Overview
The PCA9546ADR, produced by Texas Instruments, is a quad bidirectional translating switch designed for I2C and SMBus applications. This component allows for the fan-out of a single upstream I2C/SMBus pair to four downstream pairs or channels, enabling flexible and efficient communication between multiple devices on the same bus. The PCA9546ADR supports voltage-level translation between different bus voltages, making it compatible with a wide range of devices operating at 1.8-V, 2.5-V, 3.3-V, and 5-V levels.
Key Specifications
| Parameter | Value |
|---|---|
| Package | SOIC (D) - 16 pins |
| Operating Power-Supply Voltage Range | 2.3 V to 5.5 V |
| Operating Temperature Range | -40°C to 85°C |
| Clock Frequency | 0 to 400 kHz |
| Input Voltage Tolerance | 5.5 V tolerant inputs |
| ESD Protection | 2000-V Human-Body Model, 1000-V Charged-Device Model |
| Address Pins | Three address pins, allowing up to eight devices on the I2C bus |
| Reset Input | Active-low reset input |
Key Features
- 1-of-4 bidirectional translating switches
- I2C bus and SMBus compatible
- Active-low reset input
- Channel selection via I2C bus in any combination
- 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
- Latch-up performance exceeds 100 mA per JESD 78
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 PCA9546ADR used for? The PCA9546ADR is used as a quad bidirectional translating switch for I2C and SMBus applications, allowing multiple devices to share the same bus.
- What is the operating voltage range of the PCA9546ADR? The operating power-supply voltage range is from 2.3 V to 5.5 V.
- How many devices can be connected on the same I2C bus using the PCA9546ADR? Up to eight PCA9546ADR devices can be connected on the same I2C bus.
- What is the purpose of the active-low reset input? The active-low reset input allows the PCA9546ADR to recover from a situation where one of the downstream I2C buses is stuck in a low state.
- Does the PCA9546ADR support voltage-level translation? Yes, it supports voltage-level translation between 1.8-V, 2.5-V, 3.3-V, and 5-V buses.
- What is the clock frequency range of the PCA9546ADR? The clock frequency range is from 0 to 400 kHz.
- Is the PCA9546ADR tolerant to high input voltages? Yes, all I/O pins are 5.5-V tolerant.
- What kind of ESD protection does the PCA9546ADR offer? It offers ESD protection exceeding 2000-V Human-Body Model and 1000-V Charged-Device Model.
- Can the PCA9546ADR be used in hot insertion scenarios? Yes, it supports hot insertion.
- What is the typical standby current of the PCA9546ADR? It has a low standby current.
