Overview
The PCA9548A, also known as PCA9548ARGER, is a low-voltage 8-channel I2C switch with reset, manufactured by Texas Instruments. This device is designed to manage multiple I2C or SMBus devices on a single bus, resolving address conflicts and enabling the use of multiple identical devices in the same system. The PCA9548A features bidirectional translating switches that can be controlled via the I2C bus, allowing for flexible and efficient communication between different voltage-level devices.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Number of Channels | 8 | - |
| Operating Power-Supply Voltage Range | 2.3 V to 5.5 V | V |
| Clock Frequency | 0 kHz to 400 kHz | kHz |
| Maximum Operating Temperature | 85 | °C |
| Package Options | SSOP (24), TVSOP (24), SOIC (24), TSSOP (24), VQFN (24) | - |
| RON (On-Resistance) | 20 Ω | Ω |
| Propagation Delay Time | 0.3 ns (CL = 15 pF), 1 ns (CL = 50 pF) | ns |
| ESD Protection | 2000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model | V |
Key Features
- 1-of-8 bidirectional translating switches
- I2C bus and SMBus compatible
- Active-low reset input
- Three hardware address pins for use of up to eight PCA9548A devices on the I2C bus
- Channel selection via I2C bus
- Power-up with all switch channels deselected
- Low RON switches
- 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 standby current
- 5-V tolerant inputs
- Latch-up performance exceeds 100 mA per JESD 78, Class II
Applications
- Servers
- Routers (Telecom Switching Equipment)
- Factory Automation
- Products with I2C slave address conflicts (e.g., multiple identical temperature sensors)
Q & A
- What is the PCA9548A used for?
The PCA9548A is used to manage multiple I2C or SMBus devices on a single bus, resolving address conflicts and enabling the use of multiple identical devices in the same system.
- How many channels does the PCA9548A have?
The PCA9548A has 8 bidirectional translating switches.
- What is the operating voltage range of the PCA9548A?
The operating power-supply voltage range is from 2.3 V to 5.5 V.
- What is the maximum clock frequency supported by the PCA9548A?
The maximum clock frequency supported is 400 kHz.
- Does the PCA9548A support voltage-level translation?
- What are the package options available for the PCA9548A?
The PCA9548A is available in SSOP (24), TVSOP (24), SOIC (24), TSSOP (24), and VQFN (24) packages.
- How does the PCA9548A handle reset conditions?
The PCA9548A has an active-low reset input. Asserting the RESET input causes the device to reset and initialize the I2C/SMBus state machine without powering down the part.
- Is the PCA9548A suitable for hot insertion?
- What is the ESD protection level of the PCA9548A?
The PCA9548A has ESD protection exceeding 2000-V Human-Body Model, 200-V Machine Model, and 1000-V Charged-Device Model.
- What are some common applications of the PCA9548A?
