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What is a keeper circuit?

What is a keeper circuit?

Keeper circuits are designed to assist in “keeping” the evaluate node charged High if it is suppose to evaluate High. Therefore, they need to be strong enough to resist noise, leakage, etc. that would otherwise cause the node to errantly discharge to a Low value.

What is bus in logic circuit?

Bus: a group of wires carrying a set of related signals from one place to another in a circuit. For example, a data bus would carry the 16 bits of a word on 16 separate wires, from the RAM to/from the CPU.

How to avoid monotonicity problem in dynamic CMOS?

To avoid this problem, dynamic gates must obey the MONOTONICITY rule: all inputs to dynamic gates should make only low to high transi- tions while the gates are evaluating. Inputs must be “monotonically rising,” meaning they can stay low, stay high, or may rise, but may not fall.

Which network is there between evaluate and precharge transistor?

The PDN (pull-down network) is constructed exactly as in complementary CMOS. The operation of this circuit is divided into two major phases: precharge and evaluation, with the mode of operation determined by the clock signal CLK.

What is a bus keeper?

A bus-holder (or Bus-keeper) is a weak latch circuit which holds last value on a tri-state bus.

Which technology is used for super buffers?

The term “super buffer” originates from silicon NMOS technology, and is used in silicon NMOS technology to describe a driver circuit that is approximately symmetrical in its capability of sourcing and sinking charge into a capacitive load.

Is bus a machine?

Explanation: though we often tell it a vehicle but it’s made up of sets of machines and electric wires which helps it to run. Like the engines of bus are connected with several wires which helps in the procedure of inserting petrol.

Why is monotonicity important?

If the analog output decreases at any point during the input sequence, a DAC is said to be non-monotonic. Monotonicity is an important characteristic in many communications applications in which DACs are used. Such applications can function in the presence of nonlinearity , but not in the presence of non-monotonicity.

Which logic gate is faster?

Emitter-coupled-logic (ECL) is a BJT logic family that is generally considered the fastest logic available.

What is precharge logic?

Description. Precharge logic is used by a variety of industries in applications where processor speed is the primary goal, such as VLSI (very large systems integration) applications. Also called dynamic logic, this type of design uses a clock to synchronize instructions in circuits.

What is the use of buffer in VLSI?

A digital buffer (or a voltage buffer) is an electronic circuit element used to isolate an input from an output. The buffer’s output state mirrors the input state. The buffer’s input impedance is high….Inverting tri-state digital buffer.

Data Input Control Input Output
0 1 1
1 1 0

What can be introduced to reduce the latch up effect?

What can be introduced to reduce the latch-up effect? Explanation: The introduction of guard rings can reduce the effect of latch-up problem. Guard rings are diffusions which decouple the parasitic bipolar transistors.

What is meant by monotonicity?

the condition of being unchanging or unvarying in tone.

What is Nora logic?

NORA logic is constructed of cascaded nMOS and pMOS dy- namic logic networks that end on latches, as it is shown in Fig. 1. A clock signal CLK and its complement CLKB are uti- lized for the circuit operation which is divided in two phases, the precharge and the evaluation.

What is static CMOS?

Concept A static CMOS gate is a combination of two networks, called the pull-up network (PUN) and the pull-down network(PDN). The figure shows a generic N input logic gate where all inputs are distributed to both the pull-up and pull-down networks.

Which is faster CMOS or TTL?

TTL chips are generally faster than CMOS gates (but see ACT series), however there are two logic technologies faster than TTL-Emitter-coupled logic (ECL) and gallium arsenide (GaAs). These chips come at considerable cost in power consumption and ease of interface to other logic families.