SN74LS92N - Divide-by-12 4-Bit Counter | Texas Instruments
MPN: SN74LS92N ✓ ActiveSN74LS92N Overview
A ripple counter is a digital counter type within the logic IC hierarchy. Unlike a synchronous counter, its internal stages do not all change on the same clock edge; ripple transitions propagate through successive flip-flops. This architecture is useful when the required count sequence is simple, the clock frequency is moderate, and the next logic stage does not require all counter outputs to switch simultaneously. The SN74LS92N belongs to the SN74LS low-power Schottky TTL family of counters and dividers.
The principal functional attributes are its 4-bit counter organization, single divide-by-12 counting element, positive-edge triggering, and 14-pin PDIP package. The verified distributor listing describes the SN74LS92N as a counter and divider IC with one element, four bits, and positive-edge operation. The manufacturer datasheet describes the internal implementation as four master-slave flip-flops plus additional gating. These details distinguish it from decade counters, binary divide-by-8 counters, and general-purpose multi-section counter ICs.
Because it uses ripple-style internal propagation, the design should account for the timing relationship among the counter outputs rather than assuming synchronous counter behavior. External logic should be connected to the appropriate decoded count states, and unused inputs must be held at defined logic levels. Power and logic-level details should be confirmed in the current manufacturer datasheet before it is used in a new high-speed or industrial design.
Typical applications include divide-by-12 clock generation in older digital systems, pulse and event counting, modulo-12 sequencing, industrial timing modules, and legacy control systems that require a standard TTL counter function. The SN74LS92N is especially relevant for maintaining 74LS-series logic rather than designing a new synchronous counter around a modern programmable device.
The primary design trade-off is flexibility versus complexity. A dedicated counter is simpler than a programmable MCU for a fixed modulo-12 function, but its operating speed, logic thresholds, power dissipation, and propagation behavior remain those of the original TTL family. Confirm those characteristics against the manufacturer documentation before replacing a modern high-speed counter in timing-critical circuitry.
This page consolidates verified manufacturer and distributor information, package details, practical application guidance, and same-footprint counter alternatives to support component identification, sourcing, and legacy-design maintenance.
Drop-in alternatives for SN74LS92N — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with SN74LS92N (same form factor and footprint) — differing in Counter Type, Counting Direction, Logic Family, Mounting Type, Package.
SN74LS92D
✅ Drop-In ⚠️ Specs UnverifiedContact for price
View Datasheet →SN74LS92N
✅ Drop-InContact for price
View Datasheet →DM74LS92N
✅ Drop-In📋 Reference alternative (not in catalog)
74LS92N
✅ Drop-In📋 Reference alternative (not in catalog)
TC74LS92AP
✅ Drop-In📋 Reference alternative (not in catalog)
SN74LS92N Maximum Ratings & Electrical Characteristics
| Counter Type | 4-bit ripple-type counter |
| Overall Divide Ratio | 12:1 |
| Counter Elements | 1 element |
| Counter Width | 4 bit |
| Counting Direction | Up |
| Clock Edge | Positive edge |
| Internal Flip-Flops | 4 master-slave flip-flops |
| Logic Family | SN74LS low-power Schottky TTL |
| Package | 14-pin PDIP |
| Mounting Type | Through-hole |
SN74LS92N 14-pin pdip Pin Configuration Guide
Pin configuration for SN74LS92N (14-pin pdip package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for SN74LS92N.
Refer to the datasheet for full pin configuration.
Typical Applications
SN74LS92N is suitable for 6 applications: Divide-by-12 Clock Generation, Industrial Pulse and Event Counting, Modulo-12 Sequencing, Legacy TTL Control-System Maintenance, Frequency Division in Test Equipment, Timing-Module and Counter Retrofit.
Divide-by-12 Clock Generation
The SN74LS92N is appropriate for generating a divided clock when the required ratio is exactly 12 and the surrounding circuit uses 74LS logic. Its verified 4-bit, positive-edge counter architecture produces one complete count cycle for every 12 input-clock pulses. The 14-pin PDIP package also makes it practical for preserving the original through-hole layout during maintenance. Designers should confirm maximum operating frequency and output transition behavior in the manufacturer datasheet, especially if the divided clock is used to trigger another sequential element. Because the internal architecture is ripple-based, downstream decoding should be designed around the relevant output propagation intervals rather than treated as a modern synchronous counter.
Recommended
Industrial Pulse and Event Counting
The SN74LS92N can count recurring input events in legacy industrial control, test, and automation modules that require a fixed modulo-12 sequence. Its single 4-bit counting element and divide-by-12 ratio are suitable for counting machine actuations, test cycles, or repeated sensor events without a programmable controller. The positive-edge trigger allows the circuit to respond at a defined clock transition when the source is suitably conditioned. Engineers should use debouncing or filtering for mechanical inputs, preserve signal amplitude and timing margins for the selected logic family, and verify supply limits and environmental requirements before deploying the part in new machinery.
