medium
2 min read
SRAM cells
SRAM Cell An SRAM cell is a fundamental building block of a semiconductor memory device. It acts as a bistable memory element, meaning its state can be swit...
Quick Actions
Insights
Difficultymedium
Reading Time2 min
SRAM Cell An SRAM cell is a fundamental building block of a semiconductor memory device. It acts as a bistable memory element, meaning its state can be swit...
SRAM Cell
An SRAM cell is a fundamental building block of a semiconductor memory device. It acts as a bistable memory element, meaning its state can be switched between two distinct values (1 and 0) under the control of a digital input signal.
Structure:
An SRAM cell consists of two transistors, called transistors A and B, connected to a capacitor.
The capacitor acts as a charge storage element, and the transistors control the flow of current between them.
By varying the voltage levels applied to the gate terminals of the transistors, the cell can be programmed to either a 1 or a 0 state.
Operation:
When a voltage is applied to the input control terminal (address pin), it sets the charge on the capacitor.
The charge remains on the capacitor as long as the input voltage remains high.
When the input voltage is removed, the charge leaks off the capacitor, and the cell goes back to its original state.
The cell can also be read out by applying a voltage to the output control terminal (data bus). If the input voltage is high, the cell will output a 1, indicating a 1 state. If the input voltage is low, the cell will output a 0, indicating a 0 state.
Advantages:
SRAM cells are highly compact and have a high density of storage bits.
They are relatively fast to access, with access times typically in the range of 10-20 nanoseconds.
They are reliable and have a long operational life.
Example:
An SRAM cell can be used to store a single bit of information. For example, a memory chip that contains hundreds of SRAM cells can be used to store a single byte of data. By addressing the cells in a specific order, we can read and write data to the memory chip