TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic
Low-Voltage 3-to-8 Line Decoder with 5-V Tolerant Inputs and Outputs
The TC74LCX138 is a high-performance CMOS 3-to-8 decoder.
Designed for use in 3.3-V systems, it achieves high-speed operation
while maintaining the CMOS low-power dissipation.
The device is designed for low-voltage (3.3 V) VCC applications, but it
could be used to interface to 5-V supply environment for inputs.
When the device is enabled, 3 binary select inputs (A, B and C)
determine which one of the outputs ( Y0 - Y7 ) will go low.
When enable input G1 is held low or either G2A or G2B is held
high, decoding function is inhibited and all outputs go high.
G1, G2A , and G2B inputs are provided to ease cascade connection
and for use as an address decoder for memory systems.
All inputs are equipped with protection circuits against static
• Low-voltage operation: VCC = 1.65 to 3.6 V
• High-speed operation: tpd = 6.0 ns (max) (VCC = 3.0 to 3.6 V)
• Ouput current: |IOH|/IOL = 24 mA (min) (VCC = 3.0 V)
• Latch-up performance: ＞±500 mA
• Available in JEITA SOP, VSSOP (US)
• Power-down protection provided on all inputs and outputs
• Pin and function compatible with the 74 series
(74AC/VHC/HC/F/ALS/LS etc.) 138 type
: 0.18 g ( typ.)
: 0.02 g ( typ.)
Note: The Electrical Characteristics of VCC = 1.8 ± 0.15 V is only applicable for products which manufactured
from January 2009 onward.
Toshiba Electronic Devices & Storage Corporation
Start of commercial production