Overview
The PCA9555DBQR, produced by Texas Instruments, is a 16-bit I2C and SMBus I/O expander designed to provide remote I/O expansion for most microcontroller families. This device operates within a voltage range of 2.3-V to 5.5-V and is compatible with the I2C interface, utilizing serial clock (SCL) and serial data (SDA) lines. It features two 8-bit configuration registers, input port, output port, and polarity inversion registers, allowing for flexible configuration of the I/Os as either inputs or outputs. The PCA9555 is particularly useful in applications where additional GPIO ports are needed, enhancing the capability of the host microcontroller.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Voltage Range | 2.3-V to 5.5-V | V |
| I2C Bus Frequency | Up to 400 kHz | kHz |
| Number of I/O Bits | 16 | - |
| Interrupt Output | Open-Drain Active-Low | - |
| Standby Current Consumption | 1 μA Max | μA |
| ESD Protection | 2000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model | V |
| Packages Available | SSOP (24), QSOP (24), TVSOP (24), SOIC (24), TSSOP (24), QFN (24) | - |
| Junction-to-Ambient Thermal Resistance (RθJA) | 48.4 to 108.8 °C/W (depending on package) | °C/W |
Key Features
- I2C to Parallel Port Expander with up to 400 kHz bus frequency.
- Open-Drain Active-Low Interrupt Output for notification of input changes.
- 5-V Tolerant I/O Ports for compatibility with a wide range of microcontrollers.
- Three hardware address pins (A0, A1, A2) allowing up to eight devices to share the same I2C bus or SMBus.
- Polarity Inversion Register for flexible input/output configuration.
- Latched Outputs with High-Current Drive Capability for directly driving LEDs.
- Low Standby-Current Consumption of 1 μA Max for power-efficient operation.
- ESD Protection exceeding JESD 22 and JESD 78 standards for robust reliability.
Applications
- Servers and Routers (Telecom Switching Equipment)
- Personal Computers and Personal Electronics
- Industrial Automation Equipment
- Products with GPIO-Limited Processors
Q & A
- What is the operating voltage range of the PCA9555? The PCA9555 operates within a voltage range of 2.3-V to 5.5-V.
- What is the maximum I2C bus frequency supported by the PCA9555? The PCA9555 supports up to 400 kHz I2C bus frequency.
- How many I/O bits does the PCA9555 provide? The PCA9555 provides 16 I/O bits.
- What type of interrupt output does the PCA9555 have? The PCA9555 has an open-drain active-low interrupt output.
- What is the standby current consumption of the PCA9555? The standby current consumption is 1 μA Max.
- What types of packages are available for the PCA9555? The PCA9555 is available in SSOP, QSOP, TVSOP, SOIC, TSSOP, and QFN packages.
- How many devices can share the same I2C bus using the PCA9555? Up to eight devices can share the same I2C bus or SMBus using the three hardware address pins.
- Does the PCA9555 support polarity inversion for the input ports? Yes, the PCA9555 supports polarity inversion for the input ports through the Polarity Inversion Register.
- What is the ESD protection level of the PCA9555? The PCA9555 exceeds JESD 22 and JESD 78 standards for ESD protection.
- Can the PCA9555 directly drive LEDs? Yes, the PCA9555 has latched outputs with high-current drive capability for directly driving LEDs.
