1. General description
The 74LV138 decodes three binary weighted address inputs (A0, A1 and A2) to eight mutually
exclusive outputs (Y0 to Y7). The 74LVC138A features three enable inputs (Y1, Y2 and E3). Every
output will be HIGH unless Y1 and Y2 are LOW and E3 is HIGH. This multiple enable function
allows easy parallel expansion of the 74LV138 to a 1-of-32 (5 to 32 lines) decoder with just four
74LV138 ICs and one inverter. The 74LV138 can be used as an eight output demultiplexer by using
one of the active LOW enable inputs as the data input and the remaining enable inputs as strobes.
Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to
voltages in excess VCC.
2. Features and benefits
• Wide supply voltage range from 1.0 to 5.5 V
• Optimized for low voltage applications: 1.0 V to 3.6 V
• CMOS low power dissipation
• Direct interface with TTL levels
• Typical output ground bounce < 0.8 V at VCC = 3.3 V and Tamb = 25 °C
• Typical HIGH-level output voltage (VOH) undershoot: > 2 V at VCC = 3.3 V and Tamb = 25 °C
• Demultiplexing capability
• Multiple input enable for easy expansion
• Ideal for memory chip select decoding
• Active LOW mutually exclusive outputs
• Latch-up performance exceeds 100 mA per JESD 78 Class II Level B
• Complies with JEDEC standards
• JESD8-7 (1.65 V to 1.95 V)
• JESD8-5 (2.3 V to 2.7 V)
• JESD8C (2.7 V to 3.6 V)
• JESD36 (4.5 V to 5.5 V)
• ESD protection:
• HBM JESD22-A114E exceeds 2000 V
• MM JESD22-A115-A exceeds 200 V
• Multiple package options
• Specified from -40 °C to +85 °C and from -40 °C to +125 °C