PCA9555PW - 16-Bit I2C GPIO Expander | NXP Semiconductors
料号： PCA9555PW ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
PCA9555PW 概述
A GPIO expander is an interface IC that increases the number of digital input and output pins available to a host processor. The PCA9555 belongs to the I2C I/O-expander class, within interface ICs and the broader embedded-control semiconductor hierarchy. Each port bit can be configured independently for input or output, allowing control of LEDs, relays, logic levels, key inputs, and other digital peripherals through the serial bus instead of dedicating host-controller pins.
The supplied product information identifies the device as a 16-bit I2C-bus/SMBus GPIO expander with interrupt support. Nexperia’s product information for the same PCA9555PW family specifies a wide 2.3 V to 5.5 V operating range and default GPIO pull-up resistors. The verified distributor results identify NXP’s PCA9555PW as an I/O expander in a 24-TSSOP package, while the UMW listing presents the same MPN as a 1 MHz I2C/SMBus variant; that listing is retained as market evidence but is not used to overwrite the target manufacturer specification.
The device is useful when a controller has insufficient GPIO resources, especially in industrial controllers, embedded systems, sensors, and compact automation products. The serial interface reduces wiring complexity, while the interrupt output allows a host to respond to input changes without continuously polling the bus. GPIO electrical limits, address options, and detailed timing values were not supplied in the verified data and must be confirmed in the manufacturer datasheet before final design release.
For robust PCB implementation, preserve the package footprint and pin numbering, confirm the intended I2C address, route the interrupt line away from fast switching nodes, and validate pull-up resistor values against the bus voltage and capacitance. Do not treat a distributor listing as a substitute for the NXP datasheet when selecting address strapping, power sequencing, or input thresholds.
直接替换替代料： PCA9555PW ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： PCA9555PW （相同外形与封装尺寸） ——差异在于 Package, Function, Interface, Interrupt Output, MSL Level.
快速对比工具——选择替代料号进行并排对比：
PCA9555PW,118
✅ 直接替换📋 参考替代料（不在目录中）
TCA9555PWR
✅ 直接替换✓ 有现货
$0.79 / 个
查看数据手册 →CAT9555YI-T2
✅ 直接替换📋 参考替代料（不在目录中）
PCA9555PW 规格参数
| Device Type | 16-bit I2C-bus/SMBus GPIO expander |
| Number of GPIO Ports | 16 ports |
| 封装 | 24-pin TSSOP |
| Supply Voltage Range | 2.3 V to 5.5 V |
| I2C/SMBus Frequency | 400 kHz |
| Interrupt Support | Yes |
| Default GPIO Pull-Up Resistors | Yes |
| I/O Direction | Configurable input or output per port bit |
| Device Interface | I2C-bus/SMBus |
| Logic Family | CMOS |
| 安装类型 | Surface mount |
| 引脚数量 | 24 pins |
PCA9555PW 24-pin tssop 引脚配置指南
PCA9555PW（24-pin tssop 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： PCA9555PW.
请参阅 数据手册 以查看完整引脚配置。
典型应用
PCA9555PW 适用于 6 应用s: Industrial Control Panel, Embedded Sensor Hub, LED and Relay Control, Human-Machine Interface, Battery-Powered IoT Controller, Test and Measurement Front Panel.
Industrial Control Panel
The PCA9555PW is suitable for expanding a compact industrial controller when the host MCU needs additional digital status and control points. Its 16 GPIO lines can represent relay-control outputs, switch inputs, alarm signals, or actuator-enable signals while retaining I2C-bus/SMBus connectivity. The 2.3 V to 5.5 V range accommodates common embedded control rails, and interrupt support can notify the controller when an input changes. The TSSOP package helps keep the footprint compact, but address strapping, pull-up values, and output drive limits must be verified from the NXP datasheet before production.
推荐
Embedded Sensor Hub
PCA9555PW can add discrete digital sensor-enable, alert, ready, and configuration lines to an embedded sensor hub without consuming every GPIO on the host processor. Sixteen independently usable input/output ports make it practical for aggregating status from multiple sensor modules while keeping the serial interconnect compact. Interrupt support can reduce unnecessary polling when a sensor reports a change through a digital status line. The verified 2.3 V to 5.5 V operating range supports common sensor-hub rails, while detailed logic thresholds and timing should be checked against the complete system voltage and bus capacitance.
