6. Frequently Asked Questions
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It's fully compatible with 5V microcontrollers and can be used for IO expansion.
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Yes, 74HC138N is CMOS-based (low power, faster switching), whereas 74LS138 is TTL-based (higher power consumption).
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Absolutely. It supports demux operation by controlling the enable lines appropriately.
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Yes, 74HC138 is also available in SOIC and TSSOP packages for SMD applications.
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It’s commonly used in address decoding, digital multiplexers, memory mapped IOs, and multi-channel selection.