MC74HC74A Dual D Flip-Flop with Set and Reset HighPerformance SiliconGate CMOS The MC74HC74A is identical in pinout to the LS74. The device MC74HC74A PIN ASSIGNMENT LOGIC DIAGRAM 1 RESET 1 1 14 V RESET 1 CC DATA 1 2 13 RESET 2 5 2 DATA 1 Q1 CLOCK 1 3 12 DATA 2 6 3 Q1 CLOCK 1 SET 1 4 11 CLOCK 2 4 Q1 5 10 SET 2 SET 1 Q1 6 9 Q2 13 RESET 2 GND 7 8 Q2 9 12 DATA 2 Q2 FUNCTION TABLE 8 11 CLOCK 2 Q2 Inputs Outputs 10 Set Reset Clock Data Q Q SET 2 LH X X HL PIN 14 = V CC HL X X LH PIN 7 = GND L L X X H* H* HH H H L HH L L H H H L X No Change H H H X No Change H H X No Change *Both outputs will remain high as long as Set and Reset are low, but the output states are unpredictable if Set and Reset go high simultaneously. MAXIMUM RATINGS Symbol Parameter Value Unit This device contains protection circuitry to guard against damage V DC Supply Voltage (Referenced to GND) 0.5 to + 7.0 V CC due to high static voltages or electric V DC Input Voltage (Referenced to GND) 0.5 to V + 0.5 V in CC fields. However, precautions must V DC Output Voltage (Referenced to GND) 0.5 to V + 0.5V out CC be taken to avoid applications of any I DC Input Current, per Pin 20 mA voltage higher than maximum rated in voltages to this highimpedance cir- I DC Output Current, per Pin 25 mA out cuit. For proper operation, V and in I DC Supply Current, V and GND Pins 50 mA CC CC V should be constrained to the out P mW Power Dissipation in Still Air, Plastic DIP 750 D range GND (V or V ) V . in out CC SOIC Package 500 Unused inputs must always be TSSOP Package 450 tied to an appropriate logic voltage level (e.g., either GND or V ). CC T Storage Temperature 65 to + 150 C stg Unused outputs must be left open. T C Lead Temperature, 1 mm from Case for 10 Seconds L (Plastic DIP, SOIC or TSSOP Package) 260 300 Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. Derating Plastic DIP: 10 mW/ C from 65 to 125 C SOIC Package: 7 mW/ C from 65 to 125 C TSSOP Package: 6.1 mW/ C from 65 to 125 C RECOMMENDED OPERATING CONDITIONS Symbol Parameter Min Max Unit V DC Supply Voltage (Referenced to GND) 2.0 6.0 V CC V , V DC Input Voltage, Output Voltage (Referenced to GND) 0 V V in out CC T Operating Temperature, All Package Types 55 + 125 C A t , t Input Rise and Fall Time V = 2.0 V 0 1000 ns r f CC (Figures 1, 2, 3) V = 3.0 V 0 600 CC V = 4.5 V 0 500 CC V = 6.0 V 0 400 CC