Recommended
Modulo-12 Sequencing
The SN74LS92N is useful in legacy sequencing circuits that must repeat a fixed 12-state operating cycle. Its divide-by-12 counter action supplies a periodic count reference, while external decode and logic can select desired positions in the sequence. This arrangement can support relay-timing, display-multiplexing, or repetitive mechanism-control functions where a dedicated modulo counter is simpler than implementing the task in software. The designer should inspect all available count outputs and their transition relationships in the datasheet, decode only the required states, and account for ripple propagation when multiple outputs can change near a clock boundary.
Recommended
Legacy TTL Control-System Maintenance
The SN74LS92N is a strong candidate for repairing or extending an existing 74LS-series control board because it preserves the established divide-by-12 counter function in a 14-pin PDIP package. Matching the original logic family helps avoid unexpected input-threshold and output-level changes that can complicate diagnosis of a mixed TTL and CMOS retrofit. The verified product data confirms one 4-bit positive-edge counter element, while the manufacturer datasheet explains its gated master-slave implementation. Before substitution, confirm pin assignments, supply requirements, timing margins, and the lifecycle status of each candidate so that a maintenance repair does not introduce an unintended family mismatch.
Recommended
Frequency Division in Test Equipment
The SN74LS92N can divide repetitive test or stimulus pulses into a slower reference for instruments and measurement fixtures built with 74LS logic. The exact 12:1 ratio is convenient when a test sequence must occur once per twelve input cycles or when a known lower-rate marker is needed. The part's 4-bit counter width and 14-pin PDIP construction support straightforward through-hole repair work, but output drive and maximum clock frequency must match the following stage's requirements. Verify the manufacturer timing diagram, output loading, and power characteristics rather than assuming performance from a generic 74LS family description.
Recommended
Timing-Module and Counter Retrofit
The SN74LS92N is suitable for a small timing module that must provide repeatable 12-step timing without a microcontroller. Its dedicated divide-by-12 action reduces the number of external sequential components, while the positive-edge trigger provides a defined counting reference. A retrofit is most reliable when the original schematic identifies the same 14-pin arrangement and the replacement remains within the original TTL supply and input-level assumptions. Test the maximum event rate, reset behavior, and decoded transitions on hardware because ripple-type propagation can affect how closely spaced external outputs are used.
Recommended
Recommended Products Summary
Engineering reference data for SN74LS92N — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN74LS92 | SN74LS92N | DM74LS92N | 74LS92N | TC74LS92AP |
|---|---|---|---|---|---|---|
| Package | 14-pin PDIP | PDIP-14 | 14-pin PDIP | PDIP-14 | PDIP-14 | PDIP-14 |
| Brand | Texas Instruments | Texas Instruments | onsemi | onsemi | Nexperia | Toshiba |
| Counter Function | Divide-by-12 | Divide-by-12 | Divide-by-12 | Divide-by-12 | Divide-by-12 | Divide-by-12 |
| Counter Width | 4 bit | 4 bit | 4 bit | 4 bit | 4 bit | 4 bit |
| Counter Elements | 1 element | 1 element | 1 element | 1 element | 1 element | 1 element |
| Counting Direction | Up | Up | Up | Up | Up | Up |
| Clock Edge | Positive edge | Positive edge | Positive edge | Positive edge | Positive edge | Positive edge |
| Internal Architecture | 4 master-slave flip-flops with additional gating | 4 master-slave flip-flops with gating | 4 master-slave flip-flops with gating | 4 master-slave flip-flops with gating | 74LS divide-by-12 counter architecture | 74LS divide-by-12 counter architecture |
Key Differentiators
- Dedicated divide-by-12 operation (vs SN74LS93)
- Verified 4-bit positive-edge counter organization (vs SN74LS90)
- Direct 14-pin PDIP replacement format (vs 74HC-series surface-mount counter)
- Single-source logic-family continuity (vs 74LS92N)
Design Notes
Treat the SN74LS92N as a ripple counter rather than assuming simultaneous output transitions. Route counter outputs to decoding logic with attention to propagation delay, and avoid sampling adjacent count states on the same clock edge if the decoded meaning could change during the ripple interval. The manufacturer timing diagram should be used to establish safe hold and decode margins before increasing the input frequency.
For a replacement in an existing board, confirm that the 14-pin PDIP footprint, pin-1 orientation, power pin, ground pin, clear inputs, and clock connections correspond to the candidate part. Do not rely only on the generic DIP-14 outline; logic terminal assignments and clear-input behavior must match the schematic and manufacturer pin table.
Use the supply voltage and input/output thresholds specified by the manufacturer rather than assuming every device carrying the 74LS name has identical limits. Check the amount of current drawn by all connected LS-family loads and ensure the counter's output current rating is not exceeded. Decoupling should follow the application guidance in the manufacturer datasheet.
Do not substitute a CMOS 74HC-family counter solely because it also performs a divide-by-12 function. Supply-voltage range, input thresholds, output levels, timing, and pin behavior may differ. A legitimate drop-in choice should preserve the 14-pin footprint, pin assignments, logical function, and required electrical characteristics; otherwise the board may require modification or a pull-up, pull-down, or interface redesign.
Compliance Information
The supplied manufacturer and distributor excerpts do not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status. AEC-Q100 is treated as not applicable because the SN74LS92N is a general-purpose logic IC rather than an automotive-qualified device.
