K8055 clamp and pwm

hi,

I have read many topics about clamps but i do not really understand how they work. does pwm stand for pulse width modulation? if it does, how come if i connect a small speaker to it no sound is created. also with the clamp. this is how ive connected it.

analog out (DAC1) into clamp
digital out 1 to LED to ground.

i raise my output voltage for DAC 1 to 3 volts and turn digital out 1 on. however the led does not light

The CLAMP is only to protect the output transistors when inductive load is connected to the digital outputs.
Both the digital outputs and PWM outputs are open collector outputs.
You have to connect the LED in series with a resistor (1k) between the digital output and external positive voltage source.
Connect the (-) of the external voltage source (e.g. a battery) to the GND of the card.

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