Key input function for up to 30 keys (A key scan is performed only when a key is pressed. ) 1/3 duty and 1/4 duty drive schemes can be controlled from serial data. 1/2 bias and 1/3 bias drive schemes can be controlled from serial data. Capable of driving up to 126 segments using 1/3 duty and up to 164 segments using 1/4 duty. Sleep mode and all segments off functions t.