ls hct
http://design.stanford.edu/spdl/ME218a/logic/which_is_best.html
http://www.interfacebus.com/voltage_threshold.html
http://www.cybermike.net/reference/74series.html
Device Families:
TTL (74xx) True TTL
74L Low power
74S Schottky
74H High speed
74LS Low power - Schottky
74AS Advanced - Schottky
74ALS Advanced - Low power - Schottky
74F(AST) Fast - (Advanced - Schottky)
74C CMOS...................check Vcc levels
74HC (U) High speed - CMOS (Unbuffered output)
74HCT High speed - CMOS - TTL inputs
74AHC Advanced - High speed - CMOS
74AHCT Advanced - High speed - CMOS - TTL inputs
74FCT (-A) Fast - CMOS - TTL inputs (speed variations)
74FCT (-T, -AT) Fast - CMOS - TTL inputs (speed variations)
74AC Advanced - CMOS
74ACT Advanced - CMOS - TTL inputs
74FACT AC, ACT (Q) series
74ACQ Advanced - CMOS - Quiet outputs
74ACTQ Advanced - CMOS - TTL inputs - Quiet outputs
Bus Driver Families
74ABT Advanced - BiCMOS - Technology
74ABTE ABT - Enhanced Transceiver Logic
74ABTH Advanced - BiCMOS - Technology - bus Hold
74BCT BiCMOS - TTL inputs
74BTL Backplane - Transceiver - Logic
74GTL Gunning - Transceiver - Logic
74GTLP GTL Plus
Low Voltage Families
74ALB Advanced - Low Voltage - BiCMOS
74LV (U) Low - Voltage (Unbuffered output)
74LVC (R) (U) LV - CMOS (damping Resistor)(Unbuffered output)
74LVCH Low - Voltage - CMOS - bus Hold
74ALVC Advanced - Low - Voltage - CMOS
74LVT (R) (U) LV - TTL (damping Resistor(Unbuffered output)
74LVTZ Low - Voltage - TTL - High Impedance power-up
74ALVC (R) ALV - CMOS (bus Hold) (damping Resistor)
74ALVCH Advanced - Low - Voltage - CMOS - bus Hold
74LCX LV - CMOS (operates with 3v & 5v supplies)
74VCX LV - CMOS (operates with 1.8v & 3.6v supplies
4000 True CMOS (non-TTL levels)
ECL Device Families:
MEC I 8nS*
MEC II 2nS*
MEC III (16XX) 1nS* .......* = Rise & Fall Times
101xx 100 series 10K ECL, 3.5nS*
102xx 200 series 10K ECL, 2.5nS*
108xx 800 series 10K ECL, voltage compensated, 3.5nS*
10Hxxx 10K - High speed, voltage compensated, 1.8nS*
10Exxx 10K - ECLinPS, voltage compensated, 800pS*
100xxx 100K, temperature compensated
100Hxxx 100K - High speed, temperature compensated
100Exxx 100K - ECLinPS, temp, voltage comp., 800pS*