Overview
The TCA9548A, produced by Texas Instruments, is an 8-channel bidirectional translating switch designed for I2C and SMBus applications. This device allows for the control of up to eight downstream I2C/SMBus channels through a single upstream I2C/SMBus pair. It is particularly useful in resolving I2C target address conflicts and enabling communication between devices operating at different voltage levels. The TCA9548A features an active-low reset input, power-up with all switch channels deselected, and supports hot insertion. It operates within a power-supply voltage range of 1.65V to 5.5V and is compatible with various bus voltages, including 1.8V, 2.5V, 3.3V, and 5V.
Key Specifications
| Parameter | Description |
|---|---|
| Number of Channels | 8 bidirectional translating switches |
| Bus Compatibility | I2C Bus and SMBus compatible |
| Reset Input | Active-low reset input |
| Address Pins | Three address pins (A0, A1, A2) |
| Channel Selection | Channel selection through I2C Bus, in any combination |
| Power-Up State | Power up with all switch channels deselected |
| RON Switches | Low RON switches |
| Voltage Translation | Allows voltage-level translation between 1.8V, 2.5V, 3.3V, and 5V buses |
| Power Supply Voltage | Operating power-supply voltage range of 1.65V to 5.5V |
| Input Tolerance | 5-V Tolerant inputs |
| Clock Frequency | 0 to 400kHz Clock frequency |
| ESD Protection | ESD Protection exceeds JESD 22: ±2000V Human-body model, 200V Machine model, ±1000V Charged-device model |
| Package | 24-pin VQFN (RGE) package |
Key Features
- 1-to-8 bidirectional translating switches
- I2C Bus and SMBus compatible
- Active-low reset input
- Three address pins, allowing up to eight TCA9548A devices on the I2C bus
- Channel selection through I2C Bus, in any combination
- Power up with all switch channels deselected
- Low RON switches
- Allows voltage-level translation between 1.8V, 2.5V, 3.3V, and 5V buses
- No glitch on power up
- Supports hot insertion
- Low standby current
- Operating power-supply voltage range of 1.65V to 5.5V
- 5-V Tolerant inputs
- 0 to 400kHz Clock frequency
- Latch-up performance exceeds 100mA Per JESD 78, class II
- ESD Protection exceeds JESD 22
Applications
- Servers
- Routers (telecom switching equipment)
- Factory automation
- Products with I2C slave address conflicts (such as multiple, identical temperature sensors)
- Communications & Networking
Q & A
- What is the primary function of the TCA9548A?
The TCA9548A is an 8-channel bidirectional translating switch that allows control of up to eight downstream I2C/SMBus channels through a single upstream I2C/SMBus pair.
- What is the operating voltage range of the TCA9548A?
The operating power-supply voltage range of the TCA9548A is from 1.65V to 5.5V.
- How many address pins does the TCA9548A have?
The TCA9548A has three address pins (A0, A1, A2), allowing up to eight devices on the I2C bus.
- What is the purpose of the active-low reset input?
The active-low reset input allows the system master to reset the TCA9548A in the event of a time-out or other improper operation.
- Does the TCA9548A support voltage translation?
Yes, the TCA9548A allows voltage-level translation between 1.8V, 2.5V, 3.3V, and 5V buses.
- What is the maximum clock frequency supported by the TCA9548A?
The TCA9548A supports a clock frequency of up to 400kHz.
- Is the TCA9548A compatible with SMBus?
Yes, the TCA9548A is both I2C Bus and SMBus compatible.
- What is the package type of the TCA9548A?
The TCA9548A is available in a 24-pin VQFN (RGE) package.
- Does the TCA9548A support hot insertion?
Yes, the TCA9548A supports hot insertion.
- What kind of ESD protection does the TCA9548A offer?
The TCA9548A offers ESD protection that exceeds JESD 22 standards, including ±2000V Human-body model, 200V Machine model, and ±1000V Charged-device model.
