NXP Semiconductors PCA9554CBSHP

Overview

PCA9554CBSHP from NXP Semiconductors is an 8-bit I²C-bus/SMBus GPIO expander with interrupt output, weak internal pull-up resistors (100 kΩ), and 1.65 V to 5.5 V supply operation. It provides configurable input/output ports (P0–P7), polarity inversion, and hardware address selection via A0–A2 pins. Used in ACPI power switches, LED drivers, push-button interfaces, and sensor subsystems where minimal interconnect and low-power remote I/O are required.

For engineers reviewing the PCA9554CBSHP datasheet, PCA9554CBSHP pinout, PCA9554CBSHP application, or PCA9554CBSHP equivalent, this page delivers verified electrical parameters, HVQFN16 package details, interrupt behavior, register-level I/O control logic, and validated alternative parts for system-level I²C bus expansion design.

Technical Context

The PCA9554CBSHP implements a slave-only I²C interface compliant with Fast-mode (400 kHz) timing, featuring a fixed base address of 0x38 (0111xxx) for the PCA9554C variant. Its internal register map includes Input Port (00h), Output Port (01h), Polarity Inversion (02h), and Configuration (03h) registers - all accessible via standard I²C write/read sequences with pointer auto-increment.

Each of the eight I/O pins supports independent direction control, Schmitt-trigger inputs for noise immunity (V_HYS = 0.10 × V_DD), and 5 V-tolerant operation. The open-drain INT output activates on any input state change relative to the Input Port register and resets only upon reading the corresponding port register or restoring matching pin state.

Key Specifications

Pinout & Package

HVQFN16 package (3 mm × 3 mm × 0.85 mm body, exposed thermal pad); RoHS-compliant, lead-free, moisture sensitivity level 3 (MSL3).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C GPIO expander applications.

Compared with PCA9554BPW, PCA9554CBSHP offers superior thermal performance and smaller footprint in HVQFN16, while PCAL9554C adds configurability at the cost of firmware complexity and higher unit price - making PCA9554CBSHP the balanced choice for high-volume, space-constrained industrial I/O expansion.

Availability

PCA9554CBSHP is available at Aetrix Electronics and suitable for ACPI power management, LED status indication, push-button interface, and sensor subsystem expansion requiring stable component supply across automotive, industrial, and consumer electronics programs.

Supply support for PCA9554CBSHP includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in interface, power, and sensing technologies.

The PCA9554C series belongs to NXP's I²C GPIO expander product line, designed specifically to extend microcontroller I/O capability in space- and power-constrained embedded systems while maintaining bus efficiency and system-level reliability.

FAQ

What is the I²C slave address range for PCA9554CBSHP?

The PCA9554CBSHP is a PCA9554C variant with base I²C address 0x38 (0111xxx). Pins A2–A0 select the final 3 bits, yielding addresses 0x38 through 0x3F. This differs from the PCA9554B family (0x20–0x27), allowing up to 16 total devices on one bus without conflict. The PCA9554CBSHP address is fixed per hardware configuration and cannot be changed in software.

Does PCA9554CBSHP require external pull-up resistors on SDA/SCL lines?

Yes, PCA9554CBSHP requires external pull-up resistors on both SDA and SCL lines to ensure proper I²C bus operation - the internal 100 kΩ pull-ups apply only to the P0–P7 I/O pins when configured as inputs. Typical values are 2.2 kΩ to 10 kΩ depending on bus capacitance and speed; NXP recommends 4.7 kΩ for 400 kHz Fast-mode operation with ≤400 pF total bus capacitance.

How does the INT pin on PCA9554CBSHP get cleared after assertion?

The INT pin on PCA9554CBSHP is cleared automatically when the host reads the Input Port register (00h) corresponding to the port that triggered the interrupt - the ACK/NACK bit after the rising edge of SCL completes the reset. Alternatively, INT clears if the input pin state returns to match its prior value in the Input Port register. No explicit command or register write is needed to deassert INT.

Can PCA9554CBSHP drive LEDs directly, and what are the current limits?

Yes, PCA9554CBSHP can drive LEDs directly in sink configuration (anode to VDD, cathode to P0–P7). Each port pin supports up to 25 mA continuous sink current at VOL ≤ 0.7 V, verified across 1.65 V to 4.5 V VDD. For reliable long-term operation, NXP recommends limiting sustained current to 20 mA per pin and total device current (IDD) to <100 mA to maintain thermal stability in HVQFN16 package.

Is PCA9554CBSHP compatible with 5 V microcontrollers when powered at 3.3 V?

Yes, PCA9554CBSHP is 5 V-tolerant on all P0–P7, SDA, and SCL pins - meaning it safely accepts input voltages up to 5.5 V even when VDD = 3.3 V. This allows direct connection to 5 V sensors, switches, or LEDs without level shifters. However, the INT output remains referenced to VDD (3.3 V), so host MCU interrupt inputs must be 3.3 V–compatible or include appropriate voltage translation.