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LED drive and keyboard control chip CH450 |
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| 1. Introduction |
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CH450 is numeric LEDs display drive and keyboard scan control chip.CH450 sets clock surging circuit internal,drives six bits numeric LEDs or forty-eight LEDs automatically.And it carries out forty-eight keys keyboard scan.CH450 exchanges data with MCU via two wires serial and supplies power-up reset signal to MCU. |
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●Set display current drive layer internal,the segment current is no less than 15mA,the word current is no less than 80mA.
●Dynamically display scan control,directly drive six bits numeric LEDs or forty eight LEDs.
●Set forty eight keys keyboard controller internal,basic on 86 matrix keyboard scan.
●Set pull-down resistor internal on the key pressed station, and set eliminate dithering circuit internal.
●Supplies keyboard interrupt active with low-level,supplies key-press release sign bit,to detect key is pressed or released.
●High-speed two wires serial,the speed of clock varies from 0 to 4MHz,compatible with two wires I2C bus,save pins.
●Set clock surge circuit internal,the outside supplies clock or surging equipments is no need,stand against disturbing.
●Set clock surging circuit internal,dont need outside to provide clock or connect surge device,anti-jamming capability is more stronger.
●Set power-on reset internal,supplies reset output active with high-level to MCU.
●Supplies DIP20 and SOP20 package without lead,compatible with RoHS,the function and pins are compatible with CH455 in some parts. |
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| 3. Package |
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CH423DS1.PDF
CH423 English DataSheet
used for MC
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