Digital Electronics NUMBER SYSTEM BINARY CODES BOOLEAN ALGEBRA K MAPS COMBINATIONAL CKT SEQUENTIAL CIRCUITS INTRODUCTION CLOCK BISTABLE MULTIVIBRATOR DERIVATION of FLIPFLOP circuit RS FLIPFLOP RS FLIPFLOP(NAND IMPLEMENTATION) R'S' FLIPFLOP Clocking RS LATCH Other LATCHes Timing problem in LATCHES ASYNCHRONUS INPUTS Parameters of CLOCK pulse QUESTIONS(LATCH using MUX) EDGE SENSITIVE LATCH (i.e. FLIPFLOP) MASTER SLAVE FF D FF USING MUX TIMING PARAMETERS OF FF CHARACTERISTIC EQUATIONS OF FFs EXCITATION TABLES OF FF CONVERSION OF 1 FF TO OTHER FF as 1bit MEMORY CELL REGISTERS SHIFT REGISTERS RING COUNTER JOHNSON COUNTER QUESTION(Serial Data transfer) ASYNCHRONOUS COUNTERS RIPPLE COUNTER COUNTER other than MOD-2n Designing COUNTER Using K-MAPS QUESTION(MOD 6 counter) QUESTION(Counter design) DOWN COUNTER QUESTION(Counter design) GLITCH SYNCHRONOUS COUNTER COMPARISON B/W SYNC. & ASYNC. COUNTERS CLOCK SKEW QUESTION(Maximum frequency question) QUESTION(Maximum frequency question) MORE QUESTIONS TIMING CIRCUITS

BISTABLE MULTIVIBRATOR

FLIP-FLOP is another name of Bi-stable Multi-vibrator. A flip-flop is the basic element of sequential circuit. It has the capability of storing 1 bit. The circuit of the Bi-stable Multi- vibrator using transistors is as follow:

The two transistors are used to store a single bit and they can hold data without external assistance as far as power is supplied to the circuit. If Q is high we get high as an input to the transistor T1 and hence Q bar is low and as Q bar is low we get LOW as input to transistor T2 and hence Q is HIGH. We can see how output is maintained by the circuit itself. So we don’t need t refresh the circuit again and again.