Overview
The PCA9554APWR, produced by Texas Instruments, is an 8-bit I2C/SMBus I/O expander designed to provide additional I/O ports for microcontrollers. This device is particularly useful in applications where the microcontroller's I/O capabilities are limited. It operates within a power-supply voltage range of 2.3 V to 5.5 V, making it versatile for various system designs.
The PCA9554APWR features an open-drain active-low interrupt output, allowing it to notify the microcontroller of changes in its ports without continuous polling. This enhances system efficiency and reduces the load on the microcontroller.
Key Specifications
| Parameter | Description | Value |
|---|---|---|
| Operating Power-Supply Voltage Range | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
| I2C Bus Speed | 400 kHz | 400 kHz |
| Number of I/O Ports | 8-bit | 8 |
| Interrupt Output | Open-Drain Active-Low | Open-Drain Active-Low |
| Hardware Address Pins | 3 (A0, A1, A2) | 3 |
| Package Type | TSSOP (PW) with 16 pins | TSSOP (PW) with 16 pins |
| ESD Protection | 2000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model | 2000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model |
| Latch-Up Performance | Exceeds 100 mA per JESD 78, Class II | Exceeds 100 mA per JESD 78, Class II |
Key Features
- I2C to Parallel Port Expander: Expands the I/O capabilities of a microcontroller.
- Open-Drain Active-Low Interrupt Output: Allows the device to notify the microcontroller of port changes without continuous polling.
- Operating Power-Supply Voltage Range of 2.3 V to 5.5 V: Versatile for various system designs.
- 5-V Tolerant I/Os: Compatible with 5V systems.
- 400-kHz Fast I2C Bus: Supports high-speed I2C communication.
- Three Hardware Address Pins: Allows up to eight devices on the same I2C/SMBus.
- Input/Output Configuration Register and Polarity Inversion Register: Provides flexibility in configuring the I/O ports.
- Internal Power-On Reset and No Glitch On Power Up: Ensures stable operation during power-up.
- Latched Outputs With High-Current Drive Capability: Can directly drive LEDs with high current and low current consumption.
Applications
- Embedded Systems: Useful in expanding the I/O capabilities of microcontrollers in embedded systems.
- Industrial Automation: Can be used to control and monitor various industrial devices.
- Consumer Electronics: Suitable for use in consumer electronics where additional I/O ports are needed.
- Automotive Systems: Can be integrated into automotive systems for expanded I/O functionality.
Q & A
- What is the operating voltage range of the PCA9554APWR?
The PCA9554APWR operates within a power-supply voltage range of 2.3 V to 5.5 V.
- How many I/O ports does the PCA9554APWR provide?
The PCA9554APWR provides 8-bit I/O ports, which means it has 8 I/O ports.
- What is the purpose of the interrupt output on the PCA9554APWR?
The interrupt output allows the device to notify the microcontroller of changes in its ports without continuous polling.
- How many devices can be connected on the same I2C/SMBus using the PCA9554APWR?
Up to eight devices can be connected on the same I2C/SMBus using the three hardware address pins (A0, A1, A2).
- What is the maximum current drive capability of the PCA9554APWR's outputs?
The outputs have high-current drive capability, with each I/O limited to a maximum of 25 mA and the total current sourced by all I/Os limited to 85 mA.
- Is the PCA9554APWR compatible with the PCF8574?
The PCA9554APWR is pin-to-pin and I2C address compatible with the PCF8574, but software changes are required due to the enhancements in the PCA9554APWR.
- What type of ESD protection does the PCA9554APWR offer?
The PCA9554APWR offers ESD protection exceeding 2000-V Human-Body Model, 200-V Machine Model, and 1000-V Charged-Device Model.
- What is the package type of the PCA9554APWR?
The PCA9554APWR comes in a TSSOP (PW) package with 16 pins.
- Can the PCA9554APWR directly drive LEDs?
Yes, the PCA9554APWR's outputs have high-current drive capability and can directly drive LEDs.
- Does the PCA9554APWR have internal power-on reset?
Yes, the PCA9554APWR has an internal power-on reset and ensures no glitch on power up.
