In
electronics
The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...
, pin-compatible devices are
electronic component
An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are n ...
s, generally
integrated circuits or
expansion card
In computing, an expansion card (also called an expansion board, adapter card, peripheral card or accessory card) is a printed circuit board that can be inserted into an electrical connector, or expansion slot (also referred to as a bus sl ...
s, sharing a common
footprint and with the same functions assigned or usable on the same
pins.
Pin compatibility is a property desired by
systems integrator
A systems integrator (or system integrator) is a person or company that specializes in bringing together component subsystems into a whole and ensuring that those subsystems function together, a practice known as system integration. They also sol ...
s as it allows a product to be updated without redesigning
printed circuit board
A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a laminated sandwich str ...
s, which can reduce costs and decrease
time to market.
Although devices which are pin-compatible share a common footprint, they are not necessarily electrically or thermally compatible. As a result, manufacturers often specify devices as being either ''pin-to-pin'' or ''drop-in'' compatible.
Pin-compatible devices are generally produced to allow upgrading within a single
product line
Product may refer to:
Business
* Product (business), an item that serves as a solution to a specific consumer problem.
* Product (project management), a deliverable or set of deliverables that contribute to a business solution
Mathematics
* Prod ...
, to allow
end-of-life devices to be replaced with newer equivalents, or to compete with the equivalent products of other manufacturers.
Pin-to-pin compatibility
''Pin-to-pin compatible'' devices share an assignment of functions to pins, but may have differing electrical characteristics (supply
voltage
Voltage, also known as electric pressure, electric tension, or (electric) potential difference, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge t ...
s, or
oscillator frequencies) or thermal characteristics (
TDPs,
reflow curves, or
temperature tolerances). As a result, their use in a system may require that portions of the system, such as its power delivery subsystem, be adapted to fit the new component.
A common example of pin-to-pin compatible devices which may not be electrically compatible are the
7400 series integrated circuits. The 7400 series devices have been produced on a number of different manufacturing processes, but have retained the same
pinout
In electronics, a pinout (sometimes written "pin-out") is a cross-reference between the contacts, or ''pins'', of an electrical connector or electronic component, and their functions. "Pinout" now supersedes the term "basing diagram" that was the s ...
s throughout. For example, all 7405 devices provide six
NOT gates (or inverters) but may have incompatible supply voltage tolerances.
* 7405 – Standard
TTL, 4.75–5.25 V.
* 74C05 –
CMOS, 4–15 V.
* 74LV05 – Low-voltage CMOS, 2.0–5.5 V.
In other cases, particularly with
computers, devices may be pin-to-pin compatible but made otherwise incompatible as a result of
market segmentation
In marketing, market segmentation is the process of dividing a broad consumer or business market, normally consisting of existing and potential customers, into sub-groups of consumers (known as ''segments'') based on some type of shared charact ...
. For example,
Intel Skylake desktop-class
Core and
Xeon E3v5 processors both use the
LGA 1151
LGA 1151, also known as Socket H4, zero insertion force flip-chip land grid array (LGA) socket for Intel desktop processors which comes in two distinct versions: the first revision which supports both Intel's Skylake and Kaby Lake CPUs ...
socket, but
motherboard
A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...
s using C230-series
chipset
In a computer system, a chipset is a set of electronic components in one or more integrated circuits known as a "Data Flow Management System" that manages the data flow between the processor, memory and peripherals. It is usually found on t ...
s will only be compatible with Xeon-branded processors, and will not work with Core-branded processors.
Drop-in compatibility
A ''drop-in compatible'' device is a device which may be swapped with another without need to make compensating alterations to the system the device was a part of. The device will have the same functions available on the same pins, and will be electrically and thermally compatible. Such devices may not be an exact match to the devices they can replace. For example, they may have a wider range of supply voltage or temperature tolerances.
Software compatibility
''Software-compatible'' devices are devices which are able to run the same software to produce the same results without the software having to be modified first.
Microcontroller
A microcontroller (MCU for ''microcontroller unit'', often also MC, UC, or μC) is a small computer on a single VLSI integrated circuit (IC) chip. A microcontroller contains one or more CPUs ( processor cores) along with memory and programma ...
s,
FPGA
A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturinghence the term ''Field-programmability, field-programmable''. The FPGA configuration is generally specifi ...
s, and other programmable devices may be pin-to-pin compatible from the perspective of the program on the device, but incompatible in terms of hardware. For example, the device may take the signal on pin X,
negate it, and output the result on pin Y. If the method of configuring a pin remains the same but the
package of the device (such as
TSSOP or
QFN) changes, the program will continue to function but the physical locations of the pins the program works with may change.
A device may also be pin-compatible while being software-incompatible. This may occur when the device uses a different
instruction set
In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called a ...
, or if the device has a
multiplexer
In electronics, a multiplexer (or mux; spelled sometimes as multiplexor), also known as a data selector, is a device that selects between several analog or digital input signals and forwards the selected input to a single output line. The sel ...
attached to a pin (which, for example, may allow the switching of the pin between being driven as
GPIO
A general-purpose input/output (GPIO) is an uncommitted digital signal pin on an integrated circuit or electronic circuit (e.g. MCUs/ MPUs ) board which may be used as an input or output, or both, and is controllable by software.
GPIOs have n ...
or by an
A/D) and that multiplexer selects, by default, a different input source than is selected on the device being replaced.
To ease the use of software-incompatible devices, manufacturers often provide
hardware abstraction layers. Examples of these include,
CMSIS for
ARM Cortex-M
The ARM Cortex-M is a group of 32-bit RISC ARM processor cores licensed by Arm Holdings. These cores are optimized for low-cost and energy-efficient integrated circuits, which have been embedded in tens of billions of consumer devices. Thou ...
processors and the now-deprecated
HAL
HAL may refer to:
Aviation
* Halali Airport (IATA airport code: HAL) Halali, Oshikoto, Namibia
* Hawaiian Airlines (ICAO airline code: HAL)
* HAL Airport, Bangalore, India
* Hindustan Aeronautics Limited an Indian aerospace manufacturer of fight ...
subsystem for
UNIX-like
A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-li ...
operating systems.
See also
*
7400 series integrated circuits
*
Programmable logic
*
Logic family
In computer engineering, a logic family is one of two related concepts:
* A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compat ...
*
Semiconductor packages
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...
External links
Giant Internet IC Master Database– A list of 74'xx series and other generic chip pinouts.
References
{{reflist, colwidth=30em
Integrated circuits
Interoperability