1)What is an Asynchronous Counter?
In an asynchronous counter, the flip-flop output transition serves as a source for triggering other flip-flops. In other words, the Clock Pulse intputs of all flip-flops (except the first) are triggered not by the incoming pulses but rather by the transition that occurs in other flip-flops.
2)What is a Ripple Counter?
A ripple counter is nothing but an asynchronous counter, consists of a series connection of complementing flip-flops (T or JK type), with the output of each flip-flop connected to the Clock Pulses input of the next higher-order flip-flop. The flip-flop holding least significant bit (LSB) receives the incoming clock pulse.
3)What is a Binary Down-Counter?
A counter that follows the binary sequence is called a binary counter. A Binary Couter with a reverse count is called a Binary Down-Counter.
4)What is a BCD Ripple Counter or BCD Counter?
A decimal counter follows a sequence of ten states and return to 0(zero) after the count of 9 (nine). Such a counter must have at least four flip-flops to represent each decimal digit, since a decimal digit is represented by a binary code used to represent a decimal digit.