Overview
The TCA9539RTWR, produced by Texas Instruments, is a 16-bit low-voltage I2C and SMBus I/O expander. This device provides 16 bits of general-purpose parallel input and output (I/O) expansion for the two-line bidirectional I2C bus or SMBus protocol. It operates with a power supply voltage range from 1.65 V to 5.5 V and supports both 100-kHz (I2C Standard mode) and 400-kHz (I2C Fast mode) clock frequencies. The TCA9539 is particularly useful in scenarios where additional I/Os are needed for devices such as switches, sensors, push-buttons, LEDs, and fans.
Key Specifications
| Parameter | Description | Value |
|---|---|---|
| Package Type | TSSOP, WQFN, VQFN | 24 pins |
| Package Size | TSSOP: 7.80 mm × 4.40 mm, WQFN/VQFN: 4.00 mm × 4.00 mm | |
| Supply Voltage (VCC) | 1.65 V to 5.5 V | |
| I2C Clock Frequency | 100 kHz (Standard mode), 400 kHz (Fast mode) | |
| Address Pins | A0 and A1 (hardware selectable) | Allow up to four devices on the same I2C bus |
| Interrupt Output | Open-drain active-low | Generated on INT pin when input port changes state |
| Reset Input | Active-low | Hardware RESET pin and power-on-reset capability |
| ESD Protection | 2000-V Human-Body Model, 1000-V Charged-Device Model | |
| Thermal Resistance | Junction-to-ambient: 108.8°C/W (TSSOP), 43.6°C/W (WQFN), 48.4°C/W (VQFN) |
Key Features
- I2C to Parallel Port Expander
- Low Standby-Current Consumption
- Open-Drain Active-Low Interrupt Output
- Active-Low Reset Input
- 5-V Tolerant I/O Ports
- Compatible With Most Microcontrollers
- 400-kHz Fast I2C Bus
- Input and Output Configuration Register
- Polarity Inversion Register
- Internal Power-on Reset
- No Glitch on Power Up
- Noise Filter on SCL and SDA Inputs
- Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
- Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
- ESD Protection Exceeds JESD 22
Applications
- Servers
- Routers (Telecom Switching Equipment)
- Personal Computers and Smartphones
- Industrial Automation
- I2C GPIO Expansion
Q & A
- What is the TCA9539RTWR used for?
The TCA9539RTWR is used as an I2C and SMBus I/O expander to provide additional I/O ports for microcontrollers and other devices. - What is the operating voltage range of the TCA9539RTWR?
The operating voltage range is from 1.65 V to 5.5 V. - What are the supported I2C clock frequencies?
The device supports 100 kHz (Standard mode) and 400 kHz (Fast mode) clock frequencies. - How many devices can be connected on the same I2C bus?
Up to four devices can be connected on the same I2C bus using the A0 and A1 address pins. - What type of interrupt output does the TCA9539RTWR have?
The device has an open-drain active-low interrupt output. - How can the TCA9539RTWR be reset?
The device can be reset using the hardware RESET pin or by cycling the power supply to trigger a power-on-reset. - What kind of ESD protection does the TCA9539RTWR have?
The device has ESD protection exceeding 2000-V Human-Body Model and 1000-V Charged-Device Model. - What is the thermal resistance of the TCA9539RTWR in different packages?
The thermal resistance varies by package: 108.8°C/W for TSSOP, 43.6°C/W for WQFN, and 48.4°C/W for VQFN. - Can the TCA9539RTWR drive LEDs directly?
Yes, the device has latched outputs with high-current drive capability for directly driving LEDs. - Is the TCA9539RTWR compatible with most microcontrollers?
Yes, it is compatible with most microcontrollers.
