Limited Stock

Texas Instruments SN74LS193N Vintage 1977 TTL 4-Bit Up Down Binary Counter DIP-16 Arcade Logic IC

ICs / Integrated Circuits • SKU RFB00529

$4.95

Vintage Texas Instruments SN74LS193N low-power Schottky TTL synchronous 4-bit binary up/down counter integrated circuit in a 16-pin DIP package. This original Texas Instruments example carries date code 7727, consistent with production during the 27th week of 1977, and is marked as El Salvador production.

The SN74LS193N is a four-bit synchronous reversible binary counter designed to count upward or downward using separate count-up and count-down clock inputs. It also provides asynchronous parallel loading, an independent clear input, four binary outputs, and carry and borrow outputs that allow multiple counters to be cascaded when a wider counting range is required.

Designed for classic 5V TTL circuitry, the SN74LS193N was widely applicable to digital counters, computers, computer peripherals, industrial control systems, instrumentation, communications equipment, test equipment, timing systems, sequence-control circuits, position counters, display systems, and other digital electronic equipment.

The exact Texas Instruments SN74LS193N is NOT obsolete. Texas Instruments continues to classify the SN74LS193N 16-pin PDIP device as ACTIVE production. This particular component is desirable as original NOS 1977 Texas Instruments production and as period-era restoration stock rather than because the underlying part number has been discontinued.

HISTORICAL BACKGROUND:

The 74LS193 belongs to the low-power Schottky generation of the classic 7400-series TTL family. During the 1970s and early 1980s, individual counters such as the 74LS193 performed functions that would later be absorbed into microprocessors, custom logic devices, and programmable controllers.

Its ability to count both upward and downward made it especially useful in equipment that needed to track position, addresses, timing events, numerical values, or changing control states. Separate clock inputs simplified bidirectional counting, while parallel loading allowed a predetermined binary value to be entered directly into the counter.

The 74LS193 also has strong documented vintage arcade history. Atari Asteroids uses three 74LS193 devices at PCB locations F5, H5, and J5. Atari Asteroids Deluxe likewise uses three 74LS193 devices at locations F4, H4, and J4. These counters form part of the extensive discrete TTL logic architecture used by Atari's early vector-game hardware.

That documented usage makes an original 1977 Texas Instruments SN74LS193N useful repair stock for vintage arcade technicians restoring original Atari boards, particularly where a period-manufacturer component is desirable.

The SN74LS193N was not designed exclusively for arcade equipment. It was a general-purpose digital logic component with applications throughout computers, industrial control systems, instrumentation, communications equipment, test gear, and other TTL-era electronics.