Static RAM (SRAM) and Dynamic RAM (DRAM)

Static RAM (SRAM) and Dynamic RAM (DRAM) are two commonly used types of random access memory in computer systems. While both types serve the same purpose of storing and retrieving data, they differ in terms of their construction and operation.

Static RAM (SRAM)
- SRAM is a type of RAM that uses flip-flops to store each bit of data.
- It is called "static" because the data remains stored as long as power is supplied to the memory.
- SRAM cells are typically constructed using transistors and are more complex compared to DRAM cells.

Dynamic RAM (DRAM)
- DRAM is a type of RAM that uses a capacitor to store each bit of data.
- It is called "dynamic" because the capacitors need to be constantly refreshed to retain the stored data.
- DRAM cells are simpler and require fewer components compared to SRAM cells.

Comparison of SRAM and DRAM Cells

SRAM Cell:
- A typical SRAM cell requires 6 transistors.
- The 6 transistors are organized in a flip-flop configuration.
- The transistors are used to create a latch that can store a single bit of data.
- The latch remains stable as long as power is supplied to the memory.

DRAM Cell:
- A typical DRAM cell requires 1 transistor along with capacitance.
- The transistor is used as a switch to control the flow of charge into the capacitor.
- The capacitance represents the storage element in a DRAM cell.
- The charge on the capacitor represents the stored data, and it needs to be refreshed periodically to prevent data loss.

Explanation of the Correct Answer
The correct answer is option 'A' which states that a typical dynamic RAM requires 1 transistor along with capacitance. This is because a DRAM cell consists of a single transistor that acts as a switch to control the flow of charge into the capacitor. The capacitance represents the storage element in a DRAM cell.

Unlike SRAM, DRAM cells require periodic refreshing to maintain the stored data. This is because the charge stored in the capacitor tends to leak away over time. By refreshing the charge, the data can be retained in the DRAM cell.

Therefore, the structure of a typical DRAM cell involves a single transistor and a capacitor, making option 'A' the correct answer.