CD74ACT163 - 4-Bit Sync Binary Counter 5V | Texas Instruments
Référence : CD74ACT163 ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $0.85 | $0,85 |
| 10 | $0.72 | $7,20 |
| 100 | $0.55 | $55,00 |
| 500 | $0.44 | $220,00 |
| 1 000 | $0.36 | $360,00 |
CD74ACT163 Présentation
A synchronous binary counter is a sequential logic IC in which all flip-flops are clocked simultaneously by a common clock edge, so all output bits change in coincidence rather than rippling stage to stage. Within the logic IC hierarchy (counter -> sequential logic IC -> digital IC), synchronous counters eliminate the cumulative propagation delays of ripple (asynchronous) counters, enabling reliable high-speed counting and glitch-free decoded outputs.
Key features include synchronous counting, synchronous parallel load via the active-low LOAD input for programmable counting, and synchronous reset (CLR) that clears all outputs on the next clock edge, eliminating the decoding spikes inherent in asynchronous clearing. The count-enable inputs (ENP, ENT) permit cascading and gated counting without external gating logic, and the RCO terminal supports direct n-bit cascading.
The ACT technology combines CMOS low static power with TTL input thresholds at 5V operation, making the device directly interchangeable in TTL 74163 sockets. Positive-edge clocking and fully synchronous preset, count, and clear functions simplify timing analysis in multi-stage counter chains.
Typical applications include frequency division, digital timers, event counting, address generation, industrial sequencing, and cascaded n-bit counters built by wiring RCO of one stage to ENT of the next.
Design consideration: because reset and load are synchronous, hold CLR or LOAD low for at least one full clock period; for asynchronous-reset designs use the related CD74ACT161 instead. Decouple the 5V rail with 0.1uF close to the VCC pin.
This page synthesizes distributor data, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Alternatives de remplacement direct pour CD74ACT163 — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
CD74ACT163M
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
CD74ACT163M96
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
SN74ACT163D
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
CD74ACT163 Valeurs maximales et caractéristiques électriques
| Logic Function | 4-bit synchronous presettable binary counter with synchronous reset |
| Logic Family | ACT (Advanced CMOS, TTL-compatible inputs) |
| Tension d'alimentation | 5 V |
| Number of Elements | 1 |
| Number of Bits | 4 |
| Counting Mode | Synchronous, positive-edge triggered |
| Reset Type | Synchronous (CLR) |
| Parallel Load | Synchronous (LOAD, active-low) |
| Carry Look-Ahead | Internal, for fast counting |
| Cascading Output | RCO ripple carry output for n-bit cascading |
| Input Compatibility | TTL-voltage compatible |
| Température de fonctionnement | -40C to +85C (CD74ACT163M grade) |
| Boîtier | SOIC-16 (16-pin small outline) |
| Type de montage | Surface Mount |
Configuration des broches de CD74ACT163
| Broche 1 | CLR — Synchronous clear, active-low - resets all outputs on next clock edge |
| Broche 2 | CLK — Clock input, positive-edge triggered |
| Broche 3 | A — Data input A (parallel load, QA) |
| Broche 4 | B — Data input B (parallel load, QB) |
| Broche 5 | C — Data input C (parallel load, QC) |
| Broche 6 | D — Data input D (parallel load, QD) |
| Broche 7 | ENP — Count enable parallel input |
| Broche 8 | GND — Ground |
| Broche 9 | LOAD — Synchronous parallel load control, active-low |
| Broche 10 | ENT — Count enable trickle input (gates counting and RCO) |
| Broche 11 | QD — Counter output D (MSB) |
| Broche 12 | QC — Counter output C |
| Broche 13 | QB — Counter output B |
| Broche 14 | QA — Counter output A (LSB) |
| Broche 15 | RCO — Ripple carry output for n-bit cascading |
| Broche 16 | VCC — Power supply, 5 V nominal |
Applications typiques
CD74ACT163 convient pour 6 applications: Frequency Division, Digital Timers and Event Counting, Cascaded n-Bit Counters, Address Generation and Sequencing, Industrial Control Sequencing, Test and Measurement Counters.
Frequency Division
The CD74ACT163 divides an input clock frequency by an arbitrary integer from 2 to 16 using its synchronous LOAD and carry look-ahead architecture. Because all flip-flops clock simultaneously, the divided output has no ripple-induced glitches, making it safe to feed decoded division outputs into clock trees or PLL reference inputs. In a typical divide-by-N configuration, the Q outputs feed a comparator that asserts LOAD to reload the terminal count, and the internal carry look-ahead keeps the loop timing deterministic at high input frequencies. The 5V ACT family also provides TTL-level clock compatibility with legacy oscillator modules. Place 0.1uF decoupling at VCC to keep clock edges clean.
Recommandé
Digital Timers and Event Counting
In timer and event-counting roles, the CD74ACT163 accumulates pulses from a sensor or clock source and presents a latched 4-bit count on QA-QD. The synchronous reset allows the host controller to clear the count on a clock boundary, guaranteeing no partial-count artifacts, while ENP/ENT enable gated counting so external gates can start and stop accumulation without extra gating logic. The internal carry look-ahead keeps counts accurate at high event rates where ripple counters would smear transitions. Multiple stages cascade through RCO-to-ENT wiring to extend the count range to 8, 12, or 16 bits. The 5V supply suits industrial panel environments with legacy TTL signal levels.
