Circuit Microcontroller 68HC705
The microcontroller IC is a device that looks like a common IC. But inside it, the virtual a miniature computer. This device can be used instead of transistors and IC older those.
40 years ago Electronics fields used the transistors and ICs were equipment important the various circuit assemblie. but current dividend may become a memory. with the substitution of these microcontroller ICs.
Today, we can find microcontrollers have around us. They are used in appliances such as washing machines, microwave ovens, cell phones, printers, video recording, cameras, even in the car was also involved with the micro controller.
This ICs used is the number MC68HC705K1 manufactured by Motorola. Which it is ICs that cheaper, suitable for amateurs to experimentation and use study the performance of the micro-controller.
In the circuit as figure 1 has working as follows, inside IC1 will has The memory containing the program according to the needs of the user. For this training contains of the timer program there are two level are set 60 seconds and 90 seconds. Display a count down to 1 second.
List conponent
4.7K Resistors ¼ W 5%___________4 pcs.
100 ohm Resistors ¼ w 5%________1 pcs.
9.1K Resistors ¼ w 1%___________1 pcs.
27K Resistors ¼ w 1%____________1 pcs.
10 microfarad electrolytic capacitors__1 pcs.
0.1 microfarad ceramic capacitors____1 pcs.
100 picofarad ceramic capacitors
BC547_____45V 100mA NPN Transistor __1 pcs.
IC- LM2936__Ultra-Low Quiescent Current LDO Voltage Regulator
68HC705K1
MC14511___BCD–to–seven segment latch/decoder/driver IC
LED 7 Segment______________________2 pcs
Press Switch_________see text_________2 pcs.