English DataSheet of CH455
LED drive and keyboard control chip CH455
CH455 is LED display drive and keyboard scan control chip. It sets clock surge circuit
internally to drive four bits number LED or thirty two LEDs dynamically. And at the same time it
can scan 28-key. CH455 exchanges data with MCU via two wires serial interface of SCL and
● Set display current drive layer internally, the current of segment is no less than 25mA, the
current of word is no less than 160mA.
● Display scan control dynamically, support 8×4 or 7×4, directly drive four bits number LED or
thirty two LEDs.
● Internal limit current, set eight level light control via space percentage.
● Set 28-key keyboard control, based on 7×4 matrix scan..
● Set pull-down resistor internal while key-press, glitter removable.
● Supply keyboard interrupt active with low-level, and supply key-press release token to check
the key is pressed or release.
● High speed two wires serial interface, the speed of clock varies from 0 to 4MHz, compatible
with I2C bus, save pins.
● Set turn on power to reset, 2.7V~5V power.
● Support low exhaust sleep mode to save energy, awoke via press key or command.
● Set clock surge circuit internally, the external clock or surge equipment is not necessary, resister
to be disturbed.
● Supply DIP18, SOP18 and SOP16 package without lead, compatible with RoHS, the function
and pins are part compatible with CH450 .