The PCA8546 is a peripheral device which generates the drive signals for any multiplexed
LCD containing up to four backplanes, and up to 176 elements. The PCA8546 is
compatible with most microcontrollers and communicates via the two-line bidirectional
I²C-bus (PCA8546A) or a three line unidirectional SPI-bus (PCA8546B). Communication
overheads are minimized using a display RAM with auto-incremented addressing.