Recommandé
Cascaded n-Bit Counters
The CD74ACT163 is purpose-built for cascading: wiring each stage's RCO to the next stage's ENT creates fully synchronous 8-, 12-, or 16-bit counters with a common clock, so all bits change on the same edge and decoded outputs are glitch-free. The internal carry look-ahead removes the need for external ripple delay compensation, and ENP/ENT gating allows conditional counting across the whole chain. This is the standard architecture for high-resolution position counters, batch counters, and time-of-day clocks in PLC-style designs. At 5V with TTL-compatible inputs, the chain interfaces directly with legacy processor buses. Keep the common clock short and star-routed to limit skew between stages.
Recommandé
Address Generation and Sequencing
Using its synchronous parallel load inputs A-D and LOAD control, the CD74ACT163 generates programmable address or state sequences: load any starting value, count up synchronously, and reload to create circular address generators for memory scanning, lookup-table stepping, or display multiplexing. The synchronous reset gives a clean return to zero aligned to the clock, and carry look-ahead supports fast stepping in scan chains. Because outputs transition coincidentally, address decoders driving memory or peripheral selects see no transient spurious addresses, a common failure mode with ripple counters. The 5V ACT I/O matches legacy microprocessor and SRAM control signal levels directly, minimizing interface glue.
Recommandé
Industrial Control Sequencing
On factory automation panels, the CD74ACT163 provides deterministic step sequencing for machinery state machines, stepper indexing, and batch process control. The 5V supply and TTL-compatible inputs integrate cleanly with 24V-referenced I/O once level-shifted through optocouplers or transistor buffers, and the synchronous LOAD/CLR functions let a PLC reload or zero the sequence on the next clock edge, avoiding mid-step partial states. The internal carry look-ahead supports rapid step rates for fast pick-and-place cycles, and RCO cascading extends sequences beyond 16 states. Its surface-mount SOIC-16 footprint suits both new SMD boards and retrofit adapters. pair with watchdog logic to reset stuck sequences.
Recommandé
Test and Measurement Counters
Bench instruments and embedded diagnostic modules use the CD74ACT163 as a prescaler or event tally in frequency meters, pulse counters, and pattern generators. The positive-edge clock with simultaneous flip-flop switching yields clean count boundaries essential for measurement repeatability, and the synchronous parallel load supports arbitrary modulo-N presets from firmware. TTL-compatible inputs accept signals from standard probe and signal-generator levels at 5V, while the RCO output feeds higher-order counter stages for extended range. Because the device is fully synchronous, measurement uncertainty from internal propagation skew is eliminated, improving count accuracy at high input frequencies. Use short ground-return paths for the clock input.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour CD74ACT163 — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | CD74ACT163M | CD74ACT163M96 | SN74ACT163D |
|---|---|---|---|---|
| Package | SOIC-16 | SOIC-16 - same | SOIC-16 - same | SOIC-16 - same |
| Brand | Texas Instruments | Texas Instruments (Rochester Electronics supply) | Texas Instruments | Texas Instruments |
| Logic Function | 4-bit sync presettable binary counter, sync reset | 4-bit sync presettable binary counter, sync reset | 4-bit sync presettable binary counter, sync reset | 4-bit sync presettable binary counter, sync reset |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V |
| Reset Type | Synchronous | Synchronous | Synchronous | Synchronous |
| Input Compatibility | TTL-voltage compatible | TTL-voltage compatible | TTL-voltage compatible | TTL-voltage compatible |
| Carry Look-Ahead / RCO | Yes (internal look-ahead, RCO for cascading) | Yes | Yes | Yes |
Principaux différenciateurs
- Synchronous reset eliminates decoding glitches (vs CD74ACT161 (asynchronous reset version))
- Internal carry look-ahead for high-speed counting (vs Simpler ripple counters (e.g., CD4029-class parts))
- Continued availability via second-source channel (vs CD74ACT163M (Harris die via Rochester Electronics))
Notes de conception
CLR and LOAD on the CD74ACT163 are synchronous: they take effect only on the next rising clock edge, not immediately. Hold the control signal low for at least one full clock period to guarantee the operation executes. Designs ported from asynchronous-clear counters (e.g., CD74ACT161 or 74161) will behave differently - a brief CLR pulse that would asynchronously clear a 161 will do nothing on a 163 if it does not overlap a clock edge. This is the single most common migration error.
Decouple the 5V rail with a 0.1uF ceramic capacitor placed within a few millimeters of pin 16 (VCC) and pin 8 (GND). ACT-family devices drive fast edges into TTL-level loads, and simultaneous switching of four outputs can inject supply noise that falsely clocks the counter. Add a bulk 4.7uF-10uF capacitor per counter cluster on boards with multiple cascaded stages. Avoid long shared ground returns between the clock source and the counter ground pin.
When cascading multiple CD74ACT163 stages, tie all CLK pins to a single clock net routed as a short star or daisy chain with matched lengths to minimize inter-stage clock skew; skew larger than a few nanoseconds can break the coincident-output property that makes the design glitch-free. Route RCO-to-ENT connections away from the clock net to avoid coupling. Keep decoded-output traces short since fast ACT edges can radiate.
Informations de conformité
Compliance status varies by ordering suffix; verify on the TI CD74ACT163 product page (Ordering and quality section) for the exact suffix ordered.
