Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
One of the simplest circuits is the asynchronous or ' ripple' counter. Below is shown the circuit diagram of a simple 3 stage ripple counter.
The operation of this circuit is based on the fact that the truth table for the JK flip flop is only valid if the clock waveform is falling, i.e. 1->0. Assume the outputs are all zero, the flip flops will not change until the clock on each flip flop falls. The clock in waveform has just fallen ,since the JKa inputs are logic '1' the device will toggle and the output will invert i.e. Qa=1. Flip flop B will not change because the clock waveform on B has risen (0->1) and these devices only functions on a falling edge. The clock in waveform has fallen again, so Qa toggles again (i.e. Qa =0), this has just produced a falling clock on JKb and Qb toggles (i.e. Qab=1) .The device has just counted from 000-> 001->010.
The circuit is called a ripple counter because the clock pulse is slowly rippling through the JK's, hence asynchronous (Not at the same time!) .The limitations of the asynchronous counter is the speed of operation. A rough formula for the maximum speed is when the clock changes before the output changes i.e. F = 1 / n x propagation delay where n = number of stages, propagation delay of one JK
A better technique is to use a synchronous design where all the JK are clocked together so the maximum frequency is only limited by the propagation delay of 1 JK.
The circuit appears to be complex in design, however it is easily realised by using state diagrams. The maximum frequency of operation is again roughly calculated by considering the frequency at which the output just changes before the clock in changes. F = 1/ Propagation delay
Q. Write a control word for counter 1 of 8253 / 8254 that selects following options: load least significant byte only, mode 5 of operation and binary counting. Then write an inst
what is the full design for 16 logic microoperations
Magnetic circuits To see how this is used in practice, consider a coil of N turns wound onto a closed ring shaped former with a very high (note: r (steel) = 200
What is ideal and real sources? Source conversion? Nodal voltage method for d.c circuit?
Give four examples of natural insulating materials. Illustrations of the natural insulating materials are rubber, cotton, wood and mica.
Inference Rules of Explanation system How an Explanation System might work where questions like how or why are dealt with. Inference Rules use an if-statement and a then-statem
Equivalent Circuit of a DC Machine A review of the material presented with regard to elementary direct-current machines can be helpful at this stage to recall the principles of
series and parallel circuit
circuit diagrame
Q. Why FET is called a voltage-controlled device? Why its input resistance is high? In the case of a FET the output current ID is a function of the voltage VGS applied to the i
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd