PCA9554PW - 8-Bit I/O Expander with Interrupt | NXP
MPN: PCA9554PW ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
PCA9554PW Overview
An I2C or SMBus I/O expander is an interface IC that bridges a serial control bus and parallel digital lines. In the product hierarchy, it belongs to interface ICs, then bus interface controllers, then GPIO expanders, and finally semiconductors. It reduces the number of host-controller pins required for control-panel status LEDs, switch inputs, alarm signals, and other low-to-moderate-speed digital I/O. Unlike a microcontroller, the PCA9554PW is not intended to execute application software; a connected processor reads and writes its registers through I2C.
The verified product data identifies eight parallel I/O lines, interrupt support, weak pull-up capability, configuration registers, a 2.3 V to 5.5 V supply range, and operation at both 100 kHz and 400 kHz bus rates. Distributor listings identify the PW package as 16-pin TSSOP. These features suit systems where local logic voltage is below 5.5 V and the designer needs deterministic register-based port expansion. The interrupt output can notify the host when a configured input changes, reducing unnecessary polling while preserving straightforward firmware control.
The PCA9554 family uses configurable registers to define each port line as input or output and to control input polarity inversion. The verified NXP result specifically distinguishes PCA9554PW from PCA9554A, whose address differs. Firmware, pull-up implementation, and power sequencing therefore need review before substituting the A variant into an existing design. The verified data does not provide complete electrical limits, output-drive capability, timing values, or detailed pin mapping, so those items must be confirmed in the manufacturer datasheet before layout or sign-off.
Typical applications include remote control-panel indicators, configuration and mode switches, keypad or button inputs, alarm and interrupt signaling, small industrial modules, and low-speed embedded controllers. Placing eight digital lines behind one I2C address is especially useful when the host MCU has insufficient spare pins. The 400 kHz capability shortens transfer time compared with 100 kHz operation, although actual bus timing remains bounded by the slowest device, pull-up resistance, capacitance, and firmware behavior.
Design with the I2C pull-ups on SDA and SCL, keep the interrupt trace short, and confirm signal levels against the host supply. Do not assume that every similarly named PCA9554 device has the same address or register behavior. A socketed prototype should be tested for address conflicts, bus capacitance, input polarity, and active interrupt behavior. This page combines verified manufacturer and distributor facts with engineering guidance while clearly separating unavailable specifications.
The product information on this page also highlights why direct MPN review matters: package suffix, address variant, and bus details determine interchangeability. Before ordering or replacing PCA9554PW, verify the exact suffix, lifecycle status, pinout, and electrical limits against current manufacturer documentation.
Drop-in alternatives for PCA9554PW — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PCA9554PW (same form factor and footprint) — differing in Package, Product Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PCA9554APW
✅ Drop-In📋 Reference alternative (not in catalog)
PCA9554ADWR
✅ Drop-In📋 Reference alternative (not in catalog)
TCA9554PWR
✅ Drop-In📋 Reference alternative (not in catalog)
PCA9535PWR
✅ Drop-In📋 Reference alternative (not in catalog)
PCA9554PW/DG,118
✅ Drop-In📋 Reference alternative (not in catalog)
PCA9554PW Specifications
| Product Type | 8-bit I2C/SMBus I/O expander with interrupt |
| Number of GPIO | 8 bits |
| Supply Voltage Range | 2.3 V to 5.5 V |
| I2C/SMBus Maximum Frequency | 400 kHz |
| I2C/SMBus Supported Frequency | 100 kHz and 400 kHz |
| Interface | I2C-bus/SMBus |
| Interrupt Support | Yes |
| Port Register Features | Input/output and polarity configuration registers |
| Pull-Up Capability | Weak pull-up |
| Address Difference | PCA9554A has a different address |
| Package | 16-pin TSSOP |
| Mounting Type | Surface mount |
PCA9554PW 16-pin tssop Pin Configuration Guide
Pin configuration for PCA9554PW (16-pin tssop package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for PCA9554PW.
Refer to the datasheet for full pin configuration.
Typical Applications
PCA9554PW is suitable for 7 applications: Control Panel Indicators, Switch and Button Inputs, Alarm and Status Signaling, Remote Sensor Interface, Embedded Configuration Interface, Industrial Module Backplane, Low-Speed Peripheral Control.
Control Panel Indicators
PCA9554PW is appropriate for control-panel status and indicator lines because it provides eight programmable digital outputs on an I2C/SMBus interface. A host controller can update multiple LED or relay-control signals through one serial address instead of dedicating eight GPIO pins. The interrupt output can also notify the controller when a configured input changes. Because the verified data does not state per-pin current limits, LED drive strength, polarity, and any required transistor drivers must be checked against the datasheet before layout.
