PCA9555 CMOS Device: Datasheet, Pinout, Application Circuit
24 Termination 0.65mm 2.5/5V I/O Expander PCA9555 3V 24-TSSOP (0.173, 4.40mm Width)









24 Termination 0.65mm 2.5/5V I/O Expander PCA9555 3V 24-TSSOP (0.173, 4.40mm Width)
The PCA9555 is a 24-pin CMOS device, and this post mainly covers its pinout, datasheet, application and more details, furthermore, there is a huge range of Semiconductors, Capacitors, Resistors and ICs in stock. Welcome RFQ.

PCA9555 32-Bit GPIO Expander with Arduino
PCA9555 Pinout

PCA9555 Pinout
PCA9555 CAD Model
Symbol

PCA9555 Symbol
Footprint

PCA9555 Footprint
3D Model

PCA9555 3D Model
What is PCA9555?
The PCA9555 is a 24-pin CMOS device that provides 16 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders.
The PCA9555 consists of two 8-bit Configuration (Input or Output selection); Input, Output and Polarity Inversion (active HIGH or active LOW operation) registers. The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits.
The PCA9555 open-drain interrupt output is activated when any input state differs from its corresponding input port register state and is used to indicate to the system master that an input state has changed. The power-on reset sets the registers to their default values and initializes the device state machine.
Specifications
- TypeParameter
- Factory Lead Time7 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 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.
Tape & Reel (TR) - Published2003
- 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 - 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
- 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) - HTS Code
HTS (Harmonized Tariff Schedule) codes are product classification codes between 8-1 digits. The first six digits are an HS code, and the countries of import assign the subsequent digits to provide additional classification. U.S. HTS codes are 1 digits and are administered by the U.S. International Trade Commission.
8542.39.00.01 - 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 - Time@Peak Reflow Temperature-Max (s)
Time@Peak Reflow Temperature-Max (s) refers to the maximum duration that an electronic component can be exposed to the peak reflow temperature during the soldering process, which is crucial for ensuring reliable solder joint formation without damaging the component.
30 - 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.
PCA9555 - Pin Count
a count of all of the component leads (or pins)
24 - JESD-30 Code
JESD-30 Code refers to a standardized descriptive designation system established by JEDEC for semiconductor-device packages. This system provides a systematic method for generating designators that convey essential information about the package's physical characteristics, such as size and shape, which aids in component identification and selection. By using JESD-30 codes, manufacturers and engineers can ensure consistency and clarity in the specification of semiconductor packages across various applications and industries.
R-PDSO-G24 - Qualification Status
An indicator of formal certification of qualifications.
Not Qualified - 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 - Power Supplies
an electronic circuit that converts the voltage of an alternating current (AC) into a direct current (DC) voltage.?
2.5/5V - 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 - Length7.8mm
- Height Seated (Max)
Height Seated (Max) is a parameter in electronic components that refers to the maximum allowable height of the component when it is properly seated or installed on a circuit board or within an enclosure. This specification is crucial for ensuring proper fit and alignment within the overall system design. Exceeding the maximum seated height can lead to mechanical interference, electrical shorts, or other issues that may impact the performance and reliability of the electronic device. Manufacturers provide this information to help designers and engineers select components that will fit within the designated space and function correctly in the intended application.
1.1mm - Width4.4mm
- RoHS Status
RoHS means “Restriction of Certain Hazardous Substances” in the “Hazardous Substances Directive” in electrical and electronic equipment.
ROHS3 Compliant
Parts with Similar Specs
- ImagePart NumberManufacturerPackage / CaseInterfaceSupply VoltageRoHS StatusLengthMoisture Sensitivity Level (MSL)Qualification StatusTerminal PositionView Compare
PCA9555PW,118
24-TSSOP (0.173, 4.40mm Width)
I2C, SMBus
3 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
Not Qualified
DUAL
24-TSSOP (0.173, 4.40mm Width)
I2C, SMBus
3 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
Not Qualified
DUAL
24-TSSOP (0.173, 4.40mm Width)
I2C, SMBus
2.5 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
Not Qualified
DUAL
24-TSSOP (0.173, 4.40mm Width)
I2C, SMBus
3 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
Not Qualified
DUAL
24-TSSOP (0.173, 4.40mm Width)
I2C, SMBus
2.5 V
ROHS3 Compliant
7.8 mm
1 (Unlimited)
Not Qualified
DUAL
PCA9555 Feature
■ Operating power supply voltage range of 2.3 V to 5.5 V
■ 5 V tolerant I/Os
■ Polarity Inversion register
■ The active LOW interrupt output
■ Low standby current
■ Noise filter on SCL/SDA inputs
■ No glitch on power-up
■ Internal power-on reset
■ 16 I/O pins which default to 16 inputs
■ 0 Hz to 400 kHz clock frequency
■ ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per JESD22-A115, and 1000 V CDM per JESD22-C101
■ Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
■ Six packages offered: DIP24, SO24, SSOP24, TSSOP24, HVQFN24 and HWQFN2
PCA9555 Typical Application Circuit
PCA9555 Block Diagram

PCA9555 Block Diagram
PCA9555 Package

PCA9555 Package
Note: Other packages of PCA9555 can be taken from the datasheet below.
PCA9555 Manufacturer
NXP Semiconductors is dedicated to providing secure connectivity solutions for embedded applications, the company has 45,000 employees in more than 35 countries. and has been operating, with its experience and expertise, for more than 60 years. As a leader in this field, NXP is driving innovation in the secure connected vehicle, end-to-end security & privacy and smart connected solutions markets, with the hope of making lives easier, better and safer Freescale Semiconductor parts are now a part of the NXP family.
Datasheet PDF
- Datasheets :
- PCN Packaging :
- Environmental Information :
Popularity by Region
How many package does PCA9555 offer?
It offered 6 packages: DIP24, SO24, SSOP24, TSSOP24, HVQFN24 and HWQFN2.
What is the operating power supply voltage of PCA9555?
Operating power supply voltage range of 2.3 V to 5.5 V.
What about the clock frequency of PCA9555?
It is a 0 Hz to 400 kHz clock frequency.
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