DB14
4 Bit Binary Ripple Counter (Up-Down Counter)
Product Tutorial
Ver.1.1
Designed & Manufactured in India byAn ISO 9001:2008 company
Scientech Technologies Pvt. Ltd.
94, Electronic Complex, Pardesipura, Indore - 452 010 India,
+ 91-731 4211100, : info@scientech.bz , : www.ScientechWorld.com
DB14
4 Bit Binary Ripple Counter (Up-Down Counter)
DB14
Table of Contents
1.
Introduction
3
2.
Theory
4
3.
Experiment
6
Study of 4 Bit Binary Ripple Counter
·
Up counter
·
Down counter
4.
Data Sheet
10
5.
Warranty
11
6.
List of Accessories
11
2
DB14
Introduction
DB14 is a compact, ready to use 4 Bit Binary Ripple Counter (Up-Down Counter)
experiment board. This experiment board has been designed to study 4 Bit Binary
Ripple Up/Down Counter and verify truth table. It can be used as stand alone unit
with external power supply or can be used with Scientech Digital Lab Scientech
2611 which has built in power supply, pulse generator, pulser switches, 8 bits data
switches, logic probe, digital display, 8 bits LED display.
List of boards:
Model
Name
DB01
Logic Gates
DB02
Universal Gate- NAND/NOR
DB03
EX-OR Gate Implementation
DB04
Demorgan's Theorem
DB05
EX-OR Gate Application
DB06
Code Conversion (Binary to Gray & Gray to Binary)
DB07
Code Conversion (BCD to Excess-3 code)
DB08
Binary Adder -Subtractor
DB09
Encoder – Decoder
DB10
Multiplexer – Demultiplexer
DB11
Flip-Flops (R-S, D, J-K, T)
DB12
Shift Register (4 bit SIPO)
DB13
4 Bit Synchronous Binary Counter
DB16
Digital to Analog Converter (R-2R ladder)
DB15
BCD to 7- Segment Decoder
DB17
Event Counter
DB21
Fiber Optic Digital Link
DB22
Analog to digital converter (Counter Type)
DB27
Digital to Analog Converter (R-2R ladder)
DB28
Monostable Multivibrator
DB29
CMOS and Crystal Oscillator
DB30
Adder/ Subtracter (4-Bit/8-Bit)
DB31
Decoder/Demultiplexer
DB32
Modulo-N programmable counter
DB35
4 BIT Shift Register
………and many more
3
DB14
Theory
A sequential circuit that goes through a prescribed sequence of states upon the
application of input pulses is called a counter. A counter that follows the binary
sequence is called a binary counter. An n-bit binary counter consists of n flip-flops
and can count in binary from 0 to 2n-1. State transitions in clocked sequential circuits
occur during a clock pulse; the flip-flops remain in their present states if no pulse
occurs. Counters come in two categories viz Ripple counters and Synchronous
counters. In a ripple counter, the flip-flop output transition serves as a source (i.e
clock) for triggering other flip-flops. i.e. CP inputs of all flip-flops (except the first)
are triggered not by the incoming pulses but rather by transition that occurs in other
flip-flops. In a synchronous counter, the input pulses are applied to all CP inputs of
flip-flops.
4 Bit Binary Ripple UP/Down Counter:
A Binary Ripple up Counter as shown in figure 1 consists of a series connection of
complementing J-K flip-flops, with the normal output of each flip-flop connected to
the CP input of the next higher-order flip-flop. It will count from 0000 to 1111. The
LSB flip-flop receives the incoming count pulses. The lowest order bit Q0 must be
complemented with each count pulse. Every time Q0 goes from 1 to 0, it
complements Q1. Every time Q1 goes from 1 to 0. it complements Q2 and so on. The
flip-flop change one at a time in rapid succession, and the signal propagates through
the counter in a ripple fashion. Ripple counters are also called Asynchronous Counter.
Ripple
UP
Counter
Figure 1
4
DB14
In Binary Down Counter as shown in figure 2 complement output of each flip-flop is
connected to the CP input of the next higher-order flip-flop. It will count from 1111 to
0000. Lowest order bit must be complemented with every count pulse. Any other bit
in the sequence is complemented if its previous lower-order bit goes from 0 to 1.
Ripple
Down
Counter
Figure 2
If clock pulse of frequency f is applied to CP terminal of LSB flip-flop then output
frequency at Q0, Q1, Q2, Q3 will be f/2, f/4, f/8, f/16 as shown in Truth Table 2 SD is
set input which sets output of flip-flops to logic 1, when connected to logic 0 (Gnd).
CD is clear/reset input which resets or clears output when connected to logic 0. Q3 Q2
Q1 Q0 are outputs of flip-flops where Qo is LSB. CP is clock pulse input. It will trigger
flip-flops on negative edge i.e +5 V to 0 transition (1 ®0).
5
DB14
Experiment 1
Objective:
Study of 4 Bit Binary UP/Down Counter
Equipment Needed:
1.
Digital board of, DB14
2.
DC Power Supply +5 V.
3.
