Overview
The PCAL6408AEX1Z is an 8-bit general-purpose I/O expander manufactured by NXP USA Inc. This component is designed to provide remote I/O expansion for most microcontroller families via the I²C-bus interface. It is a pin-to-pin replacement for the PCA6408A, with the added benefit of having all I/O interrupts masked at power-up, preventing spurious interrupts during board bring-up. The PCAL6408AEX1Z supports low-voltage translation and is suitable for mixed signal environments where communication between incompatible I/O voltages is necessary.
Key Specifications
| Parameter | Description |
|---|---|
| Number of Bits | 8-bit |
| Interface | I²C-bus/SMBus |
| Supply Voltage Range | 1.65 V to 5.5 V (dual power rail) |
| Output Drive Strength | Programmable |
| Output Configuration | Bank selectable push-pull or open-drain output stages |
| Interrupt Features | Maskable interrupt, interrupt status register, open-drain interrupt output |
| Pull-up/Pull-down Resistors | Programmable |
| ESD Protection | 2000 V Human-Body Model, 1000 V Charged-Device Model |
| Operating Temperature Range | -40°C to +85°C |
| Packages | HVQFN16, TSSOP16, XQFN16, XFBGA16, X2QFN16 |
Key Features
- Low-voltage translating capability, allowing communication between different voltage levels.
- Programmable output drive strength and pull-up/pull-down resistors.
- Maskable interrupt and interrupt status register for efficient interrupt handling.
- Open-drain interrupt output for notifying the system master of input state changes.
- Input latch feature to hold input pin states until the master can service the interrupt.
- Polarity inversion register to save external logic gates.
- 25 mA sink capabilities for directly driving LEDs.
- Software backward compatible with PCA6408A, with interrupts disabled at power-up.
Applications
- Battery-powered mobile applications for interfacing to sensors, push buttons, and keypads.
- Mixed signal environments requiring communication between incompatible I/O voltages.
- Industrial and IoT applications where additional I/Os are needed with minimal interconnections.
- Automotive systems requiring robust and reliable I/O expansion.
Q & A
- What is the PCAL6408AEX1Z used for?
The PCAL6408AEX1Z is used as an 8-bit general-purpose I/O expander to provide remote I/O expansion for most microcontroller families via the I²C-bus interface.
- What are the key differences between the PCAL6408A and PCA6408A?
The PCAL6408A powers up with all I/O interrupts masked, preventing spurious interrupts during board bring-up, and is software backward compatible with the PCA6408A.
- What is the supply voltage range for the PCAL6408AEX1Z?
The supply voltage range is 1.65 V to 5.5 V on a dual power rail.
- What types of packages are available for the PCAL6408AEX1Z?
The component is available in HVQFN16, TSSOP16, XQFN16, XFBGA16, and X2QFN16 packages.
- Does the PCAL6408AEX1Z support programmable pull-up and pull-down resistors?
- What is the purpose of the interrupt features in the PCAL6408AEX1Z?
The interrupt features, including the maskable interrupt and interrupt status register, are designed to efficiently handle input state changes and notify the system master without continuous I²C-bus communication.
- Can the PCAL6408AEX1Z drive LEDs directly?
- What is the operating temperature range for the PCAL6408AEX1Z?
The operating temperature range is -40°C to +85°C.
- Does the PCAL6408AEX1Z have ESD protection?
- How does the PCAL6408AEX1Z handle input state changes?
The input latch feature holds the input pin state until the master can service the interrupt, minimizing the host's interrupt service response time.
