CH455 Datasheet - ETC

CH455 LED drive and keyboard control chip

Positive power, the persistent current is no less than 150mA Public ground, the persistent current is no less than 150mA Segment driver of LEDs, active with high level, Keyboard scan input, active with high level, with pull-down resistor Radix point segment output of LED, active with high level, Key.

English DataSheet of CH455 1 LED drive and keyboard control chip CH455 English DataSheet Version:1C http://wch.cn 1. Introduction 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 SDA.. MCU etc SCL SDA INT# CH455 (broken line is optional) SEG7～SEG0 SEG6 ～ 7×4 matrix 28 k.

CH455 Features

* 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

CH455-ETC.pdf