PCA9555PW Expander: Features, Applications and Datasheet
24 Termination 0.65mm I/O Expander CA9555 24 Pin 3V 24-TSSOP (0.173, 4.40mm Width)









24 Termination 0.65mm I/O Expander CA9555 24 Pin 3V 24-TSSOP (0.173, 4.40mm Width)
The Texas Instruments PCA9555PW is a remote 16-bit I2C and SMBus I/O expander with interrupt output and configuration registers. This articles will introduce its features, applications and datasheet.
PCA9555PW Description
The Texas Instruments PCA9555PW is a remote 16-bit I2C and SMBus I/O expander with interrupt output and configuration registers. It can be used to increase the number of input/output pins available for microcontrollers or microprocessors through a serial interface. It operates with a supply voltage range of 2.3 V to 5.5 V and supports a maximum clock frequency of 400 kHz. It also has built-in ESD protection and weak pull-up resistors.
PCA9555PW Features
It is a remote 16-bit I2C and SMBus I/O expander that can increase the number of input/output pins available for microcontrollers or microprocessors through a serial interface.
It has interrupt output and configuration registers that allow the user to control the polarity, direction, and input/output state of each pin.
It operates with a supply voltage range of 2.3 V to 5.5 V and supports a maximum clock frequency of 400 kHz.
It has 5 V tolerant I/Os, built-in ESD protection, and weak pull-up resistors.
It has a low stand-by current, a noise filter on SCL/SDA inputs, and no glitch on power-up
Specifications
- TypeParameter
- Lifecycle Status
Lifecycle Status refers to the current stage of an electronic component in its product life cycle, indicating whether it is active, obsolete, or transitioning between these states. An active status means the component is in production and available for purchase. An obsolete status indicates that the component is no longer being manufactured or supported, and manufacturers typically provide a limited time frame for support. Understanding the lifecycle status is crucial for design engineers to ensure continuity and reliability in their projects.
ACTIVE (Last Updated: 3 days ago) - Factory Lead Time6 Weeks
- Mounting Type
The "Mounting Type" in electronic components refers to the method used to attach or connect a component to a circuit board or other substrate, such as through-hole, surface-mount, or panel mount.
Surface Mount - Package / Case
refers to the protective housing that encases an electronic component, providing mechanical support, electrical connections, and thermal management.
24-TSSOP (0.173, 4.40mm Width) - Surface Mount
having leads that are designed to be soldered on the side of a circuit board that the body of the component is mounted on.
YES - Number of Pins24
- Weight89.499445mg
- Number of I/Os16
- Operating Temperature
The operating temperature is the range of ambient temperature within which a power supply, or any other electrical equipment, operate in. This ranges from a minimum operating temperature, to a peak or maximum operating temperature, outside which, the power supply may fail.
-40°C~85°C - Packaging
Semiconductor package is a carrier / shell used to contain and cover one or more semiconductor components or integrated circuits. The material of the shell can be metal, plastic, glass or ceramic.
Tube - JESD-609 Code
The "JESD-609 Code" in electronic components refers to a standardized marking code that indicates the lead-free solder composition and finish of electronic components for compliance with environmental regulations.
e4 - Pbfree Code
The "Pbfree Code" parameter in electronic components refers to the code or marking used to indicate that the component is lead-free. Lead (Pb) is a toxic substance that has been widely used in electronic components for many years, but due to environmental concerns, there has been a shift towards lead-free alternatives. The Pbfree Code helps manufacturers and users easily identify components that do not contain lead, ensuring compliance with regulations and promoting environmentally friendly practices. It is important to pay attention to the Pbfree Code when selecting electronic components to ensure they meet the necessary requirements for lead-free applications.
yes - Part Status
Parts can have many statuses as they progress through the configuration, analysis, review, and approval stages.
Active - Moisture Sensitivity Level (MSL)
Moisture Sensitivity Level (MSL) is a standardized rating that indicates the susceptibility of electronic components, particularly semiconductors, to moisture-induced damage during storage and the soldering process, defining the allowable exposure time to ambient conditions before they require special handling or baking to prevent failures
1 (Unlimited) - Number of Terminations24
- ECCN Code
An ECCN (Export Control Classification Number) is an alphanumeric code used by the U.S. Bureau of Industry and Security to identify and categorize electronic components and other dual-use items that may require an export license based on their technical characteristics and potential for military use.
EAR99 - Terminal Finish
Terminal Finish refers to the surface treatment applied to the terminals or leads of electronic components to enhance their performance and longevity. It can improve solderability, corrosion resistance, and overall reliability of the connection in electronic assemblies. Common finishes include nickel, gold, and tin, each possessing distinct properties suitable for various applications. The choice of terminal finish can significantly impact the durability and effectiveness of electronic devices.
