Ultra-low-voltage processor

Class of microprocessor

Ultra-low-voltage processors (ULV processors) are a class of microprocessor that are deliberately underclocked to consume less power (typically 17 W or below), at the expense of performance.

These processors are commonly used in subnotebooks, netbooks, ultraportables and embedded devices, where low heat dissipation and long battery life are required.^[1]

Notable examples

Intel Atom – Up to 2.0 GHz at 2.4 W (Z550)
Intel Pentium M – Up to 1.3 GHz at 5 W (ULV 773)
Intel Core 2 Solo – Up to 1.4 GHz at 5.5 W (SU3500)
Intel Core Solo – Up to 1.3 GHz at 5.5 W (U1500)
Intel Celeron M – Up to 1.2 GHz at 5.5 W (ULV 722)
VIA Eden – Up to 1.5 GHz at 7.5 W
VIA C7 – Up to 1.6 GHz at 8 W (C7-M ULV)
VIA Nano – Up to 1.3 GHz at 8 W (U2250)
AMD Athlon Neo – Up to 1 GHz at 8 W (Sempron 200U)
AMD Geode – Up to 1 GHz at 9 W (NX 1500)
Intel Core 2 Duo – Up to 1.3 GHz at 10 W (U7700)
Intel Core i3/i5/i7 – Up to 1.5 GHz at 13 W (Core i7 3689Y)
AMD A Series – Up to 3.2 GHz at 15 W (A10-7300P)

References

^ "The choices for thin, low-cost ULV laptops expand". ZDNET. Retrieved 2023-01-06.

Processor technologies

Models

Architecture

Instruction set
architectures

Types	Orthogonal instruction set CISC RISC Application-specific EDGE TRIPS VLIW EPIC MISC OISC NISC ZISC VISC architecture Quantum computing Comparison Addressing modes
Instruction sets	Motorola 68000 series VAX PDP-11 x86 ARM Stanford MIPS MIPS MIPS-X Power POWER PowerPC Power ISA Clipper architecture SPARC SuperH DEC Alpha ETRAX CRIS M32R Unicore Itanium OpenRISC RISC-V MicroBlaze LMC System/3x0 S/360 S/370 S/390 z/Architecture Tilera ISA VISC architecture Epiphany architecture Others

Execution

Instruction pipelining	Pipeline stall Operand forwarding Classic RISC pipeline
Hazards	Data dependency Structural Control False sharing
Out-of-order	Scoreboarding Tomasulo's algorithm Reservation station Re-order buffer Register renaming Wide-issue
Speculative	Branch prediction Memory dependence prediction

Parallelism

Level	Bit Bit-serial Word Instruction Pipelining Scalar Superscalar Task Thread Process Data Vector Memory Distributed
Multithreading	Temporal Simultaneous Hyperthreading Simultaneous and heterogenous Speculative Preemptive Cooperative
Flynn's taxonomy	SISD SIMD Array processing (SIMT) Pipelined processing Associative processing SWAR MISD MIMD SPMD

Processor
performance

Transistor count
Instructions per cycle (IPC)
- Cycles per instruction (CPI)
Instructions per second (IPS)
Floating-point operations per second (FLOPS)
Transactions per second (TPS)
Synaptic updates per second (SUPS)
Performance per watt (PPW)
Cache performance metrics
Computer performance by orders of magnitude

Types

By application	Embedded system Microprocessor Microcontroller Mobile Ultra-low-voltage ASIP Soft microprocessor
Systems on chip	System on a chip (SoC) Multiprocessor (MPSoC) Cypress PSoC Network on a chip (NoC)
Hardware accelerators	Coprocessor AI accelerator Graphics processing unit (GPU) Image processor Vision processing unit (VPU) Physics processing unit (PPU) Digital signal processor (DSP) Tensor Processing Unit (TPU) Secure cryptoprocessor Network processor Baseband processor

Word size

Core count

Components

Functional units	Arithmetic logic unit (ALU) Address generation unit (AGU) Floating-point unit (FPU) Memory management unit (MMU) Load–store unit Translation lookaside buffer (TLB) Branch predictor Branch target predictor Integrated memory controller (IMC) Memory management unit Instruction decoder
Logic	Combinational Sequential Glue Logic gate Quantum Array
Registers	Processor register Status register Stack register Register file Memory buffer Memory address register Program counter
Control unit	Hardwired control unit Instruction unit Data buffer Write buffer Microcode ROM Counter
Datapath	Multiplexer Demultiplexer Adder Multiplier CPU Binary decoder Address decoder Sum-addressed decoder Barrel shifter
Circuitry	Integrated circuit 3D Mixed-signal Power management Boolean Digital Analog Quantum Switch