Overview
The PCA9546A, produced by Texas Instruments, is a quad bidirectional translating switch designed for use with I2C and SMBus systems. This component allows for the control of four downstream I2C/SMBus channels via a single upstream I2C/SMBus interface. It is particularly useful in applications where multiple devices need to be connected to the same I2C bus, and it supports voltage-level translation between different bus voltages, enabling communication between devices operating at different voltage levels (1.8-V, 2.5-V, 3.3-V, and 5-V). The PCA9546A also features an active-low reset input and supports hot insertion, making it versatile and reliable in various system configurations.
Key Specifications
| Specification | Value |
|---|---|
| Package | TSSOP (PW), SOIC (D), TVSOP (DGV), DW, PW, RGV, RGY |
| Pins | 16 |
| Operating Temperature Range | -40°C to 85°C |
| Operating Power-Supply Voltage Range | 2.3 V to 5.5 V |
| Input Voltage Tolerance | 5.5 V |
| Clock Frequency | 0 to 400 kHz |
| Standby Current | Low |
| ESD Protection | 2000-V Human-Body Model, 1000-V Charged-Device Model |
| Latch-Up Performance | Exceeds 100 mA per JESD 78 |
Key Features
- 1-of-4 Bidirectional Translating Switches
- I2C Bus and SMBus Compatible
- Active-Low Reset Input
- Three Address Pins, Allowing up to Eight PCA9546A Devices on the I2C Bus
- Channel Selection Via 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 Standby Current
- 5.5 V Tolerant Inputs
Applications
The PCA9546A is suitable for a variety of applications, including but not limited to:
- Multiplexing I2C/SMBus signals in complex systems
- Voltage translation between different voltage domains
- Hot-swappable I2C/SMBus devices
- Embedded systems requiring multiple I2C/SMBus interfaces
- Industrial automation and control systems
Q & A
- What is the PCA9546A?
The PCA9546A is a quad bidirectional translating switch for I2C and SMBus systems, allowing control of four downstream channels via a single upstream interface. - What are the key features of the PCA9546A?
Key features include I2C and SMBus compatibility, active-low reset input, voltage-level translation, and support for hot insertion. - What is the operating temperature range of the PCA9546A?
The operating temperature range is -40°C to 85°C. - What is the maximum clock frequency supported by the PCA9546A?
The PCA9546A supports clock frequencies up to 400 kHz. - Is the PCA9546A tolerant to high input voltages?
Yes, the PCA9546A has 5.5 V tolerant inputs. - How many devices can be connected to the same I2C bus using the PCA9546A?
Up to eight PCA9546A devices can be connected to the same I2C bus. - What is the purpose of the active-low reset input?
The active-low reset input allows the PCA9546A to recover from a situation where one of the downstream I2C buses is stuck in a low state. - Does the PCA9546A support hot insertion?
Yes, the PCA9546A supports hot insertion. - What types of packages are available for the PCA9546A?
The PCA9546A is available in TSSOP (PW), SOIC (D), TVSOP (DGV), DW, PW, RGV, and RGY packages. - What is the standby current of the PCA9546A?
The PCA9546A has a low standby current.
