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SE-3910 Real-time Systems. Week 2, Class 2 Return stuff, New HW Assignment! Quiz! (Possibly with review) Ohm’s Law Kirkhoff’s Current Law Switches Using/reading an oscilloscope Frequency / Period Signals Square, Sine, Saw-tooth, Random Pulse Width Modulation (PWM). Waveform Terminology.
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SE-3910Real-time Systems • Week 2, Class 2 • Return stuff, New HW Assignment! • Quiz! (Possibly with review) • Ohm’s Law • Kirkhoff’s Current Law • Switches • Using/reading an oscilloscope • Frequency / Period • Signals • Square, Sine, Saw-tooth, Random • Pulse Width Modulation (PWM) SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling, Some from Dr. Hornick, etc.
Waveform Terminology • Amplitude • Peak-to-peak voltage • Peak voltage (alternative defs) • Period • Frequency (review) SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Sketching & Listening to Waveforms • Sine wave • Square wave • Sawtooth wave(s) • Random wave • Efffect of changing • Amplitude • Frequency • Phase (time shift) On sound! SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Technical Goals • How does one control the speed of a motor? • How does one change the brightness of a light-bulb? SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Pulse-Width-Modulation… in traffic SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Pulse-width modulation terminology • Determine the duty cycle (D) • Multiply the duty cycle by the peak voltage (Vp) SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
In-class exercise • How can you control the brightness of an LED, using tools we have discussed so far? • How would you accomplish this if you went into lab right now? SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Advantages of Pulse-Width Modulation • Click to add text SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling
Power of a signal (If time) • P = IV • I = V/R • P = … • Let R = 1 (Ohm) • What is the instantaneous power of a sinusoid? • What is the average power of a sinusoid? • What is the average power of a PWM signal? SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling