Brief description about Flip Flops.

1. Electrónica Digital
Eduardo Emanuel Tovias
Garza
Engineer Aurelio García
Técnico
Mecatrónica Área
Automatización
30th November 2020 - Matamoros,
Tamaulipas

2. SEPARATOR:
FLIP - FLOPS

3. FLIP – FLOPS Description

4. Flip – Flops Description
As flip-flops are bistable devices, these sequential circuits
are sometimes called “latches” because their outputs are
locked or latched onto their input state until there is
another change to its input condition.
The interconnection of digital logic gates to produce a
memory device leads to applications such as switch
debounce circuits, shift registers and counters, etc. Also,
memory elements made from bistable latches form the
basis of accumulators and registers on which a computer,
or micro-controller, does its complex arithmetic.

5. Flip – Flops Description
In the parlance of electronics, a flip-flop is a special type of
gated latch. The difference between a flip-flop and a gated
latch is that in a flip-flop, the inputs aren’t enabled merely by
the presence of a HIGH signal on the CLOCK input.
Instead, the inputs are enabled by the transition of the
CLOCK input. Thus, at the moment that the clock input
transitions from low to high, the inputs are briefly enabled.
Once the clock stabilizes at the HIGH setting, the output state
of the flip-flop is latched until the next clock pulse.
Flip-flops are often said to be edge-triggered because it’s the
edge of the clock signal that triggers the flip-flop. When used
in clock-driven computer circuits, edge-triggering is an
important characteristic because it helps circuit designers
maintain better control over the timing in circuits that contain
hundreds or perhaps thousands of flip-flops.
Initially, the clock input is LOW. The inverter causes the first input
to the NAND gate to be HIGH, while the second input is LOW.
Because the inputs aren’t both HIGH, the output from the NAND
gate at point 2 is HIGH.
The second inverter inverts the NAND gate output so the final
output from the circuit at point 3 is LOW, just like the clock input.
When the clock input goes high, the second input to the NAND
gate goes high immediately. However, it takes a few milliseconds
for the inverter to respond, so for those few milliseconds, the
output from the inverter is still HIGH.

6. Flip – Flops Description
Applications of Flip Flops
Registers are the devices which are meant to store
the data. As known, each flip-flop can store a single-
bit of information. This means that by cascading n
flip-flops, one can store n bits of information.
Counters are the digital circuits which are used to
count the number of events. These are nothing but a
series of flip-flops (JK or D or T) arranged in a definite
manner.
Frequency Divider consider a positive edge
triggered JK flip-flop whose inputs are tied-together
and driven high, in this state,
Flip Flop counter instance

7. SR Flip - Flop

8. SR Flip – Flop
The SR flip-flop, also known as a SR Latch, can be considered as one of the
most basic sequential logic circuit possible. This simple flip-flop is basically a
one-bit memory bistable device that has two inputs, one which will “SET”
the device (meaning the output = “1”), and is labelled S and one which will
“RESET” the device (meaning the output = “0”), labelled R.
Then the SR description stands for “Set-Reset”. The reset input resets the
flip-flop back to its original state with an output Q that will be either at a
logic level “1” or logic “0” depending upon this set/reset condition.
A basic NAND gate SR flip-flop circuit provides feedback from both of its
outputs back to its opposing inputs and is commonly used in memory
circuits to store a single data bit. Then the SR flip-flop has three
inputs, Set, Reset and its current output Q relating to it’s current state or
history.
The term “Flip-flop” relates to the actual operation of the device, as it can
be “flipped” into one logic Set state or “flopped” back into the opposing
logic Reset state.
Truth table of SR Flip Flop

9. JK Flip - Flop

10. D Flip – Flop
Thus this single input is called the “DATA” input. If this data input is held
HIGH the flip flop would be “SET” and when it is LOW the flip flop would
change and become “RESET”. However, this would be rather pointless since
the output of the flip flop would always change on every pulse applied to
this data input.
To avoid this an additional input called the “CLOCK” or “ENABLE” input is
used to isolate the data input from the flip flop’s latching circuitry after the
desired data has been stored. The effect is that D input condition is only
copied to the output Q when the clock input is active. This then forms the
basis of another sequential device called a D Flip Flop.
The “D flip flop” will store and output whatever logic level is applied to its
data terminal so long as the clock input is HIGH.
Once the clock input goes LOW the “set” and “reset” inputs of the flip-flop
are both held at logic level “1” so it will not change state and store whatever
data was present on its output before the clock transition occurred. In other
words the output is “latched” at either logic “0” or logic “1”.
Truth table of D Flip Flop

11. T Flip - Flop

12. T Flip – Flop
The name T flip-flop is termed from the nature of toggling operation. The
major applications of T flip-flop are counters and control circuits. T flip flop
is modified form of JK flip-flop making it to operate in toggling region.
Whenever the clock signal is LOW, the input is never going to affect the
output state. The clock has to be high for the inputs to get active. Thus, T
flip-flop is a controlled Bi-stable latch where the clock signal is the control
signal. Thus, the output has two stable states based on the inputs which
have been discussed below.
The T flip flop is the modified form of JK flip flop. The Q and Q’ represents
the output states of the flip-flop. According to the table, based on the input
the output changes its state. But, the important thing to consider is all these
can occur only in the presence of the clock signal. This, works unlike SR flip
Flop & JK flip-flop for the complimentary inputs. This only has the toggling
function.
Truth table of T Flip Flop

13. Counter using Flip - Flop

14. Counter using Flip – Flop
Asynchronous Counters
If the flip-flops do not receive the same clock
signal, then that counter is called
as Asynchronous counter.
The output of system clock is applied as clock
signal only to first flip-flop.
The remaining flip-flops receive the clock
signal from output of its previous stage flip-
flop. Hence, the outputs of all flip-flops do not
change affect at the same time.

