Zeroplus Arduino starter kit with Logic Analyzer Manual page 87

REMARKS
1. PWM or pulse-width modulation is a type of digital signal used
for encoding a message into a pulsating signal that is mainly used
to allow the control of the voltage. Digital signals can only be
High or Low, but using a PWM, changing the proportion of time the
signal is High compared to when it is Low over a consistent time
interval, the output voltage can be set to an in-between state.
2. The transistor,
symmetrical. Pay attention to the pinout to avoid any damage.
as well as the temperature sensor, is non-
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