CD4520BE - Dual 4-Bit Binary Up-Counter | Texas Instruments
Артикул: CD4520BE ✓ АктивенCD4520BE Обзор
A binary counter is a sequential digital-logic component that stores a multi-bit numerical value and advances that value by one on each active clock event. The CD4520 family belongs to the CMOS logic hierarchy, where dual counters provide parallel state-holding and event-counting functions without requiring several separate flip-flop packages. Its two counters can be cascaded or operated independently to divide frequency, extend count range, or create multi-stage timing sequences.
The CD4520BE provides two 4-bit counting sections, so each section represents binary values from 0 through 15 before rollover. Interchangeable clock and enable inputs provide flexibility in determining which edge advances the internal D-type flip-flop stages. The carry outputs allow additional counter sections to be cascaded, while the four parallel outputs for each counter expose the current binary state for decoding, event counting, or sequential control.
The implementation uses CMOS stages with internally synchronous counting behavior. Positive-going and negative-going edge operation supports different clocking conventions, while separate enable inputs allow each counter to be held or advanced under independent control. The 16-pin PDIP format provides a conventional through-hole footprint suitable for industrial control, timing, and legacy-compatible logic systems. The manufacturer product page lists the CD4520BE in the active lifecycle state.
Typical uses include frequency division, programmable timing, event and pulse counting, sequential industrial controls, and digital clock or timer subsystems. The dual-counter organization is particularly useful when a design needs two independent count sequences, two cascaded divider stages, or parallel outputs from two counters that can be combined by downstream logic.
Designers should verify the counter's clock-edge requirement, maximum operating frequency, supply-voltage range, and output-drive capability against the manufacturer datasheet before setting timing margins. Input signals must remain within the specified CMOS logic levels, unused inputs should not be left floating, and decoupling should follow the datasheet's recommended application circuit. Cascade connections should be checked for propagation-delay accumulation across multiple stages.
This page combines manufacturer specifications, package and lifecycle information, application guidance, comparison parameters, and verified drop-in alternatives. It also highlights where timing, electrical limits, or functional differences must be checked before substituting another member of the CD4520 family.
Аналоги без доработки для CD4520BE — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
CD4520BEE
✅ Прямая замена ⚠️ Характеристики не проверены📋 Справочный аналог (нет в каталоге)
CD4520BEG4
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
CD4520BE
✅ Прямая заменаУточнить цену
Открыть даташит →CD4520BE Максимальные параметры и электрические характеристики
| Product Type | CMOS dual binary up-counter |
| Counter Elements | 2 counters |
| Counter Width | 4 bits per counter |
| Counter Stages | 4 stages per counter |
| Counting Direction | Up-count |
| Clock Edge Sensitivity | Positive-going or negative-going |
| Тип выхода | Parallel binary outputs with carry |
| Counter Type | Internally synchronous binary counter |
| Диапазон рабочих температур | -55°C to 125°C |
| Корпус | 16-lead PDIP (N) |
| Число выводов | 16 pins |
| Тип монтажа | Through-hole |
| Статус жизненного цикла | Active |
| Статус RoHS | Compliant |
| Manufacturer Lead Time | 3-7 business days |
| Datasheet Length | 13 pages |
Конфигурация выводов CD4520BE
| Контакт 1 | CLOCK A — Clock input for counter A |
| Контакт 2 | ENABLE A — Enable input for counter A |
| Контакт 3 | Q1 A — Least significant output for counter A |
| Контакт 4 | Q2 A — Counter A output |
| Контакт 5 | Q3 A — Counter A output |
| Контакт 6 | Q4 A — Most significant output for counter A |
| Контакт 7 | CARRY A — Carry output for counter A |
| Контакт 8 | VDD — Positive supply voltage |
| Контакт 9 | CARRY B — Carry output for counter B |
| Контакт 10 | Q4 B — Most significant output for counter B |
| Контакт 11 | Q3 B — Counter B output |
| Контакт 12 | Q2 B — Counter B output |
| Контакт 13 | Q1 B — Least significant output for counter B |
| Контакт 14 | ENABLE B — Enable input for counter B |
| Контакт 15 | CLOCK B — Clock input for counter B |
| Контакт 16 | VSS — Ground reference |
Типичное применение
CD4520BE подходит для 6 применениеs: Binary Frequency Divider, Industrial Pulse Counting, Programmable Sequential Timer, Digital Clock Divider, Event Counter and Display Control, Automated Control Retiming.
Binary Frequency Divider
The CD4520BE is appropriate for dividing a repetitive input frequency by 16 because each of its two 4-bit sections provides a 4-stage binary count. One section can divide a clock into a lower-rate pulse train while the other handles a second channel or provides a cascaded stage. The manufacturer describes internally synchronous 4-stage counters with interchangeable clock and enable lines, allowing either clock-edge polarity. Before setting the switching rate, verify the maximum operating frequency, supply voltage, and propagation delay in the manufacturer datasheet.