15. Operation Counter using Flip - Flop

16. Operation Counter using Flip – Flop
This circuit with D Flip – Flop
Four-bit Asynchronous Up Counter

17. SEPARATOR:
MICROCOTROLLERS

18. Microcontroller
Description

19. Microcontroller Description
A microcontroller is an integrated circuit (IC) device used for controlling
other portions of an electronic system, usually via a microprocessor unit
(MPU), memory, and some peripherals. These devices are optimized for
embedded applications that require both processing functionality and agile,
responsive interaction with digital, analog, or electromechanical
components.
The most common way to refer to this category of integrated circuits is
“microcontroller" but the abbreviation “MCU” is used interchangeably as
it stands for “microcontroller unit”. You may also occasionally see “µC”
(where the Greek letter mu replaces “micro”).
“Microcontroller” is a well-chosen name because it emphasizes defining
characteristics of this product category. The prefix “micro” implies smallness
and the term "controller" here implies an enhanced ability to perform
control functions.
As stated above, this functionality is the result of combining a digital
processor and digital memory with additional hardware that is specifically
designed to help the microcontroller interact with other components.

20. Microcontroller vs Microprocessor
Microprocessor Microcontroller
CPU
The microprocessor has much more
computing power, so it only performs its
functions with what it has (data) and its
algorithm or established program.
It is one of its main parts, which is
responsible for directing its operations.
RAM & ROM Memory They are external devices that
complement it for optimal operation.
It includes them in a single integrated
circuit.
Operation Velocity Faster Slow compared to a microprocessor
Size
The basic minimum configuration of a
Microprocessor is constituted by a
Microprocessor, a RAM memory, a ROM
memory, an address decoder, which
makes it a rather cumbersome circuit.
The Microcontroller includes all these
elements in a single Integrated Circuit,
which implies a great advantage in
several factors, such as, for example, the
reduction in the size of the printed
circuit due to the reduction of external
circuits.
Cost For the Microprocessor, the cost is very
high today.
The cost for a Microcontroller based
system is much lower.
Interference
They are more susceptible to
electromagnetic interference due to
their size and their external wiring which
makes them more prone to noise.
High level of integration reduces levels
of electromagnetic interference
Development time The development time of a
microprocessor is slow.
In contrast, that of a microcontroller is
fast.

21. Von – Neumann
Architecture

22. Von - Neumann Architecture
The von Neumann architecture also known as the von Neumann model or Princeton architecture
is a computer architecture based on a 1945 description by John von Neumann and others in the First
Draft of a Report on the EDVAC. That document describes a design architecture for an
electronic digital computer with these components:
•A processing unit that contains an arithmetic logic unit and processor registers
•A control unit that contains an instruction register and program counter
•Memory that stores data and instructions
•External mass storage
•Input and output mechanisms
The term "von Neumann architecture" has evolved to mean any stored-program computer in which
an instruction fetch and a data operation cannot occur at the same time because they share a
common bus. This is referred to as the von Neumann bottleneck and often limits the performance of
the system.
The design of a von Neumann architecture machine is simpler than a Harvard architecture machine—
which is also a stored-program system but has one dedicated set of address and data buses for
reading and writing to memory, and another set of address and data buses to fetch instructions.
A stored-program digital computer keeps both program instructions and data in read–write, random-
access memory (RAM).
Stored-program computers were an advancement over the program-controlled computers of the
1940s, such as the Colossus and the ENIAC. Those were programmed by setting switches and
inserting patch cables to route data and control signals between various functional units. The vast
majority of modern computers use the same memory for both data and program instructions, but
have caches between the CPU and memory, and, for the caches closest to the CPU, have separate
caches for instructions and data, so that most instruction and data fetches use separate buses (split
cache architecture).

23. Harvard
Architecture

24. Harvard Architecture
he Harvard architecture is a computer architecture with separate storage
and signal pathways for instructions and data. It contrasts with the von
Neumann architecture, where program instructions and data share the same
memory and pathways.
The term originated from the Harvard Mark I relay-based computer, which
stored instructions on punched tape (24 bits wide) and data in electro-
mechanical counters. These early machines had data storage entirely
contained within the central processing unit, and provided no access to the
instruction storage as data. Programs needed to be loaded by an operator;
the processor could not initialize itself.
Modern processors appear to the user to be von Neumann machines, with
the program code stored in the same main memory as the data. For
performance reasons, internally and largely invisible to the user, most
designs have separate processor caches for the instructions and data, with
separate pathways into the processor for each. This is one form of what is
known as the modified Harvard architecture.

25. Von – Neumann Architecture
vs
Harvard Architecture

26. Von – Neumman Architecture vs Harvard architecture
Von Neumann Harvard
It is a theorical design based on the
stored – program computer concept
It is a modern computer
architecture based on the Harvard
Mark I relay - based computer
model
It uses same physical memory
anddress for instructions and data
It uses separate memory addresses
for instructions and data
Processor needs two clock cycles to
execute an instruction
Processor needs one cycle to
complete an instruction
Simpler control unit design and
development of one is cheaper and
faster
Control unit for two buses is more
complicated witch adds to
development cost
Data transfers and instrucción
fetches cannot be porformed
simultaneously
Data transfers and instruction
fetches can be performed at the
same time
Used in personal computers, laptops
and workstations
Used in microcontrollers and signal
process

27. PIC 16F628A

28. Pic 16F628A

29. Pic 16F628A

30. Microcontroller Programming Hardware
Microchip’s PICkit 3

31. Microcontroller Programming procedure

32. Microcontroller Programming procedure
This is de IDE
software with
code, this is used
for to turn on and
turn off a LED