CD4045BE - 21-Stage CMOS Counter | Texas Instruments
料号： CD4045BE ✓ 量产中CD4045BE 概述
A CMOS counter is a sequential logic device that records the number and sequence of input-clock transitions. The CD4045 belongs to the broader logic IC hierarchy: counter -> sequential logic -> digital logic -> integrated circuit. Its 21 internal stages permit division of an input frequency by large powers of two, while separate output-shaping circuitry produces a predictable waveform with a stated 3.125% duty cycle.
The principal features include 21 counting stages, a 3 V to 18 V supply range, operation up to 30 MHz, negative-edge counting, and push-pull outputs from the inverter drivers. According to the manufacturer product information, the CD4045B family is 100% tested for quiescent current at 20 V with 5 V, 10 V, and 15 V parametric ratings. The family also meets the stated JEDEC Tentative Standard No. 13B requirements for B-series CMOS devices.
The architecture separates the frequency-counting chain from the output-shaping section. Input inverters support oscillator use, while the output-shaping flip-flops and push-pull inverter drivers provide a defined 3.125% output duty cycle. This combination makes the device more specialized than a conventional binary ripple counter: it combines division, waveform shaping, and output drive in one timing circuit.
Typical uses include digital frequency dividers, clock-generation and crystal-oscillator circuits, programmable timing modules, pulse-generation systems, industrial counters, and battery-powered digital equipment. Its CMOS implementation is particularly appropriate where low static dissipation is valuable, while the 3 V to 18 V supply range supports multiple legacy logic voltage rails.
When designing around the CD4045BE, account for the 16-pin PDIP footprint, the 21-stage division capability, and the output-shaping function rather than treating it as a conventional 16-bit counter. Follow the manufacturer's pin-description and timing diagrams when assigning output stages, and provide appropriate bypass capacitance and a clean clock source to avoid counting errors or unstable oscillator operation.
This page organizes the CD4045BE specifications, sourcing information, replacement constraints, application guidance, and practical design considerations in one place. It also distinguishes true same-footprint replacements from logic devices that are only functionally similar, helping engineers select parts without confusing division capability, output duty-cycle behavior, package fit, and supply-voltage requirements.
直接替换替代料： CD4045BE ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
CD4045BEE4
✅ 直接替换📋 参考替代料（不在目录中）
CD4045BE4
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
CD4045BE 最大额定值与电气特性
| Product Type | CMOS 21-stage counter and timing circuit |
| Counting Stages | 21 stages |
| Logic Family | 4000-series CMOS |
| Supply Voltage Range | 3 V to 18 V |
| Maximum Operating Frequency | 30 MHz |
| Counting Edge | Negative edge |
| Counter Element Count | 1 element |
| Counter Width | 21 bits |
| Output-Shaping Flip-Flops | 2 flip-flops |
| Inverter Output Drivers | 2 push-pull drivers |
| Output Duty Cycle | 3.125% |
| 封装 | PDIP-16 |
| 引脚数量 | 16 pins |
| 安装类型 | Through-hole |
| 工作温度范围 | -55 °C to +125 °C |
| Quiescent Current Test Voltage | 20 V |
| Parametric Test Voltages | 5 V, 10 V, and 15 V |
| Quiescent Current Test Coverage | 100% tested |
| B-Series CMOS Qualification | Meets JEDEC Tentative Standard No. 13B |
CD4045BE pdip-16 引脚配置指南
CD4045BE（pdip-16 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： CD4045BE.
请参阅 数据手册 以查看完整引脚配置。
典型应用
CD4045BE 适用于 6 应用s: Programmable Digital Frequency Divider, Crystal-Controlled Timing Module, Industrial Pulse and Tone Generator, Digital Counter and Rate-Measuring Circuit, Battery-Powered Digital Instrument, Digital Control and Retiming Subsystem.
Programmable Digital Frequency Divider
The CD4045BE fits frequency-division designs because it combines 21 serial counting stages with dedicated output-shaping flip-flops. A clock applied to the counting section can be divided by successive powers of two, while the shaping stage creates a waveform with a stated 3.125% duty cycle. With operation from 3 V to 18 V and support up to 30 MHz, the device is useful in timing and frequency-reduction modules that must preserve a stable, ordered clock waveform. Designers should select the appropriate stage output, allow for propagation delay, and verify the maximum clock rate under the actual supply-voltage and temperature conditions.
推荐
Crystal-Controlled Timing Module
The CD4045BE can support crystal-oscillator timing because its architecture includes input inverters, 21 counting stages, and two output-shaping flip-flops. Those functions allow a crystal network to be combined with a divider and a defined-output waveform in a compact timing circuit. The 3 V to 18 V operating range supports several legacy CMOS supply systems, while the 30 MHz capability covers timing frequencies commonly used in digital instrumentation. Component selection around the oscillator network, output loading, and startup behavior should follow the manufacturer timing diagrams and application guidance.
推荐
Industrial Pulse and Tone Generator
The CD4045BE is suitable for industrial pulse-generation and tone-generation systems because its internal stages provide extensive frequency division and its output-shaping circuitry produces a 3.125% duty-cycle waveform. These functions are useful when a fixed reference must become a lower-rate repetitive signal for sequencing, relay timing, or test equipment. Its 16-pin PDIP format simplifies insertion and replacement in through-hole control boards, while its -55 °C to +125 °C stated range supports demanding environments. Engineers should still verify supply tolerance, clock-jitter requirements, and output-load limits against the manufacturer electrical characteristics.
