W78ERD2A40FL - 40MHz 64KB 8052 MCU | Nuvoton | BQFP
MPN： W78ERD2A40FL ✓ 啟用中W78ERD2A40FL 概覽
An 8-bit microcontroller is a programmable semiconductor containing a central processing unit, program memory, data memory, peripheral registers, and I/O ports on one integrated circuit. Within the product hierarchy, the W78ERD2A40FL is a general-purpose MCU, an embedded controller, and a member of the Nuvoton W78 family. Its 8052-compatible core provides a practical migration path for applications using standard 8051-class peripherals and software conventions.
The principal advantages of this device are its 40 MHz clock rating, 64 KB flash organization, 36 available I/O lines, and dedicated boot-block storage. The 6T process designation identifies the manufacturing process used for the integrated circuit, while the Programmable Counter Array provides dedicated timing and capture functions that can reduce reliance on software polling. Four 8-bit I/O ports follow the established 8052 peripheral model, including software-selectable internal pull-ups on Port 0.
Technically, the W78ERD2A40FL combines a fast 8-bit core with separate program and data memory regions. The 64 KB program memory is organized as 64K by 8 bits, while the 1.25 KB data RAM is organized as 1.25K by 8 bits. Its power-down mode can be entered without disrupting the processor state, supporting systems that need low-energy operating states. The device is intended for a 5 V operating environment and is identified as lead-free by the manufacturer product listing.
Typical applications include industrial keypad and panel controllers, small motor-control systems, programmable timers, data-acquisition front ends, communication peripherals, legacy 8052 equipment, and embedded automation controllers. The 36 I/O lines provide useful connection density for switches, displays, sensors, actuators, and external bus devices in compact industrial control boards.
A principal design consideration is the 5 V supply and the need to confirm clock, reset, memory-access, and peripheral connections against the manufacturer pin-description table. Designers should preserve the intended oscillator and decoupling arrangements, keep high-current outputs away from sensitive inputs, and budget timing margin when using the 40 MHz clock rating in a specific system.
This product page consolidates the verified core specifications, package information, family alternatives, application guidance, and design considerations for engineers evaluating the W78ERD2A40FL. The comparison section emphasizes where closely related W78 devices differ in clock speed, while the practical notes focus on firmware migration, peripheral planning, decoupling, and PCB implementation.
直接替換替代品，適用於 W78ERD2A40FL — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
W78ERD2A30FL
✅ 直接替換📋 參考替代品（不在目錄中）
W78ERD2A20FL
✅ 直接替換📋 參考替代品（不在目錄中）
W78ERD2A40FL 最大額定值與電氣特性
| Product Type | 8-bit CMOS microcontroller |
| Core Compatibility | 8052 instruction-set compatible |
| Maximum Operating Frequency | 40 MHz |
| Program Memory Size | 64 KB (64K x 8) |
| Program Memory Type | Flash |
| Boot Block Size | 4 KB |
| RAM Size | 1.25 KB (1.25K x 8) |
| Number of I/O | 36 lines |
| I/O Port Configuration | Four 8-bit I/O ports |
| Port 0 Internal Pull-Ups | Enabled by software |
| 供應電壓 | 5 V |
| 封裝 | 44-BQFP |
| 安裝類型 | Surface mount |
| Programmable Counter Array | Supported |
| Process Technology | 6T |
| Power-Down Mode | Supported without affecting the processor |
| Lead-Free Status | Lead-free |
W78ERD2A40FL 44-bqfp 腳位配置指南
W78ERD2A40FL（44-bqfp 封裝）的腳位配置。 此數位 IC 包含 GPIO、通訊介面（UART、SPI、I2C）與電源腳位。替代腳位功能與配置選項請參閱製造商資料表。對嵌入式系統設計與 PCB 佈局至關重要。
無詳細腳位定義資料： W78ERD2A40FL.
請參閱 資料表 以查看完整腳位配置。
典型應用
W78ERD2A40FL 適用於 6 應用s: Industrial Keypad and Panel Control, Programmable Timer and Event Controller, Small Motor and Actuator Control, Data Acquisition Front End, Legacy 8052 Equipment Upgrade, Embedded Automation Controller.
Industrial Keypad and Panel Control
The W78ERD2A40FL fits keypad, selector, and operator-panel controllers because its 40 MHz 8052-compatible core provides processing headroom while four 8-bit ports supply 36 usable I/O lines. Software-controlled Port 0 pull-ups simplify open-drain-style bus interfaces where appropriate. A typical design scans switch matrices, drives indicators, handles debouncing, and communicates with a supervisor controller. The 64 KB flash and 1.25 KB RAM provide room for interface tables and state logic, while the 44-BQFP keeps the controller compact. Confirm pin multiplexing, oscillator routing, and external bus timing against the family datasheet before finalizing the board.
推薦
Programmable Timer and Event Controller
The W78ERD2A40FL is appropriate for timing and event-control systems that benefit from both a 40 MHz clock and a dedicated Programmable Counter Array. The PCA can support repeated timing, capture, and event-oriented operations while the 8052-compatible core handles sequencing and communications. Thirty-six I/O lines allow the controller to combine input capture, outputs, status lamps, and an external interface. Its 64 KB flash supports event tables and firmware updates, while power-down mode can reduce activity during long idle periods. The exact PCA channels, interrupt vectors, and alternate pin functions must be assigned from the manufacturer pin and peripheral tables.
