74LS193 DIP 4-Bit Synchronous Binary Up/Down Counter
The 74LS193 is a high speed TTL integrated circuit that functions as a synchronous, reversible 4-bit binary counter. This device features a dual-clock architecture with independent inputs for incrementing and decrementing. This design allows the counter to change state based on which clock line receives a pulse, significantly simplifying the control logic for bidirectional systems. The outputs transition synchronously with the low-to-high clock edge, ensuring high-speed operation without the timing errors associated with ripple counters.
This IC is fully presettable, allowing any 4-bit binary value to be loaded through the parallel data inputs when the load terminal is pulled low. It also includes an asynchronous master reset (clear) that immediately sets all outputs to zero, regardless of the clock signals. With dedicated carry and borrow outputs, the 74LS193 is easily cascadable for multi-bit counting, making it a staple for digital volume controls, frequency synthesizers, and position tracking logic.
KEY FEATURES
- Dual clock inputs for simplified Up/Down counting control
- Fully synchronous operation for stable, high-speed performance
- Asynchronous master clear for immediate register reset
- Presettable parallel inputs for flexible starting values
- Separate Carry and Borrow outputs for seamless cascading
- Standard 16 pin dual in line package
SPECIFICATIONS
- Supply Voltage 4.75V to 5.25V
- Operating Temperature 0 to 70 Celsius
- Logic Type TTL Low Power Schottky
- Maximum Clock Frequency 25MHz
- Typical Power Dissipation 95mW
- High Level Output Current -0.4mA
- Low Level Output Current 8mA
INTERFACES
- CPU Clock Up input positive edge triggered
- CPD Clock Down input positive edge triggered
- CLR Master reset input active high
- LOAD Parallel load input active low
- A B C D Parallel data inputs
- QA QB QC QD Binary counter outputs
- CARRY Carry output active low
- BORROW Borrow output active low
- VCC Positive supply voltage
- GND Ground reference
