Last revised: November 4, 2024
Reviewed by: Scott Orlosky, consulting engineer  

Integrated circuit (IC) interfaces are semiconductor chips that are used to control and manage the sharing of information between devices.

Types

IC interfaces support many different types of serial and wireless technologies.

• Serial technologies for IC interfaces include RS232, RS422, and RS485; serial 1-wire, serial 2-wire, and serial 3-wire; controller area network bus (CANbus); serial peripheral interface (SPI); system management bus (SMBus); universal serial bus (USB); and USB on-the-go (USB OTG) or USB 4.
• Wireless technologies for IC interfaces include code division multiple access (CDMA), wide band code division multiple access (WCDMA), wireless fidelity (Wi-Fi) or IEEE 802.11, worldwide interoperability for microwave access (WiMAX) or IEEE 802.16, wireless mesh (Wi-Mesh), and ZigBee or IEEE 802.15.4. Bluetooth chips also provide wireless connectivity in solution-on-chip (SoC) platforms that power short-range radio communication applications.
• Wireless IC interfaces are also described as using 4G or 5G technologies.
• 4G is the fourth generation of mobile communication technology, enabling faster internet speeds, improved connectivity, and enhanced multimedia experiences on mobile devices compared to its predecessor, 3G

• 5G is the fifth generation of mobile communication technology, designed to deliver significantly faster data speeds, lower latency, and greater connectivity. It supports advanced applications like IoT, augmented reality, and smart cities, revolutionizing how devices interact and communicate.
• IC interfaces also support other communications technologies. Choices include current mode logic (CML), gunning transceiverlogic (GTL), and gunning transceiver logic plus (GTLP); emitter coupling logic (ECL), positive ECL (PECL) voltage PECL (LVPEC); low-voltage differential signaling (LVDS), Bus LVDS (BLVDS)  multi-point LVDS (M-LVDS); digital visual interface (DVI) and high-definition media interface (HDMI); and digital subscriber line (DSL) and integrated services digital network (ISDN).

Features

In addition, IC interfaces may also use technologies such as:

• actuator-sensor interface (AS-i)
• Ethernet
• fiber channel
• IEEE 1394 or FireWire^® (Apple Computer)
• Microwire or PanelBus
• high-speed downlink packet access (HSDPA)
• inter-integrated circuit (I²C)
• infrared data access (IrDA)
• global positioning system (GPS)
• general packet radio service (GPRS)
• low-voltage CMOS (LVCMOS)
• synchronous optical network (SONET)
• subscriber identification modules (SIM)
• small computer systems interface (SCSI)
• VersaModule Eurocard bus (VMEbus)

Peripheral component interconnect (PCI), compact PCI (cPCI), and PCI Express (PCIe) IC interfaces are also available.

Specifications 

Performance specifications for IC interfaces include supply voltage, data rate, operating current, power dissipation, and temperature junction. Many different IC package types are available. Examples include ball-grid array (BGA), chip-scale package (CSP), quad flat package (QFP), small outline package (SOP), and dual in-line package (DIP).

IC interfaces that are designed for the European marketplace must comply with the Restriction of Hazardous Substances (RoHS) directive from the European Union (EU). Some IC interfaces have an integrated charge pump or joint test action group (JTAG) pin. Others provide protection against electrostatic discharge (ESD), high temperatures, or over-voltage conditions.

Applications

IC interfaces differ in terms of device types and applications. Some products are used with buffers, CardBus controllers, codecs, crosspoint switches, framers, front-ends, isolators, internet protocol (IP) cores, or level translators. Others are used with liquid crystal display (LCD) drivers, light emitting diode (LED) drivers, line or bus controllers, line or bus drivers, link layer controllers, or media access controllers (MAC). IC interfaces for PCI bridges, PCIe bridges, port or bus expanders, and physical layer controllers (Phy controllers) are also available.

IC Interfaces FAQs

What do IC Bus Interfaces and Controllers do?

IC bus interfaces and controllers provide the common interface needed for connecting devices such as HDD, CD, and DVD drives or memory cards. They can support full duplex communication between multiple devices using only two lines (clock and data) and can operate at speeds from 10kbps to 400Mbps.

How are IC Bus Interfaces and Controllers used?

They are used in applications that demand storage and connectivity for digital content, such as personal video recorders (PVRs), set-top boxes (STBs), information appliances, home gateways, simple routers, and routers with network shared storage and/or printers.

What is the I2C bus specification?

The I2C bus specification, originally developed by Philips Inc., is used for data transfer between ICs at the PCB level. It consists of two open-collector lines for clock (SCL) and data (SDA) and supports both 7-bit and 10-bit addressing modes, allowing for multiple devices on the bus.

What are the different types of IC bus interfaces and controllers?

USB interfaces connect computers and peripherals and can also be used for PC-telephone and video conferencing connections. They operate as a bi-directional serial interface cable bus, transferring data at various rates over a maximum cable length of 4 meters using four wires, two of which carry data on a balanced twisted pair.

The I2C bus specification, originally developed by Philips Inc., is used for data transfer between ICs at the PCB level. It consists of two open-collector lines for clock (SCL) and data (SDA) and supports both 7-bit and 10-bit addressing modes, allowing for multiple devices on the bus.

These are used for connecting different components within a computer system, allowing for communication between the processor and peripheral devices.

These controllers are used in applications demanding storage and connectivity for digital content, such as personal video recorders (PVRs), set-top boxes (STBs), information appliances, home gateways, simple routers, and routers with network shared storage and/or printers.

What are the differences between USB and I2C interfaces?

Here are the differences between USB and I2C interfaces:

USB interfaces are primarily used to connect computers and peripherals. They are also used for PC-telephone and video conferencing connections.

The I2C bus is used for data transfer between integrated circuits (ICs) at the printed circuit board (PCB) level. It is commonly used in applications that require communication between multiple devices on the same board.

USB operates as a bi-directional serial interface cable bus. It uses four wires, two of which carry data on a balanced twisted pair, and can transfer data at various rates over a maximum cable length of 4 meters.

The I2C bus consists of two open-collector lines: one for the clock (SCL) and one for data (SDA). It supports configurations with one Master/many Slave devices or multiple Master devices.

USB can operate at speeds ranging from 10 kbps to 400 Mbps, supporting three different speed modes. I2C operates at lower speeds, typically between 100 kHz and 400 kHz.

I2C supports both 7-bit and 10-bit addressing modes, allowing for up to 128 or 1024 physical devices on the bus, respectively. However, certain addresses are reserved, so slightly fewer usable addresses are available.

These differences highlight the distinct roles and capabilities of USB and I2C interfaces in electronic systems.

What are the typical configurations for I2C bus systems?

The I2C bus can be configured with one Master device and multiple Slave devices. The Master device is responsible for generating the clock source for the linked Slave devices. This configuration is common for systems where a single controller communicates with several peripheral devices.

The I2C bus also supports a configuration with multiple Master devices. In this setup, more than one device can initiate communication on the bus, allowing for more complex interactions between devices. However, this requires additional arbitration logic to manage bus access.

IC Interfaces Media Gallery

References

Electronics360—Bluetooth Chip is Reportedly Smallest Available

GlobalSpec—IC Bus Interfaces and Controllers