SL74HC138 SLS | Alldatasheet

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Technical content

1-of-8 Decoder/Demultiplexer High-Performance Silicon-Gate CMOS The SL74HC138 is identical in pinout to the LS/ALS138. The device inputs ar e compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs. The SL74HC138 decodes a three-bit Address to one -of-eight active - low outputs. This device features three Chip Select inputs, two active - low and one active-high to facilitate the demultiplexing, cascading, and chip-selecting 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 ot her 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
  • High Noise Immunity Characteristic of CMOS Devices

ORDERING INFORMATION

TA = -55° to 125° C for all packages PIN ASSIGNMENT FUNCTION TABLE Inputs 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 L L H L L H L L H L L L L L L L H L H L L H H L H H H H H H H H L H H H H H H H H L H H H H H H H H L H H H H H L L H L L H L L H L L H L L H L H H H L H H H H H H H L H H H H H H H H L H H H H H H H H L H H H H H H H H L H = high level (steady state) L = low level (steady state) X = don’t care LOGIC DIAGRAM PIN 16 =VCC PIN 8 = GND

MAXIMUM RATINGS* Symbol Parameter Value Unit VCC DC Supply Voltage (Referenced to GND) -0.5 to +7.0 V VIN DC Input Voltage (Referenced to GND) -1.5 to VCC +1.5 V VOUT DC Output Voltage (Referenced to GND) -0.5 to VCC +0.5 V IIN DC Input Current, per Pin ±20 mA IOUT DC Output Current, per Pin ±25 mA ICC DC Supply Current, VCC and GND Pins ±50 mA PD Power Dissipation in Still Air, Plastic DIP+ 750 500 mW Tstg Storage Temperature -65 to +150 °C TL Lead Temperature, 1 mm from Case for 10 Seconds (Plastic DIP or SOIC Package) 260 °C *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 RECOMMENDED OPERATING CONDITIONS Symbol Parameter Min Max Unit VCC DC Supply Voltage (Referenced to GND) 2.0 6.0 V VIN, VOUT DC Input Voltage, Output Voltage (Referenced to GND) 0 VCC V TA Operating Temperature, All Package Type s -55 +125 °C tr, tf Input Rise and Fall Time (Figure 2) VCC =2.0 V VCC =4.5 V VCC =6.0 V 1000 500 400 ns This device contains protection circuitry to guard against damage due to high static voltages or electric fields. However, precautions m ust be taken to avoid applications of any voltage higher than maximum rated voltages to this high -impedance circuit. For proper operation, V IN and VOUT should be constrained to the range GND≤(VIN or VOUT)≤VCC. Unused inputs must always be tied to an approp riate logic voltage level (e.g., either GND or V CC). Unused outputs must be left open.

DC ELECTRICAL CHARACTERISTICS(Voltages Referenced to GND) VCC Guaranteed Limit Symbol Parameter Test Conditions V 25 °C to -55°C ≤85 ≤125 Unit VIH Minimum High-Level Input Voltage VOUT=0.1 V or VCC-0.1 V IOUT≤ 20 µA 2.0 4.5 6.0 1.5 3.15 4.2 1.5 3.15 4.2 1.5 3.15 4.2 V VIL Maximum Low -Level Input Voltage VOUT=0.1 V or VCC-0.1 V IOUT ≤ 20 µA 2.0 4.5 6.0 0.5 1.35 1.8 0.5 1.35 1.8 0.5 1.35 1.8 V VOH Minimum High-Level Output Voltage VIN=VIH or VIL IOUT ≤ 20 µA 2.0 4.5 6.0 1.9 4.4 5.9 1.9 4.4 5.9 1.9 4.4 5.9 V VIN=VIH or VIL IOUT ≤ 4.0 mA IOUT ≤ 5.2 mA 4.5 6.0 3.98 5.48 3.84 5.34 3.7 5.2 VOL Maximum Low-Level Output Voltage VIN=VIH or VIL IOUT ≤ 20 µA 2.0 4.5 6.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 V VIN=VIH or VIL IOUT ≤ 4.0 mA IOUT ≤ 5.2 mA 4.5 6.0 0.26 0.26 0.33 0.33 0.4 0.4 IIN Maximum Input Leakage Current VIN=VCC or GND 6.0 ±0.1 ±1.0 ±1.0 µA ICC Maximum Quiescent Supply Current (per Package) VIN=VCC or GND IOUT=0µA 6.0 4.0 40 160 µA

Figure 1. Switching Waveforms Figure 2. Switching Waveforms

Figure 3. Switching Waveforms Figure 4. Test Circuit