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ELM408 Rotary Decoder - 2 wire Interface
Description
The ELM408 is an 8 pin integrated circuit that is used to convert the output from a rotary encoder into two signals (chip select, and up/down) that can be used to control various devices. The low power CMOS technology used ensures that only a very small current is required over the entire 2.0 to 5.5 volt operating range. There is no need for external filtering or debounce circuits with the ELM408, as this is all performed within the integrated circuit. After debouncing the encoder signals, the ELM408 determines the direction of shaft rotation, and then generates the appropriate outputs. A write sequence can also be generated if the Write Enable input is at a high level when the outputs are generated.