推荐
LED and Relay Control
The PCA9555PW can control LED indicators, relay drivers, and discrete digital loads through its 16 GPIO outputs, allowing a low-pin-count controller to supervise multiple channels. Its interrupt function is also useful when some channels are configured as inputs for status feedback or push-button events. The verified 400 kHz I2C listing provides a defined serial-bus context, but the designer must check per-pin current limits, external transistor or driver requirements, inductive-load suppression, and startup states. A 24-pin TSSOP package supports compact control boards but still requires careful decoupling and current planning.
推荐
Human-Machine Interface
PCA9555PW fits a compact human-machine interface where limit switches, keypads, LEDs, and indicator lamps exceed the available host GPIO. Input lines can report switch states, while output lines can drive indicator segments or control-enable signals. The device’s interrupt capability allows the controller to react to an input transition with less continuous bus activity, which can simplify firmware organization. The verified 2.3 V to 5.5 V range is useful across mixed embedded rails, but the final design should confirm input thresholds, debouncing strategy, pull-up behavior, and package pin mapping in the manufacturer documentation.
推荐
Battery-Powered IoT Controller
PCA9555PW can reduce the number of direct host-controller pins required in a small IoT node that monitors discrete inputs and drives low-current indicators or enables. The serial interface helps preserve PCB area, while the 2.3 V to 5.5 V supply range can support common embedded supply architectures. Battery applications still require a careful review of sleep behavior, leakage current, pull-up current, and whether the interrupt line can remain active during low-power operation. Those values are not supplied in the verified snippets and must be obtained from the current NXP datasheet before battery-life calculations are finalized.
推荐
Test and Measurement Front Panel
PCA9555PW is useful in a test or measurement instrument that needs multiple digital control and status lines for front-panel buttons, relay selection, trigger enables, or fault indicators. A host processor can manage the lines through I2C-bus/SMBus and use the interrupt output to report asynchronous panel events. The 16-GPIO count reduces parallel wiring and can simplify connector routing, while the 24-pin TSSOP package provides a compact surface-mount solution. Verify signal integrity, pull-up placement, input protection, and any long external cable behavior before using the device with front-panel wiring.
推荐
推荐产品汇总
工程参考数据： PCA9555PW ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | PCA9555PW,118 | TCA9555PWR | CAT9555YI-T2 |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | Texas Instruments | onsemi |
关键差异点
- 16 GPIO expansion in a 24-pin TSSOP package （对比 TCA9555PWR)
- 2.3 V to 5.5 V operating range （对比 CAT9555YI-T2)
- Interrupt-capable I2C/SMBus expansion （对比 PCA9555PW,118)
设计说明
Keep the I2C-bus traces short, place pull-up resistors near the bus nodes, and route the PCA9555PW ground and supply connections close to the device pins. Confirm address-strapping connections against the actual datasheet before laying out the board. The verified data confirms a 24-pin TSSOP package but does not provide a pin-level drawing, so do not infer connections from the package name alone.
Validate pull-up resistance, bus capacitance, rise-time, and the 400 kHz distributor-listed I2C rate together rather than selecting the resistor in isolation. The I2C lines are open-drain-style signals in the intended bus, and excessive resistance can slow edges, while excessively low resistance can increase sink current. Use oscilloscope measurements on the assembled bus when timing margin is important.
Do not assume that a same-package part is a drop-in replacement. The verified search identifies TCA9555PWR and CAT9555YI-T2 as candidates, but pinout, address behavior, interrupt polarity, voltage limits, GPIO drive strength, timing, and default states must be checked in each manufacturer datasheet. Also verify the actual PCA9555PW pin map before assigning external signals or applying power.
合规信息
The supplied verified search data does not state compliance status for PCA9555PW. Confirm RoHS, REACH, lead-free, halogen-free, conflict-minerals, and automotive qualification documents with NXP or the authorized distributor before release.
