The DM5490AJ is a BCD (Binary Coded Decimal) Decade Counter manufactured by National Semiconductor (now Texas Instruments). It's a member of the 54/74 series of TTL (Transistor-Transistor Logic) integrated circuits, designed for use in military and high-reliability applications due to its extended temperature range. The '54' prefix indicates operation over the military temperature range (-55°C to +125°C). The categorization as END-OF-LIFE signifies that the component is no longer actively manufactured and finding suitable replacements is necessary for new designs.

Applications

• Frequency Dividers
• Digital Clocks
• Event Counters
• Numerical Displays
• Instrumentation

Features

• BCD Decade Counter
• TTL Logic Family
• Military Temperature Range Operation
• Asynchronous Operation
• Reset-to-Zero Capability

Benefits

• Precise Counting: Provides accurate counting in BCD format for numerical applications.
• Reliable Operation: Designed for operation over a wide temperature range and in harsh environments.
• Easy Implementation: Easy to integrate into digital circuits due to standard TTL voltage levels.
• Versatile Functionality: Can be used in a variety of counting and frequency division applications.
• Simplified Display Interface: BCD output simplifies interfacing with numerical displays.

Additional Details

The DM5490AJ is typically housed in a ceramic DIP (Dual In-line Package) to withstand the extreme operating temperatures. The device requires a 5V power supply for proper operation. The BCD output represents the count from 0 to 9. The reset input allows for synchronous resetting of the counter to zero. The clock input triggers the counting sequence. Due to the END-OF-LIFE status, consider using readily available CMOS decade counters like the CD4017 or newer TTL equivalents. When substituting, verify the pinout and logic levels for compatibility. Refer to the Texas Instruments (TI) datasheet for detailed specifications and application circuits. Proper decoupling capacitors should be used to ensure stable operation.