TI TCA9509MRVHR

TCA9509 是一款适用于 I2C/SMBus 系统的 I2C 总线/SMBus 中继器。The device also provides bidirectional voltage-level translation (up-translation/down-translation) between low voltage (as low as 0.9V) and higher voltage (2.7V to 5.5V) in mixed-mode applications. During level translation, this device extends I2C and similar bus systems without degrading system performance. TCA9509 buffers the serial data (SDA) and serial clock (SCL) signals on the I²C bus, thereby supporting a bus capacitance of 400pF on the B side. This device can also be used to isolate the bus into voltage and capacitance sections. TCA9509 features two types of drivers: A-side drivers and B-side drivers. All inputs and B-side I/Os can withstand overvoltage up to 5.5V. When the device is unpowered (VCCB and/or VCCA = 0V), the A-side I/Os can also withstand overvoltage up to 5.5V. The bus port B drivers are compliant with SMBus I/O levels, while the A-side uses a current sensing mechanism to detect the input or output LOW signal which prevents bus lock-up. The A-side uses a 1 mA current source for pull-up and a 200 Ω pull-down driver. This results in a LOW on the A-side accommodating smaller voltage swings. The output pull-down on the A-side internal buffer LOW is set for approximately 0.2 V, while the input threshold of the internal buffer is set about 50 mV lower than that of the output voltage LOW. When the A-side I/O is driven LOW internally, the LOW is not recognized as a LOW by the input. This prevents a lock-up condition from occurring. The output pull-down on the B-side drives a hard LOW and the input level is set at 0.3 of SMBus or I²C-bus voltage level which enables B side to connect to any other I²C-bus devices or buffer. The TCA9509 drivers are not enabled unless VCCA is above 0.8 V and VCCB is above 2.5 V. The enable (EN) pin can also be used to turn the drivers on and off under system control. Caution should be observed to only change the state of the EN pin when the bus is idle.

• Dual-channel bidirectional buffer compatible with I2C bus and SMBus
• B-side operating supply voltage range: 2.7V to 5.5V
• A-side operating supply voltage range: 0.9V to 5.5V
• Voltage level translation from 0.9V to 5.5V and 2.7V to 5.5V
• Active-high repeater enable input
• No external pull-up resistors required on low-voltage port A
• Open-drain I2C I/O
• 5.5V tolerant I2C and enable inputs
• Mixed-mode signal operation support
• Latch-up-free operation
• Compatible with Standard-mode and Fast-mode I²C devices and multiple controllers
• Supports arbitration and clock stretching on repeater
• Power-off high-impedance I²C bus pins
• Supports 400kHz Fast-mode I²C bus operating speed
• Available in 1.6mm×1.6mm, 0.4mm height, 0.5mm pitch QFN package
• 3mm×3mm industry-standard MSOP package
• Latch-up performance exceeds 100mA per JESD 78 Class II
• ESD protection exceeds JESD 22 specifications
• 2000V Human Body Model (A114-A)
• 1000V Charged Device Model (C101)

• Servers
• Routers (telecom switching equipment)
• Industrial equipment
• Products with multiple I²C targets and/or long PCB traces