The TCA9801 is a dual-channel bidirectional buffer intended for I2C bus and SMBus/PMBus systems. It provides bidirectional level shifting (up-translation and down-translation) between low voltages (down to 0.8 V) and higher voltages (1.65 V to 3.6 V). The TCA9801 features an internal current source on the B-side of the device, allowing the removal of external pull-up resistors on the B-side. The current source also provides an improved rise time and ultra-low power consumption.
The TCA9801 is able to provide true buffering (rather than a pass-FET solution) without using a static voltage offset or incremental offset. This means that the VOL on both the A and B sides of the TCA9801 are very low (approximately 0.2 V), helping to eliminate communication issues as a result of fixed VIL thresholds. Another key feature of the TCA9801 is that there are no power sequencing requirements, or power supply dependencies. VCCA can be greater than, less than, or equal to VCCB. This gives the system designer flexibility with how the TCA9801 is used.
The TCA9801 is part of a four device family with varying current source strengths (see the Device Comparison Table).
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|Number of Outputs|
|fSCLK (Max) (MHz)|
|VCC (Max) (V)|
|VCC (Min) (V)|
|Frequency (Max) (kHz)|
|Master Side I2C Bus Capacitance Supported (pF)|
|Slave Side I2C Bus Capacitance Supported (pF)|
|Operating Temperature Range (C)|
| Enable Pin |
Open-Drain I/O Type
Power Save Mode
|-40 to 85|