Overview
The TCA8418RTWR from Texas Instruments is a keypad scan device designed with integrated ESD protection. This IC operates within a voltage range of 1.65 V to 3.6 V and features 18 general-purpose inputs/outputs (GPIO) that can support up to 80 keys via the I²C interface. The device includes a 10-byte FIFO to store key-press and release events, an open-drain active-low interrupt output, and integrated debounce functionality. It is particularly useful in applications requiring robust keypad scanning and GPIO expansion.
Key Specifications
| Parameter | Description |
|---|---|
| Manufacturer | Texas Instruments |
| Part Number | TCA8418RTWR |
| Package | WQFN-24-EP (4x4) |
| Operating Voltage Range | 1.65 V to 3.6 V |
| Operating Temperature Range | -40°C to 85°C |
| I²C Interface Speed | Up to 1 MHz |
| GPIOs | 18 general-purpose inputs/outputs |
| FIFO Capacity | 10 bytes for key-press and release events |
| Interrupt Output | Open-drain active-low |
| Debounce Time | 50 μs |
| ESD Protection | 2000-V Human Body Model, 1000-V Charged Device Model |
| RoHS Compliance | Yes |
Key Features
- Operating power-supply voltage range of 1.65 V to 3.6 V
- Supports up to 80 buttons with 18 GPIOs
- Supports QWERTY keypad operation plus GPIO expansion
- Low standby (idle) current consumption: 3 μA
- Supports 1-MHz fast mode I²C bus
- 10-byte FIFO to store key-press and release events
- Open-drain active-low interrupt output
- Integrated debounce time of 50 μs
- Schmitt-trigger action for better switching noise immunity at SCL and SDA inputs
- Latch-up performance exceeds 200 mA per JESD 78, Class II
- ESD protection exceeds JESD 22 on all 18 GPIO pins and non-GPIO pins
Applications
The TCA8418RTWR is suitable for various applications requiring robust keypad scanning and GPIO expansion, such as:
- Industrial control panels
- Medical devices
- Consumer electronics with keypads (e.g., remote controls, calculators)
- Automotive systems requiring keypad input
- Point-of-sale terminals and other interactive devices
Q & A
- What is the operating voltage range of the TCA8418RTWR?
The operating voltage range is from 1.65 V to 3.6 V.
- How many GPIOs does the TCA8418RTWR have?
The device has 18 general-purpose inputs/outputs (GPIO).
- What is the maximum speed of the I²C interface on the TCA8418RTWR?
The I²C interface supports speeds up to 1 MHz.
- What is the capacity of the FIFO in the TCA8418RTWR?
The FIFO can store up to 10 bytes of key-press and release events.
- Does the TCA8418RTWR have integrated ESD protection?
Yes, it has integrated ESD protection exceeding JESD 22 standards.
- What is the debounce time of the TCA8418RTWR?
The integrated debounce time is 50 μs.
- Can the TCA8418RTWR support QWERTY keypad operation?
Yes, it supports QWERTY keypad operation along with GPIO expansion.
- What is the standby current consumption of the TCA8418RTWR?
The standby (idle) current consumption is 3 μA.
- Is the TCA8418RTWR RoHS compliant?
Yes, the device is RoHS compliant.
- What is the package type of the TCA8418RTWR?
The package type is WQFN-24-EP (4x4).