推荐
Digital Counter and Rate-Measuring Circuit
The CD4045BE can form the basis of a digital counter or low-rate event-counting circuit by using its 21-stage counter chain to reduce an input pulse train to a manageable rate. The negative-edge counting behavior and dedicated shaping stage help establish predictable output timing for downstream control logic. Its CMOS construction supports low static dissipation, making the device suitable for portable or low-power laboratory equipment operating within its 3 V to 18 V range. The input signal must meet the required logic levels and timing margins, and the selected stage output should be checked for adequate output-drive margin.
推荐
Battery-Powered Digital Instrument
The CD4045BE is appropriate for battery-powered digital instruments because the CD4045B family targets applications requiring ultra-low dissipation or battery-source operation. Its CMOS counter architecture operates from 3 V to 18 V and can divide and shape a low-power clock while maintaining low static consumption. The 16-pin PDIP package is useful for prototypes, repair assemblies, and through-hole instrument boards where socketed or manually inserted logic is preferred. Designers should minimize unused-output loading, select suitable bypass capacitors, and confirm quiescent-current and operating-temperature limits in the manufacturer datasheet for the final power budget.
推荐
Digital Control and Retiming Subsystem
The CD4045BE can serve as a retiming and sequencing element when a system requires a stable divided clock rather than direct pass-through of a noisy or irregular timing signal. Its 21 stages offer multiple division points, while the two output-shaping flip-flops and push-pull drivers provide a defined output waveform for downstream logic. This makes it useful in legacy industrial controllers, test fixtures, and pulse-processing boards built around through-hole CMOS logic. Layout should keep clock routing short, provide local supply bypass, and account for counter-edge timing and propagation delay between the input and selected stage outputs.
推荐
推荐产品汇总
工程参考数据： CD4045BE ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | CD4045BEE4 | CD4045BE4 |
|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | PDIP-16 | PDIP-16 | PDIP-16 |
| Product Type | CMOS 21-stage counter and timing circuit | CMOS 21-stage counter and timing circuit | CMOS 21-stage counter and timing circuit |
| Counting Stages | 21 stages | 21 stages | 21 stages |
| Supply Voltage Range | 3 V to 18 V | 3 V to 18 V | 3 V to 18 V |
| Maximum Operating Frequency | 30 MHz | 30 MHz | 30 MHz |
| Output Duty Cycle | 3.125% | 3.125% | 3.125% |
| Counting Edge | Negative edge | Negative edge | Negative edge |
| Output-Shaping Flip-Flops | 2 flip-flops | 2 flip-flops | 2 flip-flops |
| Special Features | Input inverters, 2 push-pull inverter output drivers, and 3.125% shaped output | Input inverters, 2 push-pull inverter output drivers, and 3.125% shaped output | Input inverters, 2 push-pull inverter output drivers, and 3.125% shaped output |
关键差异点
- Combines division and dedicated waveform shaping （对比 CD4020BK)
- Deep 21-stage counter chain （对比 CD4060BK)
- Broad CMOS supply range （对比 CD4045BEE4)
设计说明
Place the supply bypass capacitor close to the device's VDD and VSS connections, and keep the clock input return path short. The CD4045B family is specified for a 3 V to 18 V supply and is 100% tested for quiescent current at 20 V, but the actual switching current depends on clock activity and output loading. Keep unused output loads minimal and verify the power budget at the highest expected clock frequency.
Use a clean, monotonic clock edge and preserve the input rise and fall times required by the manufacturer timing characteristics. The counter advances on a negative edge, so ringing or an extra transition near the threshold can produce an erroneous count. Route the oscillator or clock source away from switching nodes, provide a local ground return, and test the assembled board with a scope when the design relies on high division ratios or precise pulse timing.
Follow the manufacturer package drawing for the 16-pin PDIP footprint and its lead pitch. Confirm whether the exposed ordering suffix uses a straight or formed lead configuration before laying out the board, because mechanically similar 16-pin packages may not share identical dimensions. Maintain adequate clearance around the IC, avoid accidental solder bridges between adjacent pins, and provide unobstructed access for through-hole assembly and rework.
Do not treat CD4045BE as a conventional binary counter or substitute a generic ripple counter solely because both devices count clock pulses. The CD4045BE includes 21 counting stages, two output-shaping flip-flops, two push-pull inverter drivers, and input inverters. Substitution can change output logic, duty cycle, timing, and pin functions even when the broad application appears similar.
Assign stage outputs according to the manufacturer description and avoid long branches between the clock source and counting chain. When multiple stage outputs are used, isolate sensitive loads with suitable series impedance or buffer stages if rise times are too slow. The push-pull output drivers are intended to provide defined signals, but external fanout and loading still affect timing margins and should be checked against the electrical characteristics.
合规信息
Texas Instruments states that CD4045B meets JEDEC Tentative Standard No. 13B for B-series CMOS devices. Specific RoHS, REACH, lead-free, halogen-free, and conflict-minerals declarations are not stated in the referenced product-page content.
