CHAPTER 27 ■ ENCORE
- 1 pF to 1 mF: used in moderately accurate timing circuits.
- 1 pF to 40 pF: vital for high-accuracy crystal-based oscillator circuits, especially those
for microcontrollers and microprocessors.
As would be expected, the greater the maximum voltage and the greater the capacity, the larger the
physical size of the capacitor. In Figure 27-4, the second and third capacitors are the same physical size.
The one on the left has a smaller maximum voltage but greater capacity; the one of the right has a larger
maximum voltage but smaller capacity.
Figure 27-4. Various capacitors: (left to right) 2.5 V 1 F electrolytic, 6.3 V 4700 mF electrolytic, 16 V 2200 mF
electrolytic, 10 mF tantalum, 0.1 mF monolithic ceramic, 24 pF ceramic disc
Figure 27-5. Various solar panels
Solar Power
A robot that continues to operate autonomously without regular human intervention seems more alive than
a robot that dies when its battery runs down. The ability to independently recharge, either by returning to a
power station or via solar panels, is a real milestone in robot design.
A big problem with small solar panels (see Figure 27-5) is that they don’t provide nearly enough
continuous power for a motorized robot. You can overcome this byhaving the solar panels recharge a battery
or capacitor, and also by limiting motor activity to short, daylight trips.