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Controller boards ET6, ET7, ET10 (breakout) have similar schematic design for outputs and binary outputs. It is standard open collector schematic. Darlington transistor array chip ULN2003 is used to drive outputs pins. According to ULN2003 datasheet transistors can drive up to 500mA current, however we recommend do not exceed 250mA.
Schematic is shown below -
There are 12 bit counter to program PWM outputs, PWM min value is “0”, PWM max value is “4095”.
To test output pins load resistor should be connected between output pin and +24V. Oscilloscope diagrams for PWM are shown below -
PWM=20 
PWM=500 mycnc-pwm-output-0500.bmp
PWM=2000 mycnc-pwm-output-1000.bmp
PWM=2000 mycnc-pwm-output-2000.bmp
PWM=3000 mycnc-pwm-output-3000.bmp
PWM=3980 mycnc-pwm-output-3980.bmp