Nickel/Palladium/Gold (Ni/Pd/Au) - Voltage - Supply
Voltage - Supply refers to the range of voltage levels that an electronic component or circuit is designed to operate with. It indicates the minimum and maximum supply voltage that can be applied for the device to function properly. Providing supply voltages outside this range can lead to malfunction, damage, or reduced performance. This parameter is critical for ensuring compatibility between different components in a circuit.
2.3V~5.5V - Terminal Position
In electronic components, the term "Terminal Position" refers to the physical location of the connection points on the component where external electrical connections can be made. These connection points, known as terminals, are typically used to attach wires, leads, or other components to the main body of the electronic component. The terminal position is important for ensuring proper connectivity and functionality of the component within a circuit. It is often specified in technical datasheets or component specifications to help designers and engineers understand how to properly integrate the component into their circuit designs.
DUAL - Terminal Form
Occurring at or forming the end of a series, succession, or the like; closing; concluding.
GULL WING - Peak Reflow Temperature (Cel)
Peak Reflow Temperature (Cel) is a parameter that specifies the maximum temperature at which an electronic component can be exposed during the reflow soldering process. Reflow soldering is a common method used to attach electronic components to a circuit board. The Peak Reflow Temperature is crucial because it ensures that the component is not damaged or degraded during the soldering process. Exceeding the specified Peak Reflow Temperature can lead to issues such as component failure, reduced performance, or even permanent damage to the component. It is important for manufacturers and assemblers to adhere to the recommended Peak Reflow Temperature to ensure the reliability and functionality of the electronic components.
260 - Supply Voltage
Supply voltage refers to the electrical potential difference provided to an electronic component or circuit. It is crucial for the proper operation of devices, as it powers their functions and determines performance characteristics. The supply voltage must be within specified limits to ensure reliability and prevent damage to components. Different electronic devices have specific supply voltage requirements, which can vary widely depending on their design and intended application.
3V - Terminal Pitch
The center distance from one pole to the next.
0.65mm - Base Part Number
The "Base Part Number" (BPN) in electronic components serves a similar purpose to the "Base Product Number." It refers to the primary identifier for a component that captures the essential characteristics shared by a group of similar components. The BPN provides a fundamental way to reference a family or series of components without specifying all the variations and specific details.
CA9555 - Pin Count
a count of all of the component leads (or pins)
24 - Number of Outputs2
- Output Type
The "Output Type" parameter in electronic components refers to the type of signal or data that is produced by the component as an output. This parameter specifies the nature of the output signal, such as analog or digital, and can also include details about the voltage levels, current levels, frequency, and other characteristics of the output signal. Understanding the output type of a component is crucial for ensuring compatibility with other components in a circuit or system, as well as for determining how the output signal can be utilized or processed further. In summary, the output type parameter provides essential information about the nature of the signal that is generated by the electronic component as its output.
Push-Pull - Interface
In electronic components, the term "Interface" refers to the point at which two different systems, devices, or components connect and interact with each other. It can involve physical connections such as ports, connectors, or cables, as well as communication protocols and standards that facilitate the exchange of data or signals between the connected entities. The interface serves as a bridge that enables seamless communication and interoperability between different parts of a system or between different systems altogether. Designing a reliable and efficient interface is crucial in ensuring proper functionality and performance of electronic components and systems.
I2C, SMBus - Number of Ports
A port is identified for each transport protocol and address combination by a 16-bit unsigned number,.
2 - Number of Bits16
- Clock Frequency
Clock frequency, also known as clock speed, refers to the rate at which a processor or electronic component can execute instructions. It is measured in hertz (Hz) and represents the number of cycles per second that the component can perform. A higher clock frequency typically indicates a faster processing speed and better performance. However, it is important to note that other factors such as architecture, efficiency, and workload also play a significant role in determining the overall performance of a component. In summary, clock frequency is a crucial parameter that influences the speed and efficiency of electronic components in processing data and executing tasks.
400kHz - Interrupt Output
In electronic components, "Interrupt Output" refers to a feature that allows a device to signal the occurrence of a specific event or condition that requires immediate attention from the system or user. When the specified event occurs, the interrupt output generates a signal to pause the normal operation of the device and divert the attention to handle the urgent task. This feature is commonly used in microcontrollers, processors, and other integrated circuits to efficiently manage tasks and prioritize critical operations. By utilizing interrupt outputs, electronic systems can respond promptly to important events, improve overall performance, and enhance real-time responsiveness.
Yes - Current - Output Source/Sink
The parameter "Current - Output Source/Sink" in electronic components refers to the maximum amount of current that the component can either source (provide) or sink (absorb) at its output pin. This parameter is crucial in determining the capability of the component to drive external loads such as other components or devices. The source current indicates the maximum current that the component can supply to the load, while the sink current indicates the maximum current that the component can draw from the load. Understanding this parameter is essential for designing circuits that require specific current-handling capabilities to ensure proper functionality and reliability.
