1. Digital and Analog Quantities

2. Graph of an analog quantity (temperature versus time).

3. Graph of an analog quantity (temperature versus time).

4. Types of electronic devices or instruments:
Analog
Digital
Combination analog and digital

5. Audio Signal Amplification

6. Analog Reproduction of Music Audio Signal

7. Simplified basic block diagram for a tablet-counting and bottling control system

8. Advantages of digital circuits
Fast process time.
Fast transmission time.
Large storage capability.

9. Advantages of digital circuits
The conventional numbering system uses ten digits: 0,1, 2, 3, 4, 5, 6, 7, 8, and 9.
The binary numbering system uses just two digits: 0 and 1.

10. Binary Digits & Logic Levels
The two binary digits are designated 0 and 1
They can also be called LOW and HIGH,
where LOW = 0 and HIGH = 1

11. Digital Pulse Binary values are also represented
by voltage levels by voltage levels

12. Major Parts (Important Items) of a Digital Pulse
Base line
Amplitude
Rise time (tr)
Pulse width (tw)
Fall time (tf)

13. Nonideal Pulse
A nonideal pulse typical of those found in actual digital circuits tw
Pulse width
Amplitude
= 5.0 V
4.5 V
2.5 V
0.5 V
0.0 V tr
Rise
time tf
Fall
5.0 V

14. Information on Important Items
Rise time, tr - time required to go from LOW to HIGH.
Fall time, tf - time required to go from HIGH to LOW.
Amplitude – height measured between HIGH and LOW (or vice versa). Measurement for rise and fall time usually made within 10% to 90% of pulse amplitude.
Pulse width, tw - duration of pulse, measured at 50% points on the rising and falling edges.

15. Logic level ranges of voltage for a digital circuit.

16. TTL input and output voltage specifications
Input or output voltages that fall within the shaded region of Figure below are undefined voltages and cannot be distinguished as a logic LOW or logic HIGH by the IC’s circuitry.
LOGIC 0
Invalid
input voltage
LOGIC 1
0 V
0.8 V
2.0 V
5.0 V
(a)
TTL input (a) and output (b) voltage specifications
(b)
0.4 V
2.4 V
output voltage

17. Digital Waveforms tw = pulse width T = period of the waveform
f = frequency of the waveform

18. Digital Waveforms characteristics
A) Periodic Square Wave (repeating the same waveform at a fixed interval, called period (T))
B) Nonperiodic Square Wave (opposite to periodic, where the waveform does not repeat itself at a fixed interval)

19. Digital Waveforms Carry Binary Information

20. Clock and Timing Diagram
Clock –a basic timing waveform that is used to synchronize all waveforms in digital systems
Must be periodic!!!
Used to synchronize all waveforms in digital systems
Each interval between pulses in clock equals the time for one bit
It, itself does not carry any information
Timing diagram –a graph of digital waveforms showing the actual time relationship of two or more waveforms, and how each waveform changes in relation to the others

21. Timing Diagram: A Graph of Digital Waveforms

22. Serial Transfer of Binary Data.
Data are transferred in serial form from one point to another
Serial transfer of 8 bits data from computer to modem. t0 to t1 is first.
Slow. Why??–The data have to transferred one by one
Advantage:–Requires only one line

23. Parallel Transfer of Binary Data
Data are transferred in parallel form from one point to another
During transfer, all the bits in a group are sent out on separate lines simultaneously
Fast. Why??
– A few bits can be sent at one time
Disadvantage:
– Requires a few lines

24. Parallel Transfer of Binary Data (Cont.)
Parallel transfer of 8 bits of binary data from computer to printer. The beginning time is t0.

25. Fixed Function Integrated Circuits I
Monolithic – all components on a single chip –diode, transistor, resistor, capacitor.
Fixed-function logic – logic function have been fixed by the manufacturer. Need to refer spec sheet before using it / cannot be changed.
Opposite of fixed function = Programmable Logic Devices (PLDs)
Programmable logic – logic function can be changed based on the program that we write into the IC.

26. Fixed Function Integrated Circuits I (Cont.)
Cutaway view of one type of fixed-function IC package showing the chip mounted inside, with connection to input an output pins.

27. Fixed Function Integrated Circuits II
Examples of through-hole and surface-mounted devices. The DIP is larger than the SOIC with the same number of leads. This particular DIP is approximately 0.785in. long, and the SOIC is approximately in. long.

28. Fixed Function Integrated Circuits II (Cont.)
Flat pack with straight leads

29. Fixed Function Integrated Circuits III
Pin 1 always marked by an identifier like small dot, a notch, or beveled edge

30. IC Packages DIP (Dual In Line) –the most common.
SMT (Surface Mount Technology) – eg. Small outline integrated circuit (SOIC), PLCC (Plastic leaded chip carrier), LCCC (Leadless ceramic chip carrier).
Others: SSOP, TSSOP and TVSOP

31. Complexity Classification for Fixed-Function ICs
SSI (Small-scale integration) – 10 gates
MSI (Medium-scale integration) – gates
LSI (Large-scale integration) – ,000 gates
VLSI (Very large-scale integration) –10, ,000 gates
ULSI (Ultra large-scale integration) – >100,000 gates

32. Digital Logic Families
The two most widely used logic families are TTL, transistor-transistor logic, and CMOS, complementary metal-oxide semiconductor.
TTL had been the leading IC family in the small-scale and medium-scale integration categories until its leading position was challenged by the CMOS family.
The CMOS family belongs to the category of unipolar digital ICs because it uses p- and n-channel MOSFETs as the main circuit element.