Рекомендуется
Industrial Pulse Counting
The CD4520BE can count qualified machine events when each pulse represents one completed cycle, movement, or actuation. Its two independent 4-bit counters allow separate event channels or a cascaded 8-bit total, while parallel outputs make intermediate states available to control logic. The active-high or active-low edge flexibility helps accommodate different sensor-conditioning arrangements. For industrial use, the -55°C to 125°C rating is useful, although safety, EMC, and input-protection requirements must be addressed at the system level.
Рекомендуется
Programmable Sequential Timer
The CD4520BE fits sequential timer designs that need two independent 4-bit count sequences, because each counter exposes four parallel outputs and a carry transition. Those outputs can represent elapsed intervals, select delay taps, or advance a state machine after a preset number of clock events. Independent enable inputs allow one sequence to pause while the other continues. Check timing margins against the manufacturer propagation-delay specifications, especially when several stages or external gate delays contribute to the critical path.
Рекомендуется
Digital Clock Divider
A CD4520BE can derive lower-frequency timing signals from a higher-frequency oscillator while offering two counting paths for cascaded division. In a clock system, one section may produce a divided reference and the second may establish a second phase or delayed count. Its selectable positive-going or negative-going clock transition supports common digital timing conventions. The design should include suitable oscillator startup, supply decoupling, and output buffering, and must verify worst-case timing at the intended supply voltage and temperature.
Рекомендуется
Event Counter and Display Control
The CD4520BE is useful in event-counting systems where a binary counter state must be decoded into decimal display, alarm, or control information. Its two counters can monitor separate event sources, and the four parallel outputs per section provide intermediate binary values for downstream decoding. Because the device counts in binary rather than BCD, a binary-to-decimal decoder is required before driving seven-segment displays directly. Account for propagation delay through that decoder when determining when the displayed value is stable.
Рекомендуется
Automated Control Retiming
The CD4520BE can divide machine timing intervals and provide taps for control sequencing in automated equipment. Two independent 4-bit counters allow separate timing chains without adding another dual-counter package, while carry outputs support expansion into a longer sequence. The -55°C to 125°C operating range suits extended industrial environments, but enclosure temperature, power quality, and electromagnetic conditions remain system constraints. Add signal conditioning at sensor inputs and use Schmitt-trigger logic when noisy edges could otherwise cause multiple count transitions.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для CD4520BE — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар | CD4520BEE | CD4520BEG4 | CD4520BE |
|---|---|---|---|---|
| Package | 16-lead PDIP (N) | 16-lead PDIP | 16-lead PDIP | 16-lead PDIP |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Harris Corporation |
| Counter Configuration | Dual 4-bit binary up-counter | Dual 4-bit binary up-counter | Dual 4-bit binary up-counter | Dual 4-bit binary up-counter |
| Counter Elements | 2 counters | 2 counters | 2 counters | 2 counters |
| Counter Width | 4 bits per counter | 4 bits per counter | 4 bits per counter | 4 bits per counter |
Ключевые отличия
- Two independent four-bit counting sections in one package (против CD4518BE)
- Interchangeable clock and enable inputs (против CD4518BE)
- Extended-temperature 16-lead PDIP option (против CD4520BEG4)
Заметки по проектированию
Do not substitute CD4518BE for CD4520BE without changing the system interpretation. CD4520BE produces binary counts, whereas CD4518BE produces BCD counts; the physical counter positions and clocking structure are closely related, but the encoded values differ after count state 9. Review existing decoder logic, alarm thresholds, and software state mapping before approving a cross-family replacement.
Treat every count transition as a potentially repeated edge if the clock source is noisy or has slow transitions. Use clean logic-level drive for CLOCK and ENABLE inputs, and insert a Schmitt-trigger stage when the source is mechanical, open-collector, or long. Maintain the input levels specified by the manufacturer and account for propagation delay in cascaded counter chains so an intermediate carry cannot be sampled before it has settled.
Place the device so clock and enable traces remain short, especially when counting high-frequency events. Route the two counter sections separately when independent timing is required, and keep the ground return path continuous beneath and around the package. Connect supply decoupling according to the manufacturer application circuit and avoid long supply traces between the bypass capacitor and the device.
Verify the supply-voltage range, input thresholds, output-drive capability, and maximum operating frequency in the manufacturer datasheet before finalizing the counter clock. CMOS counter current depends on operating frequency and transition rate, so a low-frequency design does not guarantee the same loading as a high-speed one. Use the datasheet's worst-case supply and timing conditions for the intended operating environment.
Информация о соответствии
RoHS compliance and the -55°C to 125°C operating range are stated in the product listing. No additional REACH, lead-free, halogen-free, conflict-minerals, or automotive qualification claims were established.