推薦
Small Motor and Actuator Control
The W78ERD2A40FL can serve as the supervisory controller in compact motor or actuator modules where deterministic 8052-family timing and numerous digital I/O lines are more important than a high-precision analog control loop. Its 40 MHz processing speed supports state-machine execution, position counting, fault latching, and communication with a dedicated power stage. The four 8-bit ports provide enough parallel connectivity for limit sensors, step-command signals, enable lines, and status feedback. Use the Programmable Counter Array for compatible timing tasks, but keep high-current switching and protection circuitry outside the MCU package.
推薦
Data Acquisition Front End
The W78ERD2A40FL is suitable as a digital front end for sensors and converters that produce serial or parallel data requiring local control, buffering, and protocol handling. The 40 MHz clock allows efficient acquisition loops and communication routines, while 36 I/O lines can carry sensor selects, converter strobes, data buses, and status signals. Its 64 KB flash can hold calibration tables and protocol handlers, and the 1.25 KB RAM supports short frame buffers. The MCU should remain separate from high-energy analog paths; use suitable signal conditioning, grounding, and isolation according to the transducer interface and environmental requirements.
推薦
Legacy 8052 Equipment Upgrade
The W78ERD2A40FL is useful for maintaining or modernizing equipment built around 8052-class firmware because it supports the standard 80C52 instruction set and the 80C52 pin-compatible architecture. Engineers can retain application logic while using 64 KB flash, a 4 KB boot block, and a 40 MHz clock. The 44-BQFP package supports conventional surface-mount assembly, and four 8-bit ports preserve familiar I/O organization. Migration still requires register-level peripheral checks, boot-memory consideration, oscillator validation, and a complete pin assignment check rather than assuming every legacy timing behavior is unchanged.
推薦
Embedded Automation Controller
The W78ERD2A40FL fits small automation controllers that coordinate sensors, relays, indicators, and communications over multiple digital ports. Its 40 MHz 8052-compatible core can implement control algorithms while the Programmable Counter Array handles compatible repetitive timing tasks. The 64 KB program memory supports structured application code, and power-down mode can lower activity when the controller is waiting for an external event. A robust design should include hardware reset, supply filtering, watchdog or supervisory support where available, and safe output states. Verify available watchdog, communications, and interrupt resources directly from the family documentation.
推薦
推薦產品摘要
工程參考資料，適用於 W78ERD2A40FL — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | W78ERD2A30FL | W78ERD2A20FL |
|---|---|---|---|
| Package | 44-BQFP | 44-BQFP | 44-BQFP |
| Brand | Nuvoton Technology Corporation | Nuvoton Technology Corporation | Nuvoton Technology Corporation |
| Maximum Operating Frequency | 40 MHz | 30 MHz | 20 MHz |
| Clock Difference from Target | 40 MHz | 10 MHz lower, 25% reduction | 20 MHz lower, 50% reduction |
| Processor Architecture | 8-bit 8052-compatible CMOS microcontroller | W78ERD2A family 8-bit microcontroller | W78ERD2A family 8-bit microcontroller |
主要差異化特點
- Highest verified clock rating in the identified W78ERD2A alternatives (對比W78ERD2A30FL)
- More processing headroom than the 20 MHz family option (對比W78ERD2A20FL)
- Established 64 KB flash configuration (對比W78ERD2A30FL)
設計說明
Do not treat the 30 MHz and 20 MHz W78ERD2A family alternatives as automatic substitutes in a timing-critical 40 MHz design. Review baud-rate generation, timer reload values, sampling intervals, bus-cycle assumptions, and busy-wait loops because changing the clock ratio can alter real-time behavior. Reconfirm memory configuration, boot-block use, peripheral availability, and package pin assignments in the manufacturer documentation before releasing a substitution.
Route the 5 V supply and ground using a low-impedance distribution network, place local decoupling close to the device power pins, and avoid sharing narrow return paths with switching loads. Keep clock, reset, and high-speed serial routes away from noisy motor and relay wiring. The 44-BQFP footprint needs careful fan-out routing, but pin-assignment work should be based on the official pin-description table because the package drawing alone does not define peripheral functions.
The W78ERD2A40FL is intended for a 5 V supply and includes a power-down mode for reduced activity during idle periods. Design the supply for the device's specified current and transient requirements, including margin for attached I/O loads. Use reset and brownout behavior appropriate to the application, and ensure every externally connected pin cannot drive the MCU beyond its allowable voltage during reset or power-down states.
Assign the four 8-bit ports and PCA functions only after checking alternate peripheral mappings. Software-controlled Port 0 pull-ups can support compatible bus arrangements, but external pull-ups and signal loading still require electrical review. For mixed analog and digital designs, partition sensitive inputs from relay, power-converter, and communication circuits, use a deliberate grounding strategy, and test edge rates and ringing with a high-bandwidth probe at the actual MCU pins.
合規資訊
The Nuvoton product listing identifies the W78ERD2A40FL as lead-free. Separate RoHS, REACH, AEC-Q100, halogen-free, and conflict-minerals declarations are not stated in the available product information.