Recommended
Switch and Button Inputs
Use PCA9554PW when a compact module has more switch or button inputs than the host MCU can expose directly. The eight lines can be configured as inputs, read through the device registers, and monitored with the interrupt output when a change occurs. The verified product data confirms interrupt support and configuration registers, while the 400 kHz bus capability helps keep register polling responsive. Debounce policy, polarity, pull-up arrangement, and electrical thresholds must be defined in firmware and validated against the complete NXP datasheet.
Recommended
Alarm and Status Signaling
PCA9554PW can centralize alarm, fault, and equipment-status signals in industrial or embedded systems. The host writes output states for indicators and reads input states from sensors or external fault lines through the same I2C interface. Interrupt support can reduce routine polling when a monitored input changes. The device's 2.3 V to 5.5 V verified supply range supports mixed low-voltage systems, but isolation, voltage levels, surge protection, and fail-safe states require separate application design.
Recommended
Remote Sensor Interface
The PCA9554PW is useful for small remote sensor modules whose digital outputs exceed the host's available GPIO budget. It does not perform analog measurement; instead, it collects discrete sensor-alarm, threshold, or presence signals and exposes them through registers. The 100 kHz and 400 kHz verified bus rates support both simple control loops and more responsive status polling. Sensor supply voltage, signal polarity, isolation, and cable-length effects must be checked separately from the expander's own specifications.
Recommended
Embedded Configuration Interface
PCA9554PW fits configuration boards that need mode straps, feature enables, or front-panel state inputs. The host can read the port state at boot and change output states during testing without using a larger host MCU package. Configuration registers and configurable polarity help simplify application firmware, while the TSSOP package supports compact board layouts. Confirm the verified pinout, package dimensions, and logic thresholds before finalizing a PCB because those details are not included in the supplied source data.
Recommended
Industrial Module Backplane
PCA9554PW can add distributed digital control to an industrial module or backplane where a controller communicates over I2C rather than through a large parallel connector. Eight lines can handle latch, enable, reset, or interlock signals, while the interrupt line provides event notification. The verified 400 kHz capability is useful for shared buses, but address planning, pull-up placement, cable capacitance, and grounding determine whether the final network remains reliable.
Recommended
Low-Speed Peripheral Control
PCA9554PW can provide a compact register-based interface between a host controller and low-speed peripherals such as indicators, latches, and discrete control inputs. Its 8-bit organization maps naturally to byte-oriented firmware, allowing a driver to read, write, and configure the port through I2C. At 400 kHz, the device can reduce transaction time compared with 100 kHz operation, although system throughput still depends on bus loading and host software. Use the NXP datasheet for timing and output-drive details.
Recommended
Recommended Products Summary
Engineering reference data for PCA9554PW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PCA9554APW | PCA9554ADWR | TCA9554PWR | PCA9535PWR | PCA9554PW/DG,118 |
|---|---|---|---|---|---|---|
| Package | 16-pin TSSOP | 16-pin TSSOP | 16-pin TSSOP | 16-pin TSSOP | 16-pin TSSOP | 16-pin TSSOP |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | Texas Instruments | Texas Instruments | NXP Semiconductors |
| Interface | I2C/SMBus | I2C/SMBus | I2C/SMBus | I2C/SMBus | I2C/SMBus | I2C/SMBus |
Key Differentiators
- Directly identified NXP 8-bit I2C/SMBus expander with interrupt (vs TCA9554PWR)
- Same PCA9554 family identity for existing PCA9554-based designs (vs PCA9554APW)
- Verified 400 kHz distributor specification and interrupt feature (vs PCA9535PWR)
Design Notes
Design the I2C pull-up network for the actual bus voltage and capacitance rather than assuming a default value. The verified PCA9554PW data specifies a 2.3 V to 5.5 V supply range, but it does not provide the required pull-up resistance or logic thresholds. Check SDA and SCL pull-up voltage, resistance, rise time, and the current budget against the final bus capacitance and the NXP datasheet.
Keep the PCA9554PW close to the host controller and place its required bypass and bus pull-up connections according to the manufacturer layout guidance. Route SDA and SCL away from noisy switching nodes, keep the interrupt trace short, and provide a clean ground reference. The verified data confirms interrupt support but does not specify the package pinout, so pin placement must be checked before PCB release.
Do not substitute PCA9554A, TCA9554PWR, or PCA9535PWR based only on the shared 8-bit I/O description. The verified data specifically says PCA9554A has a different address, while the other comparison candidates lack complete pin, register, and timing verification. Review address, polarity, interrupt behavior, power range, and package pin assignments before approving a replacement.
Compliance Information
The supplied verified data does not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. Confirm current compliance documents with NXP or the authorized distributor.
