LA 300 Series

ModelCurrentBus VoltagePower
4A Cont.
10A Peak
300W Cont.
600W Peak


Varedan LA 300 series are compact, high voltage, high current linear amplifiers designed to drive brushless and brush motors or voice coils. They are the perfect choice for systems requiring low radiated noise, zero distortion and extremely low drift from the drive electronics. With true class AB linear output stage (as opposed to PWM, pulse width modulation), the amplifiers are extremely quiet and provide very low distortion for smooth motor operation.

The design of these amplifiers includes an on- board highspeed DSP that monitors all key system functions in real time and provides protection for the outputs by limiting output power to a “Safe Operating Area”. An intelligent user interface allows setup and storage of all system parameters via the serial interface. Non-volatile memory provides storage of the parameters during power off conditions. A 7-segment LED display provides a visual indication of system status.

LA 310 provides 3 operation modes, T, S, D, selected via front edge DIP switch. In T mode, the amplifier is configured to drive one 3-phase brushless motor. In S mode, the amplifier is configured as a H-bridge to drive one single-phase motor or a voice coil. In D mode, the amplifier is configured as 3 independent half-bridges to drive up to 3 single phase motor or 3 voice coils.

LA 310 has 4 current loop gain settings, selectable via front edge DIP switch. Customer can utilize this feature to drive 4 different loads or drive one load with 4 different bandwidth settings.

Varedan offers 3 different packages, open-frame, DC stand alone and AC standalone. Open-frame module is an excellent selection for OEM applications. DC standalone module has a full covered enclosure with a cooling fan integrated. AC standalone integrates a 300W linear power supply and 2 cooling fans into the package. User can directly apply 110/240VAC power to the unit.


  • Linear output control for quiet motion control
  • Wide bus voltage +/-12 to +/-100 VDC
  • High output current +/-10A
  • 300 WATT continuous dissipation capability
  • Capability to drive up to 3 single phase motors and one 3-phase motor
  • 4 current loop gain settings
  • Up to 10KHz current loop bandwidth
  • Low current drift
  • Zero crossover distortion
  • Over current, voltage, temperature protection
  • Safety operation area protection
  • Non-volatile storage of all system parameters
  • 3 packages (Open-frame, DC standalone, AC standalone)
  • Smart fan control
  • Compact design to save panel space
  • 7-segment display shows status in real-time


Motor Phase A, B, C (T mode, 3-phase)
Motor Phase A, C (S mode, single phase H-bridge)
Motor Phase A, GND; B GND; C GND (D mode)
Current A, B, C (+/-5V, 2A/1V)
Fault (opto-isolated)
RS232 – Transmit


Current reference A, +/-10V, single-end or differential
Current reference B, +/-10V, single-end or differential
Current reference C, +/-10V, single-end or differential
Enable (opto-isolated)
RS232 – Receive


Operation Mode (T, S, D)
Motor Phase A and B bandwidth
Motor Phase C bandwidth
Current reference A and B transconductance ratio
Current reference C transconductance ratio


3-phase external 2-phase sinusoidal reference A and B


10KHz maximum


+/-100VDC maximum


7-segment LED for system status


Open-frame module
±DC motor bus supply
±15V bias supply (+15V@500mA, -15V@200mA)
DC standalone module
±DC motor bus supply
±15V bias supply (+15V@900mA, -15V@200mA)
AC standalone module
110VAC or 240VAC


I2T over current trip level and time
Absolute current trip level
Bus over voltage level
Input filter selection
Enable level
Enable source
Fan control mode


Safe operation area
Absolute over current
I2T over current
Bus over voltage
Bus under voltage
±15V under voltage
Internal logic voltage
Over temperature
DSP error
Non-volatile memory error


Open-frame module
Dimensions 7.15” x 3.45” x2.7”
Weight 2.0 lb
DC standalone module
Dimensions 10.17” x 3.82” x 3.67”
Weight 3.4 lb
AC standalone module
Dimensions 11.18” x 5.70” x 7.14”
Weight 15.0 lb


0 to 70 deg C ambient
-40 to 85 deg C storage
5% to 95% relative humidity. Non-condensing


Varedan Technologies warrants this product to be free of defects for a period of one year after the date of shipment and according to the Term and Conditions of Sale.