
Compliance CE (LVD & EMC): EN 61800-5-1:2007, IEC 61000-6-1:2005 and IEC 61000-6-3:2006.


  • The device is Low Voltage Directive (LVD) compliant up to 42 VDC power supply, and above that level the supply voltage is considered hazardous, so external measures (such as or isolation or protective impedance) are necessary to prevent human contact to any circuit connected to the device.
  • In order to meet EMC standard requirements, a proper installation and wiring is necessary. Refer to user guide for proper installation.
  • MTBF: 660000 hours

1) Currents achievable continuously only with with sufficient coolant air flow. Without forced cooling, typically 30-45% of the maximum range can be driven continuously. Despite of this, maximum current is available for short periods of time even without cooling. Current is automatically throttled on temperature rise to protect the drive.

Motor output[edit | edit source]

Maximum output current throttling vs device temperature. Current is automatically reduced by device to protect from overheating.
Property Value Units Remarks
Supported motors Refer to ATOMI device model comparison page Permanent magnet motors only
Continuous output current 0-8 1 A (peak value of sine) User settable limit
Maximum effective motor phase output voltage
  • 3-phase AC motors: Vsupply*0.671 V RMS (phase-to-phase)
  • DC motors: Vsupply*0.95 VDC
  • I.e. at 48V supply, the maximum three-phase motor output voltage is 32.2 V RMS phase-to-phase
  • I.e. at 48V supply, the maximum DC motor output voltage is 45.6 V
Switching frequency 20.0 kHz
Maximum modulation depth 95  % Maximum effective output is 95% of HV DC bus voltage.
Torque control bandwidth (typ.) 1-3.3 kHz Motor coil dependent
Torque control cycle time 50.0 µs
Position & velocity control cycle time 400 µs
Power conversion efficiency 93-97  % Under typical conditions
Motor inductance range @ 48 VDC 0.2-25 mH
Motor inductance range @ 24 VDC 0.1-25 mH
Motor power range 0.01 - 0.5 kW
AC commutation frequency 0-400 Hz Not capped, may achieve up to 2 kHz

1) Maximum current is obtainable only for short periods without active air cooling. Drive automatically throttles current limit if drive temperature rises beyond 75 Celsius. Output current capacity reduces linearly between 75 and 90 degrees Celsius from the maximum to zero.

Regenerative resistor[edit | edit source]

ATOMI has an on-board 15 Ohm 11 Watt regenerative resistor.

Feedback devices[edit | edit source]

ATOMI supports quadradure (incremental) encoders with single-ended 3-5.5V (CMOS, TTL, open collector).

Quadrature encoder electrical properties[edit | edit source]

Property Value Units Remarks
Encoder count rate
  • ATOMI DeepStep™ and Standard: 0-4
  • ATOMI Advanced: 0-18
MHz After 4x decoding, digitally filtered
Supply voltage 4.8-5.2 V Supplied externally (can share same voltage with drive logic supply)
Encoder resolution
  • ATOMI DeepStep™ and Standard: 100-65535
  • ATOMI Advanced: 100-15000000
Pulses per revolution (P/R)

Setpoint signal / reference inputs[edit | edit source]

Setpoint signal type Status Electrical interface
Analog ATOMI Advanced only 0 - 3.3 V input signal. External circuitry needed for ±10 V operation.
Pulse and direction Standard feature

Maximum step rate

  • ATOMI DeepStep™ and Standard: 4 MHz
  • ATOMI Advanced: 8 MHz
PWM ATOMI Advanced only
  • 1 - 30 kHz PWM carrier frequency (fPWM), ~3 kHz for optimal operation.
  • Single signal (no polarity input), zero setpoint at 50% duty
  • PWM signal is sampled at 60MHz timer thus reading resolution is 60MHz/fPWM
  • PWM + Direction input mode
Serial communication Standard feature SimpleMotion V2 real-time serial bus with open source SDK. Connect through USB.
EtherCAT Planned Realized with add-on board

See also:

Mechanical[edit | edit source]

Dimension drawing
Property Value Units
Dimensions 160 × TBA (~17) × 91 (W×H×D) mm
Weight TBA kg

Note: all mounting holes are 3.2 mm diameter.

Electrical[edit | edit source]

Power supply[edit | edit source]

Input voltage Input current when idle Input current max
12 - 49 VDC Typically < 0.4 A Depends on total power output.

Note: ATOMI doesn't have an input diode for reverse input voltage protection (needed for some switching power supplies).

I/O[edit | edit source]

Please see ATOMI connectors and pinouts.

Environment[edit | edit source]

Property Value Units
Operating temperature 10 - 70 °C
Storage temperature -30 - 90 °C
Humidity 0 - 95 non-condensing  %

Warnings[edit | edit source]

In no event the Product Information or parts hereof shall be regarded as guarantee of conditions or characteristics. The Product Information or any part thereof may also not be regarded as a warranty of any kind. No liability of any kind shall be assumed by Author with respect to Product Information or any use made by you thereof, nor shall Author indemnify you against or be liable for any third party claims with respect to such information or any use thereof.

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