TECHNICAL DATA IN74AC138 1-of-8 Decoder/Demultiplexer High-Speed Silicon-Gate CMOS The IN74AC138 is identical in pinout to the LS/ALS138, HC/HCT138. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALS outputs. The IN74AC138 decodes a three-bit Address to one-of-eight activelow outputs. This device features three Chip Select inputs, two active-low and one active-high to facilitate the demultiplexing, cascading, and chipselecting functions. The demultiplexing function is accomplished by using the Address inputs to select the desired device output; one of the Chip Selects is used as a data input while the other Chip Selects are held in their active states. • Outputs Directly Interface to CMOS, NMOS, and TTL • Operating Voltage Range: 2.0 to 6.0 V • Low Input Current: 1.0 μA; 0.1 μA @ 25°C • High Noise Immunity Characteristic of CMOS Devices • Outputs Source/Sink 24 mA ORDERING INFORMATION IN74AC138N Plastic IN74AC138D SOIC TA = -40° to 85° C for all packages PIN ASSIGNMENT LOGIC DIAGRAM FUNCTION TABLE Inputs PIN 16 =VCC PIN 8 = GND Outputs CS1 CS2 CS3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 X X H X H X L X X X X X X X X X X X H H H H H H H H H H H H H H H H H H H H H H H H H H H H L L L L L L L L L L L L L L H H L H L H L H H H H L H H H H L H H H H L H H H H H H H H H H H H H H H H H H H H L L L L L L L L H H H H L L H H L H L H H H H H H H H H H H H H H H H H L H H H H L H H H H L H H H H L H = high level (steady state) L = low level (steady state) X = don’t care Rev. 00 IN74AC138 MAXIMUM RATINGS* Symbol Parameter Value Unit -0.5 to +7.0 V VCC DC Supply Voltage (Referenced to GND) VIN DC Input Voltage (Referenced to GND) -0.5 to VCC +0.5 V DC Output Voltage (Referenced to GND) -0.5 to VCC +0.5 V DC Input Current, per Pin ±20 mA IOUT DC Output Sink/Source Current, per Pin ±50 mA ICC DC Supply Current, VCC and GND Pins ±50 mA PD Power Dissipation in Still Air, Plastic DIP+ SOIC Package+ 750 500 mW -65 to +150 °C 260 °C VOUT IIN Tstg TL Storage Temperature Lead Temperature, 1 mm from Case for 10 Seconds (Plastic DIP or SOIC Package) * Maximum Ratings are those values beyond which damage to the device may occur. Functional operation should be restricted to the Recommended Operating Conditions. +Derating - Plastic DIP: - 10 mW/°C from 65° to 125°C SOIC Package: : - 7 mW/°C from 65° to 125°C RECOMMENDED OPERATING CONDITIONS Symbol VCC VIN, VOUT DC Supply Voltage (Referenced to GND) DC Input Voltage, Output Voltage (Referenced to GND) TJ Junction Temperature (PDIP) TA Operating Temperature, All Package Types IOH Output Current - High IOL Output Current - Low tr, tf * Parameter Input Rise and Fall Time (except Schmitt Inputs) * Min Max Unit 2.0 6.0 V 0 VCC V 140 °C +85 °C -24 mA 24 mA 150 40 25 ns/V -40 VCC =3.0 V VCC =4.5 V VCC =5.5 V 0 0 0 VIN from 30% to 70% VCC This device contains protection circuitry to guard against damage due to high static voltages or electric fields. However, precautions must be taken to avoid applications of any voltage higher than maximum rated voltages to this high-impedance circuit. For proper operation, VIN and VOUT should be constrained to the range GND≤(VIN or VOUT)≤VCC. Unused inputs must always be tied to an appropriate