Overview
The PCA9548ADBG4, produced by Texas Instruments, is a low-voltage 8-channel I2C switch with reset functionality. This device is designed to manage multiple I2C buses, allowing for the connection of up to eight downstream I2C channels. It is particularly useful in applications where multiple I2C devices share the same address, enabling the system master to communicate with each device individually through the I2C bus. The PCA9548A supports voltage-level translation between different bus voltages, such as 1.8-V, 2.5-V, 3.3-V, and 5-V, making it versatile for various system configurations.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | TSSOP (PW), SSOP, TVSOP, SOIC, VQFN | - |
| Pins | 24 | - |
| Operating Temperature Range | -40 to 85 | °C |
| Operating Power-Supply Voltage Range | 2.3 to 5.5 | V |
| Clock Frequency | 0 kHz to 400 kHz | - |
| ESD Protection | 2000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model | - |
| Junction-to-Ambient Thermal Resistance | 73.2 to 108.8 | °C/W |
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
- 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 standby current
- 5-V tolerant inputs
- Latch-up performance exceeds 100 mA per JESD 78, Class II
Applications
The PCA9548ADBG4 is suitable for various applications where multiple I2C devices need to be managed. Some common use cases include:
- Resolving I2C slave address conflicts in systems with multiple identical devices.
- Voltage translation in mixed-voltage systems, allowing communication between devices operating at different voltage levels.
- Hot-swappable I2C devices, enabling the addition or removal of devices without system shutdown.
- Complex I2C bus architectures where multiple channels need to be controlled and managed.
Q & A
- What is the primary function of the PCA9548ADBG4?
The PCA9548ADBG4 is an 8-channel I2C switch that allows for the management and selection of multiple I2C channels through the I2C bus.
- What types of packages are available for the PCA9548ADBG4?
The device is available in TSSOP (PW), SSOP, TVSOP, SOIC, and VQFN packages.
- What is the operating temperature range of the PCA9548ADBG4?
The operating temperature range is from -40°C to 85°C.
- Can the PCA9548ADBG4 handle different bus voltages?
- How many PCA9548A devices can be used on the same I2C bus?
Up to eight PCA9548A devices can be used on the same I2C bus, thanks to the three hardware address pins.
- What is the purpose of the active-low reset input?
The active-low reset input allows the system master to reset the PCA9548A in case of a time-out or other improper operation.
- Does the PCA9548ADBG4 support hot insertion?
- What is the clock frequency range of the PCA9548ADBG4?
The clock frequency range is from 0 kHz to 400 kHz.
- What kind of ESD protection does the PCA9548ADBG4 offer?
- How do you select channels on the PCA9548ADBG4?
Channels are selected via the I2C bus by writing to the programmable control register.