Oscilloscope, Digital Multimeter or Digital Lab Scientech 2611.
Logic diagram & Truth table:
(Logic 1 = +5V & Logic 0= Gnd)
Ripple Up/Down Counter
Figure 3
6
DB14
Truth Table for Figure 1
Q0 is LSB
Sr.
No.
Q to
CP
SD
CD
CP
Q3
Q2
Q1
Q0
0
short
1
0
1
0
0
0
0
1
short
1
1
1® 0
0
0
0
1
2
short
1
1
1® 0
0
0
1
0
3
short
1
1
1® 0
0
0
1
1
4
short
1
1
1® 0
0
1
0
0
5
short
1
1
1® 0
0
1
0
1
6
short
1
1
1® 0
0
1
1
0
7
short
1
1
1® 0
0
1
1
1
8
short
1
1
1® 0
1
0
0
0
9
short
1
1
1® 0
1
0
0
1
10
short
1
1
1® 0
1
0
1
0
11
short
1
1
1® 0
1
0
1
1
12
short
1
1
1® 0
1
1
0
0
13
Short
1
1
1® 0
1
1
0
1
14
short
1
1
1® 0
1
1
1
0
15
short
1
1
1® 0
1
1
1
1
7
DB14
Truth Table for Figure 2
Q0 is LSB
S. No.
Q’ to
CP
SD
CD
CP
Q3
Q2
Q1
QO
0
short
0
1
1
1
1
1
1
1
short
1
1
1® 0
1
1
1
0
2
short
1
1
1® 0
1
1
0
1
3
short
1
1
1® 0
1
1
0
0
4
short
1
1
1® 0
1
0
1
1
5
short
1
1
1® 0
1
0
1
0
6
short
1
1
1® 0
1
0
0
1
7
short
1
1
1® 0
1
0
0
0
8
short
1
1
1® 0
0
1
1
1
9
short
1
1
1® 0
0
1
1
0
10
short
1
1
1® 0
0
1
0
1
11
short
1
1
1® 0
0
1
0
0
12
short
1
1
1® 0
0
0
1
1
13
short
1
1
1® 0
0
0
1
0
14
short
1
1
1® 0
0
0
0
1
15
short
1
1
1® 0
0
0
0
0
8
DB14
Procedure:
·
Connect +5 V and ground to their indicated position on DB14 experiment board
from external DC power supply or from DC power block of Digital Lab
Scientech 2611.
·
Switch on the power supply.
UP counter:
1.
Connect normal output of flip-flop to CP input of next flip-flop.
2.
Connect logic 1(+5 V) to CP and SD input.
3.
Clear the outputs Q0-Q3 by connecting logic 0 (Gnd or 0V) to CD inputs of
figure 3.
4.
Observe output on multimeter or on LED display of Digital Lab Scientech
2611. It will be 0 0 0 0.
5.
Connect logic 1 to MCD and MS inputs.
6.
Give Logic 1 to 0 transition (+5 V to Gnd.) to CP input.
7.
Observe output on multimeter or on LED display of Digital Lab Scientech
2611. It will be 0 0 0 1.
8.
Repeat step 6 and observe output and verify truth table for figure 1.
Down counter:
9.
Connect complement output of flip-flop to CP input of next flip-flop.
10.
Connect logic 1 (+5 V) to CP and CD input.
11.
Set the outputs Q0-Q3 by connecting logic 0 (Gnd or 0V) to SD inputs figure 3.
12.
Observe output on multimeter or on LED display of Digital Lab Scientech
2611. It will be 1 1 1 1.
13.
Connect logic 1 to CD and SD inputs.
14.
Give Logic 1 to 0 transition (+5 V to Gnd) to CP input.
15.
Observe output on multimeter or on LED display of Digital Lab Scientech
2611. It will be 1 1 1 0.
16.
Repeat step 14 and observe output and verify truth table for figure 2.
17.
Connect clock pulse of 3 KHz to CP input and observe outputs on Oscilloscope.
9
DB14
Data Sheet
Dual J-K Flip Flop
7476
Note: Pull up resistance of 1 k is required in open collector ICs to
get output.
10
DB14
Warranty
1.
We guarantee this product against all manufacturing defects for 12 months from
the date of sale by us or through our dealers.
2.
The guarantee will become void, if
a. The product is not operated as per the instruction given in the Learning
Material.
b. The agreed payment terms and other conditions of sale are not followed.
c. The customer resells the instrument to another party.
d. Any attempt is made to service and modify the instrument.
3.
The non-working of the product is to be communicated to us immediately giving
full details of the complaints and defects noticed specifically mentioning the
type, serial number of the product and date of purchase etc.
4.
The repair work will be carried out, provided the product is dispatched securely
packed and insured. The transportation charges shall be borne by the customer.
Hope you enjoyed the Scientech Experience.
List of Accessories
1.
2 mm. Patch Cord (Red) 16”.................................................................... 1 No.
2.
2 mm Patch Cord (Black) 16” .................................................................. 1 No.
3.
2 mm Patch Cord (Blue) 16” ............................................................... 15 Nos.
11