integrated circuit design Integrated circuit design, semiconductor design, chip design or IC design, is a sub-field of electronics engineering, encompassing the particular Boolean logic, logic and circuit design techniques required to design integrated circuits (ICs). A ...

, static core generally refers to a

microprocessor A microprocessor is a computer processor (computing), processor for which the data processing logic and control is included on a single integrated circuit (IC), or a small number of ICs. The microprocessor contains the arithmetic, logic, a ...

(MPU) entirely implemented in static logic. A static core MPU may be halted by stopping the system clock oscillator that is driving it, maintaining its state and resume processing at the point where it was stopped when the clock signal is restarted, as long as power continues to be applied. Static core MPUs are fabricated in the

CMOS Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss ", , ) is a type of MOSFET, metal–oxide–semiconductor field-effect transistor (MOSFET) semiconductor device fabrication, fabrication process that uses complementary an ...

process and hence consume very little power when the clock is stopped, making them useful in designs in which the MPU remains in standby mode until needed and minimal loading of the power source (often a battery) is desirable during standby. In comparison, dynamic core microprocessor designs, those without a static core, only refresh and present valid outputs on their pins during specific periods of the clock cycle. If the clock is slowed, or stopped, the charge on the pin leaks out of the

capacitor In electrical engineering, a capacitor is a device that stores electrical energy by accumulating electric charges on two closely spaced surfaces that are insulated from each other. The capacitor was originally known as the condenser, a term st ...

s over time, quickly moving to the default state and no longer being valid. Dynamic designs have to run within a set range of clock frequencies to avoid this problem. Static core microprocessors include the RCA 1802, Intel 80386EX, WDC W65C02S, WDC W65C816S and Freescale 683XX family. Many

low-power electronics Low-power electronics are electronics designed to consume less electrical power than usual, often at some expense. For example, notebook processors usually consume less power than their desktop counterparts, at the expense of computer perform ...

systems are designed as fully static systems—such as, for example, the Psion Organiser, the

TRS-80 Model 100 The TRS-80 Model 100 is a Notebook form factor, notebook-sized portable computer introduced in April 1983. It was the first commercially successful notebook computer, as well as one of the first notebook computers ever released. It features a k ...

, and the Galileo spacecraft. In such a fully static system, the processor has a static core and data is stored in

static RAM Static random-access memory (static RAM or SRAM) is a type of random-access memory (RAM) that uses latching circuitry (flip-flop) to store each bit. SRAM is volatile memory; data is lost when power is removed. The ''static'' qualifier differ ...

, rather than dynamic RAM. Such design features allow the entire system to be "paused" indefinitely in a low power state, and then instantly resumed when needed. Richard Murray
"PocketBook II hardware"

References

See also