AFCM analog to Frequency Converter The AFCM configurable analog to frequency converter is used to convert analog standard signals to frequency signals or pulse width modulated (PWM) signals. The DIP switches are accessible on the side of the housing and allow the following parameters to be configured: - Input signal - Output values - Output type (frequency or PWM) - Filter type (for smoothing interferences on the input signal) - Input over/under range fault detection