Overview
The TCA9548A-Q1 is an automotive-grade, 8-channel I2C/SMBus switch developed by Texas Instruments. This device is designed to manage multiple I2C buses, resolving address conflicts and enabling communication between devices operating at different voltage levels. It features eight bidirectional translating switches that can be controlled through the I2C bus, allowing for flexible channel selection and voltage-level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses.
The device is qualified to AEC-Q100 (grade 1) standards, making it suitable for automotive applications, and is also functional safety-capable. It includes an active-low reset input, supports hot insertion, and has low quiescent current, making it efficient and reliable in various operational scenarios.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| Operating Supply Voltage | 1.65 | - | 5.25 | V |
| Switch-on Resistance (RON) | 4 | 10 | 25 | Ω (at VCC = 4.5 V to 5.25 V) |
| Switch-on Resistance (RON) | 10 | 25 | 70 | Ω (at VCC = 1.65 V to 1.95 V) |
| Clock Frequency | 0 | - | 400 | kHz |
| Input Voltage Tolerance | -0.5 | - | 7 | V |
| Operating Free-Air Temperature | -40 | - | 85 | °C |
| Junction Temperature (VCC ≤ 3.6 V) | - | - | 125 | °C |
| Junction Temperature (VCC ≤ 5.25 V) | - | - | 90 | °C |
Key Features
- AEC-Q100 (grade 1): Qualified for automotive applications
- Functional Safety-Capable
- 1-to-8 Bidirectional translating switches
- I2C Bus and SMBus compatible
- Active-low reset input
- Three address pins, allowing up to eight TCA9548A-Q1 devices on the I2C bus
- Channel selection through an I2C Bus, in any combination
- Power up with all switch channels deselected
- Low RON switches
- Allows voltage-level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses
- No glitch on power up
- Supports hot insertion
- Low quiescent current
- 5 V tolerant Inputs
- Latch-up performance exceeds 100 mA per JESD 78, class II
Applications
- Infotainment systems
- Body and control systems in automotive applications
- Routers and telecom switching equipment
- Factory automation
- Products with I2C target address conflicts, such as multiple identical temperature sensors
Q & A
- What is the TCA9548A-Q1 used for?
The TCA9548A-Q1 is used to manage multiple I2C buses, resolving address conflicts and enabling communication between devices operating at different voltage levels.
- What are the key features of the TCA9548A-Q1?
Key features include 1-to-8 bidirectional translating switches, I2C Bus and SMBus compatibility, active-low reset input, and voltage-level translation between 1.8 V, 2.5 V, 3.3 V, and 5 V buses.
- What is the operating supply voltage range of the TCA9548A-Q1?
The operating supply voltage range is from 1.65 V to 5.25 V.
- Is the TCA9548A-Q1 suitable for automotive applications?
- What is the maximum clock frequency supported by the TCA9548A-Q1?
The maximum clock frequency supported is 400 kHz.
- Does the TCA9548A-Q1 support hot insertion?
- How many devices can be connected on the I2C bus using the TCA9548A-Q1?
- What is the purpose of the active-low reset input on the TCA9548A-Q1?
The active-low reset input allows the system controller to reset the device in case of a time-out or improper operation.
- Are the inputs of the TCA9548A-Q1 5 V tolerant?
- What is the typical on-resistance (RON) of the switches in the TCA9548A-Q1?
The typical on-resistance (RON) varies depending on the supply voltage but is typically around 10 Ω at VCC = 4.5 V to 5.25 V.
