3.5 cmos-ttl interfacing

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3.5 CMOS/TTL Interfacing Next Retur n There are several factors to consid er in TTL/CMOS interfacing, the firs t is noise margin; the next factor i s fanout; the last factor is capacit ive loading. V V V V T IL C OL 8 . 0 33 . 0 max max V V V V T IH C OH 0 . 2 84 . 3 min min For example : HC or HCT driving TTL TTL CMOS Consideri ng fanout, an HC or HCT outpu t can dri ve 10 LS or only 2 S-TTL inp uts.

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  • 3.5 CMOS/TTL Interfacing There are several factors to consider in TTL/CMOS interfacing, the first is noise margin; the next factor is fanout; the last factor is capacitive loading. For example : HC or HCT driving TTLConsidering fanout, an HC or HCT output can drive 10 LS or only 2 S-TTL inputs.

  • 3.5 CMOS/TTL Interfacing TTL driving HC or VHC TTL cant drive HC or VHC directly. RP=(3-5)K.