TCA6408 I²C I/O Expander
The TCA6408, an 8-bit I²C I/O expander with interrupt and reset, supports operating voltages down to 1.65 V which makes it suitable for next-generation microprocessors and microcontrollers.
The major benefit of this I²C I/O expander is its wide VCC range. It can operate from 1.65 to 5.5 V (P port side and SDA/SCL side). This allows the TCA6408 to interface with nextgeneration microprocessors and microcontrollers on the SDA/SCL side, where supply levels are dropping down to conserve power.
The bidirectional voltage level translation in
the TCA6408 is provided through VCCI. VCCI should be connected to the VCC of the external SCL/SDA lines. This indicates the VCC level of the I²C bus to the TCA6408. The voltage level on the P port of the TCA6408 is determined by VCCP.
The TCA6408 consists of one 8-bit configuration
(input or output selection), input, output and polarity inversion (active high) register. At power on, the I/Os are configured as inputs.
However, the system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding input or output register. The polarity of the input port register can be inverted with the polarity inversion register.
All registers can be read by the system master. The system master can reset the TCA6408
in the event of a timeout or other improper operation by asserting a low in the RESET input. The power-on reset puts the registers in their default state and initializes the I²C/SMBus state machine. The RESET pin causes the same reset/initialization to occur without depowering the part.
Additional Information
For detailed specifications please contact your next SPOERLE Branch Office or visit
| Download: I²C-Selection-Guide |
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