logic voltage level (e.g., either GND or VCC). Unused outputs must be left open. Rev. 00 IN74AC138 DC ELECTRICAL CHARACTERISTICS (Voltages Referenced to GND) VCC Symbol Parameter Test Conditions Guaranteed Limits V 25 °C -40°C to 85°C Unit VIH Minimum HighLevel Input Voltage VOUT=0.1 V or VCC-0.1 V 3.0 4.5 5.5 2.1 3.15 3.85 2.1 3.15 3.85 V VIL Maximum Low Level Input Voltage VOUT=0.1 V or VCC-0.1 V 3.0 4.5 5.5 0.9 1.35 1.65 0.9 1.35 1.65 V VOH Minimum HighLevel Output Voltage IOUT ≤ -50 μA 3.0 4.5 5.5 2.9 4.4 5.4 2.9 4.4 5.4 V 3.0 4.5 5.5 2.56 3.86 4.86 2.46 3.76 4.76 3.0 4.5 5.5 0.1 0.1 0.1 0.1 0.1 0.1 VIN= VIH or VIL IOL=12 mA IOL=24 mA IOL=24 mA 3.0 4.5 5.5 0.36 0.36 0.36 0.44 0.44 0.44 Maximum Input Leakage Current VIN=VCC or GND 5.5 ±0.1 ±1.0 μA IOLD +Minimum Dynamic Output Current VOLD=1.65 V Max 5.5 75 mA IOHD +Minimum Dynamic Output Current VOHD=3.85 V Min 5.5 -75 mA ICC Maximum Quiescent Supply Current (per Package) VIN=VCC or GND 5.5 80 μA * VIN=VIH or VIL IOH=-12 mA IOH=-24 mA IOH=-24 mA VOL Maximum LowLevel Output Voltage IOUT ≤ 50 μA V * IIN 8.0 * All outputs loaded; thresholds on input associated with output under test. +Maximum test duration 2.0 ms, one output loaded at a time. Note: IIN and ICC @ 3.0 V are guaranteed to be less than or equal to the respective limit @ 5.5 V VCC Rev. 00 IN74AC138 AC ELECTRICAL CHARACTERISTICS (CL=50pF,Input tr=tf=3.0 ns) VCC* Symbol Parameter Guaranteed Limits 25 °C V Unit -40°C to 85°C Min Max Min Max tPLH Propagation Delay, Input A to Output Y (Figure 1) 3.3 5.0 1.5 1.5 13.0 9.5 1.5 1.5 15.0 10.5 ns tPHL Propagation Delay, Input A to Output Y (Figure 1) 3.3 5.0 1.5 1.5 12.5 9.0 1.5 1.5 14.0 10.5 ns tPLH Propagation Delay, CS2 or CS3 to Output Y (Figure 3) 3.3 5.0 1.5 1.5 15.0 11.0 1.5 1.5 16.0 12.0 ns tPHL Propagation Delay, CS2 or CS3 to Output Y (Figure 3) 3.3 5.0 1.5 1.5 13.5 9.5 1.5 1.5 15.0 10.5 ns tPLH Propagation Delay, CS1 to Output Y (Figure 2) 3.3 5.0 1.5 1.5 15.5 11.0 1.5 1.5 16.5 12.5 ns tPHL Propagation Delay, CS1 to Output Y (Figure 2) 3.3 5.0 1.5 1.5 13.0 8.0 1.5 1.0 14.0 9.5 ns CIN Maximum Input Capacitance 5.0 4.5 4.5 pF Typical @25°C,VCC=5.0 V CPD Power Dissipation Capacitance 60 pF Voltage Range 3.3 V is 3.3 V ±0.3 V Voltage Range 5.0 V is 5.0 V ±0.5 V * Figure 1. Switching Waveforms Figure 2. Switching Waveforms Figure 3. Switching Waveforms Rev. 00 IN74AC138 EXPANDED LOGIC DIAGRAM Rev. 00 IN74AC138 N SUFFIX PLASTIC DIP (MS - 001BB) A Dimension, mm 9 16 Symbol MIN MAX A 18.67 19.69 B 6.1 7.11 B 1 8 5.33 C F L C D 0.36 0.56 F 1.14 1.78 G 2.54 H 7.62 -T- SEATING PLANE N G K M H D J 0.25 (0.010) M T NOTES: 1. Dimensions “A”, “B” do not include mold flash or protrusions. Maximum mold flash or protrusions 0.25 mm (0.010) per side. J 0° 10° K 2.92 3.81 L 7.62 8.26 M 0.2 0.36 N 0.38 D SUFFIX SOIC (MS - 012AC) Dimension, mm A 16 9 H B 1 G P 8 R x 45 C -TK D SEATING PLANE J 0.25 (0.010) M T C M NOTES: 1. Dimensions A and B do not include mold flash or protrusion. 2. Maximum mold flash or protrusion 0.15 mm (0.006) per side for A; for B ‑ 0.25 mm (0.010) per side. F M Symbol MIN MAX A 9.8 10 B 3.8 4 C 1.35 1.75 D 0.33 0.51 F 0.4 1.27 G 1.27 H 5.72 J 0° 8° K 0.1 0.25 M 0.19 0.25 P 5.8 6.2 R 0.25 0.5 Rev. 00