Circuit Project Description
The objective of the circuit is to build an electronic dice based on the functions of a 555 timer integrated circuit that operates in the astable mode.
Terminology LM555 – a highly stable device for generating accurate oscillation or time delays with additional terminals provided for resetting or triggering, used in linear ramp generator, pulse position and width modulation, time delay & pulse generation, sequential &precision timing, with features such as adjustable duty cycle, temperature stability, TTL compatible output, availability in 9-pin MSOP package, timing from microseconds, and operates in both astable & monostable modes4017 – a decade counter where the count advances as the clock input becomes high that may be combined with diodes for some functions such as flash sequencesBC550 – an NPN general purpose transistor with low current and low voltage used for low noise stages in audio frequency equipment Circuit Explanation
The 555 IC is a highly stable device for generating oscillation or accurate time delays used in pulse width/position modulation, sequential timing, time delay generation, linear ramp generator, precision timing, and pulse generation due to its features such as normally open and normally off output, temperature stability, output and supply TTL compatible, adjustable duty cycle, and operates in both astable and monostable mode.
The astable mode produces a continuous square wave or rectangular pulses as with an oscillator. In this circuit, the clock pulses are fed to the IC2 through the 10K Ohms resistor. A 10 stage counter is the main function of IC2 where the RESET at pin 15 is connected to the output 6 at pin 5 which gives a 6 stage counter where the output if from 0 to 5. Three pairs were formed from six of the LEDs which will require 4 different signals coming from the 4 transistors. The transistors are connected to the essential outputs of the IC2.
To prevent short circuits to occur between outputs, diodes are being used when a transistor is operated from more than one output. The INHIBIT at pin 13 of IC2 is connected to the positive emitter voltage through a 100K Ohms resistor which stops the counter from advancing. Pin 13 will only connect to 0 V line when the START button S1 is pressed since it is an open push switch. This will allow the counter to advance and will signify the throwing of the dice. The supply of the circuit may come from a 9 V battery source or from an external supply from 9 V to 12 V.
C2=10nF 100V MKT
D7…….13=Red Led 5mm
IC1=NE555 or LM555
S1=Normal Open Push switch
SL1=4pin connector 2.54mm step
BATT=9V battery or 12V ext.
The circuit for electronic dice can be seen mostly in role playing games and other types of board games. Some of the famous games include Monopoly, Snakes and the Ladder, Boggle, Dungeons and Dragons, Axis and Allies, and other games that will require random choices. The most acceptable advantage that the electronic circuit is to avoid the dice to be rolled off a table, which will eventually prevent cheating.