Digital Electronics Board Game Counter Analog

Board Game Counter Demo - Analog 2 This presentation will Review the Board Game Counter block diagram. Review the circuit design of the analog section of the Board Game Counter. 2

Board Game Counter Block Diagram Analog Section Sequential Logic Section Combinational Logic Section The Analog Section produces a dampened square wave that “rolls” the count and slowly stops. On every pulse of the clock, the Sequential Logic Section increments a binary count from 1 to 6, then repeats. The Combinational Logic Section encodes the binary count into the die’s seven dots. CLOCK L1 L2 L3 L4 L5 L6 L7 ABCABC

Board Game Counter Block Diagram 4 Analog Section CLOCK Combinational Logic Section The Analog Section produces a dampened square wave that “rolls” the count and slowly stops. On every pulse of the clock, the Sequential Logic Section increments a binary count from 1 to 6, then repeats. The Combinational Logic Section encodes the binary count into the die’s seven dots. L1 L2 L3 L4 L5 L6 L7 Sequential Logic Section ABCABC

Analog Section 5 Schematic Diagram CLOCK

A Simplified Version 6 When the push button switch is pressed, the 100uf capacitor (C1) will quickly charge to 5 volts through the 1.2 k  resistor (R8). As long as the push button switch remains pressed, top end of the 10 k  resistor (R9) will be held at 5volts. This results in a simplified version that is equivalent to a standard 555 time oscillator. Actual VersionSimplified Version

Analysis of Simplified Version 7 Period: Frequency: RARA A RBRB C

Simulation of Simplified Version 8 V OUT VCVC

Simplified Version – Timing Analysis 9 Period: Frequency: V OUT VCVC

The Actual Version 10 When the push button switch is pressed and held, the actual analog section of the Board Game Counter performs like a standard 555 time oscillator. However, for the Board Game Counter to operate correctly, the oscillation must slow and eventually stop. This is where the 100uf capacitor (C1) and the 1.2 k  resistor (R8) play a role. Actual Version Simplified Version

Simulation of Actual Version 11 V OUT VCVC V Limit Push Button Pressed Push Button Released

Actual Version – Timing Analysis When the push button is pressed, the 555 Timer produces a  66 Hz square wave. Once the push button is released, the frequency gradually decreases (period increases). Eventually the oscillation will stop. 12 V OUT VCVC V Limit Push Button Pressed Push Button Released A C B

Timing Analysis at Time A 13 A Period: Frequency:

Timing Analysis at Time B 14 B Period: Frequency:

Timing Analysis at Time C 15 C Period: Frequency:

Board Game Counter – Analog 16 Sequential Logic Section Combinational Logic Section Analog Section Discussed in a future lesson