Digital Design Lab
ENG. GHADIR AL JARO
Objectives:
The purpose of this experiment is to be familiar with the lab equipment available for
your use.
The main piece of equipment you will use in this lab is the trainer kit. Its front panel
is divided into several sections that you will need to become familiar with.
The main trainer kit:
Digital Design Lab
ENG. GHADIR AL JARO
Digital Design Lab
ENG. GHADIR AL JARO
KL-300 Main Unit
(1)&(2) Fixed & Variable DC
Voltage values: +5V, -5V, +12V and -12V
Power Supply
Voltage range: +1.5V ~ +15V, -1.5V ~ -15V
(4) Variable Clock
Generator
Six frequency ranges:
1Hz to 10Hz
10Hz to 100Hz
100Hz to 1kHz
1kHz to 10kHz
10kHz to 100kHz
100kHz to 1MHz
Output level: independent and simultaneous TTL and CMOS, CMOS
output range adjustable from +1.5V to +15V. Fanout: 10 TTL loads
(5) Standard Frequency
Generator
Preset frequencies:
1Hz, 50/60Hz, 1MHz, Output level: independent and simultaneous TTL
and CMOS, CMOS output range adjustable from +1.5V to +15V Fanout: 10
TTL loads
(6) &(7) Data Switches
Two 8-bit DIP switches giving 16-bit TTL level output
Four toggle switches, each with debounce circuit, TTL and CMOS outputs
Fanout: 10 TTL loads
(8) Pulser Switches
Two sets, each having debounced TTL and CMOS, Q and /Q outputs
Fanout: 10 TTL loads
(9) Thumbwheel Switches
Two-digit, BCD code output, common point input
(10)Seven-Segment
Displays
Four sets of independent 7-segment displays, with BCD, 7-segment
decoder/driver and decimal point input terminal, input with 8-4-2-1 code
(11)Logic Indicators
16 sets of independent LEDs, indicating high and low logic states Input
impedance: <100kW
(12)Speaker
8W, 0.25W speaker with driver circuit
(13)Logic Probe
TTL and CMOS level, 3mm LED displays indicate high and low logic states
(14)Removable
Breadboard
1680 interconnected tie points, accepting all DIP devices, components
with leads and solid wires of AWG #22-30 (0.3mm to 0.8mm)
Digital Design Lab
ENG. GHADIR AL JARO
Integrated Circuits (Chips):
Integrated Circuits are usually called ICs or chips. They are complex circuits which
have been etched onto tiny chips of semiconductor (silicon). The chip is packaged in
a plastic holder with pins spaced on a 0.1" (2.54mm) grid which will fit the holes on
strip board and breadboards. Very fine wires inside the
package link the chip to the pins. The pins are numbered
anti-clockwise around the IC (chip) starting near the notch
or dot. The diagram shows the numbering for 8-pin and
14-pin ICs, but the principle is the same for all sizes.
Each IC has a different number on its cover, and using this number data sheets are
available to describe the function of certain IC and all of its other properties. For
example the IC 74LS00 is a quadratic two input NAND gate and the 7402 NOR
gates.
You will find that some of the ICs that we use are so-called "quad packs", meaning
that each contain four independent gates. We will only need to measure one of the
gates in each IC. ICs are classified into logic families according to their internal
digital design, two main classes of these families that will be used in this lab are TTL
and CMOS
.
Digital Design Lab
ENG. GHADIR AL JARO
Breadboard Description:
The breadboard has 8 sets of rows, consisting of 25 holes that are horizontally
interconnected, and groups of columns, consisting of 5 holes that are vertically
interconnected. The rows and columns are used to hold chips and wires, and
interconnect them. The connection pattern used in the breadboard is shown in the
following figures.
The top and bottom rows can be used to distribute +5V DC and ground to the ICs.
Note that the top and bottom “bus” rows have a break in the very middle! If you
want a power or ground bus to run the length of the breadboard, you must insert a
jumper in the middle of the row to join the two half rows together.
Digital Design Lab
ENG. GHADIR AL JARO
This makes your wiring less crowded, and makes it easy to see power and ground
connections.
Good wiring
Bad wiring.
Data switches:
In order to verify the operation of a gate it is necessary
to measure the output for all possible combinations of
inputs. We will use a 5 V DC power supply and a single
ground connection to power the IC. The logic switches,
are used to provide both a logic 0 output and logic 1
output to drive the circuits you will design and build.
They provide a voltage of zero volts (ground) for logic
0, and either +5V or other voltage settings for logic 1.It is important to note that for
logic inputs we must use either 5 V or 0 V . We cannot simply let an input float if
we want 0 V (float inputs are considered to be of logic 1).
Digital Design Lab
ENG. GHADIR AL JARO
Logic Indicators:
You could use either the scope or an LED (light emitting diode) to observe the
output. In this lab, we will measure the output of the logic gate using an LED. When
using LEDs to observe the output of TTL logic, be sure to put them in series with
current-limiting resistors. This limits the maximum current to around 10mA and will
protect the output ports of the gates. Such a circuit is shown in the Figure below,
we can have the LED on either when the output is high or when it is low, depending
on which configuration we use.
There are two configurations for LED connection: 1. Common Cathode: where the
LED will turn ON when the output of logic 1 and OFF at logic 0. 2. Common Anode:
where the LED will turn OFF when the output of logic 1 and ON at logic 0. In fact,
we could also connect LEDs to the inputs to the gate as well. In such a case, we
could easily read the truth table for our logic gates.
Common Cathode configuration
Common Anode configuration