M401-01 – Frequency Generator and Meter, RS422

General Features

  • 2 explicit RS422 input units with 4 input channels 
  • One unit configurable to be either input or output with 3 input or output channels 
  • Input and output levels RS422 compliant 
  • Galvanic isolation of each unit against each other and against system supply 
  • Jitter (peak to peak): 10ns

Signal Input Features

  • The inputs of each unit can be configured as
    - Independent frequency meters 
    - Quadrature decoder with signal „A“, „B“ and „REF“ and an additional independent frequency meter (Unit 2 has no 4th input channel)
    - Binary inputs
  • 32bit signal edge counter 
  • Measuring principle: For each edge a time stamp is stored within a circular buffer 
  • Immediate detection of missing pulses and rapid slowing down of the frequency  
  • Quadrature decoding offers measuring of the following quantities 
  • Absolute angle
    - Referenced angle measuring with zero-point detection 
    - Simultaneous frequency & angle measurement

Signal Output Features

  • The output channels of unit 2 can be configured as
    - Independent frequency generators 
    - Quadrature encoder with signal „A“, „B“ and „REF“ 
    - Binary outputs
  • Continuous frequency range from 0 up to 25MHz. 
  • Accuracy and range of values meets 40bits 
  • 2 frequency update modes:
    - Immediate frequency change within the current period by integrating the angular velocity
    - New frequency values get active at the beginning of the next period
  • 3 pulse width modes:
    - Fixed high duration (independent from the period time) 
    - Fixed low duration (independent from the period time) 
    - Pulse width proportional to period time

Technical Data

Number of channels
  • 2 units with 4 input channels each 1 unit configurable as input or output with 3 channels
Input Channels 
Working voltage range
  • +/-0.2V <= Vdiff,in <= +/-5V RS422 compliant
Save voltage range
  • -20V .. 20V
Frequency range
  • 0 .. 2MHz
Sample rate
  • 100MHz
Circular buffer size
  • 512 x 32bit words for each channel
Input modes
  • Binary input mode (12 channels) 
  • Frequency meter mode (12 channels) 
  • Quadrature decoder mode (3 channels)
Output Channels 
Output voltage
  • +/-4V <= Udiff,Out <= +-5V
Output frequency range
  • 0 .. 25MHz
Frequency resolution
  • 10ns
Pulse width resolution
  • 10ns
Jitter (peak to peak)
  • 10ns
Output modes
  • Binary output mode (6 channels) 
  • Frequency generator mode (6 channels) 
  • Quadrature encoder mode (3 channels)
General Features 
Address space
  • A08 and A24
Available connectors
  • 25 Pin SubD connector, female

  • Measuring dynamic rotation speeds in dyno test systems 
  • Aquiring torque sensors outputs in dyno applications