Project: bug-bot

Recently my daughter brought a journal from the local library. There was a bug bot my daughter said she wanted to make and it was dead simple. There was just one problem with that – I did not get how it could work at all – there was just a solar cell and the vibration motor just connected directly. The motor needs like constant 60mA of current, how is that possible that a tiny solar cell can provide that?

So I ordered cheap motors and cheap solar cells from a you-know-the-name website and guess what, it did not work.

two bots
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First order passive circuits (RC and LC)

First order networks are passive networks which includes a single element capable to store the energy (C or L). Let me try to derive the equations which will help us to understand the I/V characteristics with time.

RC and LC first order circuits
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Verilog-A: A PWM controller

Below is the procedure of a PWM veriloga controller created in Verilog-A language (behavioral description language)

So, I need a PWM controller which is basically the block the duty cycle of which will vary in dependence of the control pin voltage. The previous picture shows the output of the controller (red) with input applied control voltage (green). The frequency is constant.

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