10mA 25mA - Features
In the context of electronic components, the term "Features" typically refers to the specific characteristics or functionalities that a particular component offers. These features can vary depending on the type of component and its intended use. For example, a microcontroller may have features such as built-in memory, analog-to-digital converters, and communication interfaces like UART or SPI.When evaluating electronic components, understanding their features is crucial in determining whether they meet the requirements of a particular project or application. Engineers and designers often look at features such as operating voltage, speed, power consumption, and communication protocols to ensure compatibility and optimal performance.In summary, the "Features" parameter in electronic components describes the unique attributes and capabilities that differentiate one component from another, helping users make informed decisions when selecting components for their electronic designs.
POR - Height1.2mm
- Length7.8mm
- Width4.4mm
- Thickness
Thickness in electronic components refers to the measurement of how thick a particular material or layer is within the component structure. It can pertain to various aspects, such as the thickness of a substrate, a dielectric layer, or conductive traces. This parameter is crucial as it impacts the electrical, mechanical, and thermal properties of the component, influencing its performance and reliability in electronic circuits.
1mm - REACH SVHC
The parameter "REACH SVHC" in electronic components refers to the compliance with the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) regulation regarding Substances of Very High Concern (SVHC). SVHCs are substances that may have serious effects on human health or the environment, and their use is regulated under REACH to ensure their safe handling and minimize their impact.Manufacturers of electronic components need to declare if their products contain any SVHCs above a certain threshold concentration and provide information on the safe use of these substances. This information allows customers to make informed decisions about the potential risks associated with using the components and take appropriate measures to mitigate any hazards.Ensuring compliance with REACH SVHC requirements is essential for electronics manufacturers to meet regulatory standards, protect human health and the environment, and maintain transparency in their supply chain. It also demonstrates a commitment to sustainability and responsible manufacturing practices in the electronics industry.
No SVHC - Radiation Hardening
Radiation hardening is the process of making electronic components and circuits resistant to damage or malfunction caused by high levels of ionizing radiation, especially for environments in outer space (especially beyond the low Earth orbit), around nuclear reactors and particle accelerators, or during nuclear accidents or nuclear warfare.
No - RoHS Status
RoHS means “Restriction of Certain Hazardous Substances” in the “Hazardous Substances Directive” in electrical and electronic equipment.
ROHS3 Compliant - Lead Free
Lead Free is a term used to describe electronic components that do not contain lead as part of their composition. Lead is a toxic material that can have harmful effects on human health and the environment, so the electronics industry has been moving towards lead-free components to reduce these risks. Lead-free components are typically made using alternative materials such as silver, copper, and tin. Manufacturers must comply with regulations such as the Restriction of Hazardous Substances (RoHS) directive to ensure that their products are lead-free and environmentally friendly.
Lead Free
PCA9555PW Pinout


PCA9555PW CAD Model
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Footprint

3D Model

PCA9555PW Applications
It can be used to control LED displays and keypads through a serial interface, reducing the number of pins required for microcontrollers or microprocessors.
It can be used to monitor switches, sensors, and push buttons and generate an interrupt signal when a change is detected.
It can be used to expand the I/O capabilities of devices that have limited or no I/O ports, such as serial EEPROMs, real-time clocks, and temperature sensors.
It can be used to implement parallel interfaces for devices that only have serial interfaces, such as LCD modules, ADCs, and DACs.
It can be used to isolate I/O signals from noisy environments or high-voltage circuits, providing protection and level shifting
PCA9555PW Manufacturer
Texas Instruments is an American technology company that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globally. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company’s focus is on developing analog chips and embedded processors, which account for more than 80% of its revenue. TI also produces TI digital light processing technology and education technology products including calculators, microcontrollers, and multi-core processors. The company holds 45,000 patents worldwide as of 2016.
Parts with Similar Specs
- ImagePart NumberManufacturerPackage / CaseNumber of PinsNumber of OutputsSupply VoltageRoHS StatusLengthMoisture Sensitivity Level (MSL)Number of TerminationsView Compare
PCA9555PW
24-TSSOP (0.173, 4.40mm Width)
24
2
3 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
24
24-TSSOP (0.173, 4.40mm Width)
24
1
2.5 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
24
24-TSSOP (0.173, 4.40mm Width)
-
1
2.5 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
24
24-TSSOP (0.173, 4.40mm Width)
-
-
3 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
24
24-TSSOP (0.173, 4.40mm Width)
-
-
2.5 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
24
Datasheet PDF
- PCN Design/Specification :
What is the PCA9555PW and what does it do?
The PCA9555PW is a remote 16-bit I2C and SMBus I/O expander with interrupt output and configuration registers. It can be used to increase the number of input/output pins available for microcontrollers or microprocessors through a serial interface.
How can I order the PCA9555PW?
You can order the PCA9555PW from various online distributors, such as Utmel, Mouser or Mouser Australia. You can also check the availability, price, and packaging options from these websites.
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