Overview
The PCA9306, produced by Texas Instruments, is a dual bidirectional I2C and SMBus voltage-level translator. This device is designed to facilitate voltage translation between different voltage domains without the need for a direction pin. It operates with reference supply voltages ranging from 1.2 V to 3.3 V for VREF1 and 1.8 V to 5.5 V for VREF2, allowing bidirectional data flow between ports when the enable (EN) input is high. When EN is low, the translator switch is off, and a high-impedance state exists between the ports, enabling isolation between different bus frequencies.
Key Specifications
| Parameter | Min | Max | Unit |
|---|---|---|---|
| VREF1 DC reference voltage range | -0.5 | 7 | V |
| VREF2 DC reference bias voltage range | -0.5 | 7 | V |
| Input voltage range | -0.5 | 7 | V |
| Input/output voltage range | -0.5 | 7 | V |
| Continuous channel current | 128 | mA | |
| Maximum junction temperature | 125 | °C | |
| Storage temperature range | -65 | 150 | °C |
| Operating ambient temperature | -40 | 85 | °C |
| Propagation delay (tPLH, tPHL) | 0 | 1.5 | ns |
Key Features
- 2-bit bidirectional translator for SDA and SCL lines in mixed-mode I2C applications.
- I2C and SMBus compatible.
- Less than 1.5-ns maximum propagation delay to accommodate standard-mode and fast-mode I2C devices.
- Allows voltage-level translation between 1.2 V and 5 V without the use of a direction pin.
- Lockup-free operation for isolation when EN is low.
- Flow-through pinout for ease of printed-circuit-board trace routing.
- ESD protection exceeds JESD 22 – 2000-V Human-body model and 1000-V Charged-device model.
- Latch-up performance exceeds 100 mA per JESD 78, class II.
Applications
- I2C, SMBus, PMBus, MDIO, UART, low-speed SDIO, GPIO, and other two-signal interfaces.
- Servers.
- Routers (telecom switching equipment).
- Personal Computers.
- Industrial Automation.
- Remote board insertion to backplane with I2C lines.
Q & A
- What is the PCA9306 device used for?
The PCA9306 is a dual bidirectional I2C and SMBus voltage-level translator used to facilitate voltage translation between different voltage domains.
- What are the operating voltage ranges for VREF1 and VREF2?
VREF1 operates from 1.2 V to 3.3 V, and VREF2 operates from 1.8 V to 5.5 V.
- How does the enable (EN) input affect the device?
When EN is high, the translator switch is ON, allowing bidirectional data flow. When EN is low, the translator switch is off, and a high-impedance state exists between ports.
- What is the maximum propagation delay of the PCA9306?
The maximum propagation delay is less than 1.5 ns.
- What types of applications can the PCA9306 be used in?
The PCA9306 can be used in I2C, SMBus, PMBus, MDIO, UART, low-speed SDIO, GPIO, and other two-signal interfaces, as well as in servers, routers, personal computers, and industrial automation.
- How does the PCA9306 handle ESD protection?
The PCA9306 has ESD protection that exceeds JESD 22 – 2000-V Human-body model and 1000-V Charged-device model.
- Can the PCA9306 be used to isolate different bus frequencies?
Yes, the PCA9306 can be used to isolate a 400-kHz bus from a 100-kHz bus by controlling the EN pin.
- What are the available package options for the PCA9306?
The PCA9306 is available in SSOP (8), VSSOP (8), X2SON (8), and DSBGA (8) packages.
- How does the PCA9306 support remote board insertion to a backplane?
The PCA9306 can be disabled while making the connection and then enabled once the remote board is powered on and the buses on both sides are IDLE, preventing data corruption or unintended pulses.
- Can the PCA9306 be used as a switch?
Yes, the PCA9306 can be used as a switch when VREF1 is equal to VREF2, and the enable is controlled by a GPIO.
