Modulated Square Wave: Notes

2001 BMW 325Ci 2D Convertible, AutomaticSECTION Notes

A Modulated Square Wave is a series of High/Low signals repeated rapidly.

Like the switched signals (B+, B-) the square wave has only two voltage levels.

A high level and a low level.

Fig 1: Identifying Modulated Square Wave
G03389082Courtesy of BMW OF NORTH AMERICA, INC.

A modulated square wave has 3 characteristics that can be modified to vary the signal:

  • Frequency.
  • Pulse Width.
  • Duty Cycle.
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