Electronic WorkBench (EWB)

Zahra Sadeghi

Electronic WorkBench(EWB)

Starting Workbench

• Drawing Area • workbench area where

the circuit is assembled.

It cannot be closed.

• Description Window • This is a text area which allows

descriptions to be attached to the

circuit design. Any text entered into this

area will be saved with the design. This window is normally closed.

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Description Window

Drawing area

Pulldown Menus

Equipment Shelf

Pa

rts

Bin

SimulationT imeParts Bin Store

Logic converter

It can be attached to a circuit to

• derive the truth table

• boolean expression the circuit embodies

• to produce a circuit from a truth table or boolean expression.

Deriving a Truth Table from a Circuit

• 1. Attach the input terminals of the logic converter to up to eight input

points in the circuit.

• 2. Connect the single output of the circuit to the output terminal on the

logic converter icon.

• 3. Click the Circuit to Truth Table button.

• The truth table for the circuit appears in the logic converter's display.

Entering and Converting a Truth Table Using the

Logic Converter

To construct a truth table:

1. Click the number of input channels you want, from A to H, across the top of the logic converter.

• The display area below the terminals fills up with the necessary combinations of ones and zeros to fulfill the input conditions. The values in the output column on the right are initially set to 0.

2. Edit the output column to specify the desired output for each input condition.

• To change an output value select it and type a new value:

1, 0 or x

• To convert a truth table to a

Boolean expression: • The Boolean expression will be displayed

at the bottom of the logic converter.

• To convert a truth table to a simplified Boolean

expression: • The simplification is performed by the Quine-McCluskey method, rather than the

more familiar Karnaugh mapping technique.

• To convert a Boolean expression to a circuit

• To see a circuit that fulfills the conditions of the

Boolean expression using only NAND gates

Example of logic converter

WORD GENERATOR

Entering Words in Word Generator

• left side: rows of 4-character hexadecimal numbers.

• range :from 0000 to FFFF(0 to 65535, in decimal).

Each horizontal row =a binary 16-bit word.

• When the word generator is activated, a row

of bits is sent in parallel to the corresponding

terminals at the bottom of the instrument.

• As the words are transmitted by the word generator,

the value of each bit appears in the circles

representing the output terminals at the bottom of the

instrument.

patterrn

Word generator

sends digital words or patterns

of bits into circuits.

inject the 16-bit words intoa circuit:

1.Step:To transmit one word

at a time into the circuit.

2. Burst:To send all words in

sequence.

3. Cycle: sends a continuous

stream of words that can be

stopped by clicking Cycle again,

or by pressing CTRL+T.

4.Breakpoint: to pause and restart the stream of words at a

specified word.

example

Logic analyzer

• Data is displayed as square waves over time

• The binary value of each bit in the current

word is displayed in the terminals on the left side

of the instrument face.

example

8 bit adder

Logic analyzer • The logic analyzer displays the levels of up to 16 digital signals

in a circuit

• To clear the logic analyzer's display, click Reset.

• To dump stored data when the logic analyzer is not triggered,

click Stop. If the logic analyzer is already triggered and

displaying data, Stop has no effec

Multimeter

• Use the multimeter

to measure AC or

DC voltage or current,

resistance between two

points in a circuit.

• Measures V, A, W,

dB , d.c., a.c.

Function generator • is a voltage source that

supplies sine, triangular or

square waves.

A realistic way to supply power

to a circuit.

• The positive terminal

(+) provides a waveform

in the positive direction

from the neutral common terminal. The negative terminal (-)

provides a waveform in the negative direction.