Overview
The PCA9554DB, produced by Texas Instruments, is an 8-bit I2C and SMBus I/O expander designed for remote I/O expansion in various microcontroller-based systems. It operates within a voltage range of 2.3 V to 5.5 V, making it versatile for different application environments. The device features an open-drain interrupt output and supports up to 16 devices on the same I2C/SMBus, thanks to its programmable I2C addresses using three hardware pins (A0, A1, and A2).
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC Operating Voltage | 2.3 | - | 5.5 | V |
| ICC Operating Current (fscl = 400 kHz, No load) | - | 104 | 175 | μA |
| ICC Operating Current (fscl = 100 kHz, No load) | - | 60 | 150 | μA |
| ICC Standby Current | - | - | 1 | μA |
| Output High Voltage (VCC - VOH) at IOH = 8 mA | - | - | 0.4 | V |
| Input Data Hold Time | 1 | - | - | μs |
| I2C Bus Frequency | - | - | 400 | kHz |
Key Features
- 8-bit I/O expander with I2C and SMBus interface
- Open-drain interrupt output to indicate input state changes
- Programmable I2C addresses using three hardware pins (A0, A1, A2) allowing up to 16 devices on the same bus
- Latched outputs with high-current drive capability for directly driving LEDs
- Polarity Inversion register to invert the polarity of the Input Port register
- Weak pull-up to VCC on all I/O pins at power-on, configurable as inputs or outputs
- ESD protection exceeding 2000-V Human-Body Model, 200-V Machine Model, and 1000-V Charged-Device Model
- Low standby current consumption
Applications
- Servers and data centers for remote I/O expansion
- Industrial automation and control systems
- Consumer electronics requiring I/O expansion
- Automotive systems for distributed I/O control
- Medical devices needing remote I/O capabilities
Q & A
- What is the operating voltage range of the PCA9554DB?
The PCA9554DB operates within a voltage range of 2.3 V to 5.5 V.
- How many devices can be connected on the same I2C/SMBus?
Up to 16 devices can be connected on the same I2C/SMBus, with eight devices of each PCA9554 and PCA9554A type.
- What is the purpose of the open-drain interrupt output?
The open-drain interrupt output is used to indicate to the system master that an input state has changed.
- Can the I/O pins be configured as inputs or outputs?
- What is the maximum I2C bus frequency supported by the PCA9554DB?
The PCA9554DB supports an I2C bus frequency of up to 400 kHz.
- Does the PCA9554DB have ESD protection?
- How are the I2C addresses programmed for multiple devices?
The I2C addresses are programmed using three hardware pins (A0, A1, and A2).
- What is the standby current consumption of the PCA9554DB?
The standby current consumption is typically 1 μA.
- Can the PCA9554DB drive LEDs directly?
- Is the PCA9554DB compatible with other microcontrollers?
