The TLC6989 is an SPI-compatible connectivity between an SPI and a Continuous Clock Serial Interface (CCSI). The device can drive any number of cascaded LED drivers of the TLC698x family. The maximum number of cascaded devices is limited by the LED driver.

The TLC6989 uses an internal oscillator and clock divider to provide a programmable continuous clock frequency for the CCSI. Data words received by the SPI peripheral are forwarded by the CCSI controller where the data is aligned to the continuous clock. Data words received by the CCSI peripheral can be stored by the TLC6989 and read by the Controller using SPI. The continuous clock incorporates a programmable pseudo-random jitter (spread spectrum) feature to reduce EMI emissions.

The TLC6989 automatically inserts the required start bit and check bits when forwarding the data words received by SPI peripheral. For data words received by the CCSI peripheral, the TLC6989 automatically analyses the check bits and reports when an error is detected. When the data words are stored for reading by SPI, the start bit and check bits are removed from the data string.

The TLC6989 automatically inserts the required end byte when forwarding the data words received by SPI peripheral to make sure that different SPI commands are recognized as different CCSI commands. When the data words are stored for reading by SPI, the end byte is removed from the data string.

The SPI peripheral of TLC6989 shifts in data using the rising edge of the clock. For the CCSI the data is shifted out by TLC6989 at both the rising and falling edge of the continuous clock.