W78L801A24PL - 24MHz 8-Bit 8051 MCU with 4KB ROM | Nuvoton
Teilenummer: W78L801A24PL ✓ AktivW78L801A24PL Übersicht
An 8-bit microcontroller is a programmable semiconductor that integrates a processor core, program memory, data memory, and peripherals into one device. The W78L801 belongs to the 8051 family, a widely used embedded-control architecture also known as an MCS-51 microcontroller. Its 4 KB mask ROM stores the fixed firmware program, while its 256-byte RAM supports variables, stack operations, and intermediate working data. Applications generally center on sequential control logic, sensor acquisition, keypad or display control, and communication interfaces.
The principal operating characteristics include a maximum clock frequency of 24 MHz, an 8-bit processing architecture, 4 KB of mask-programmable ROM, and a 1.8 V to 5.5 V supply range. Two software-controlled power modes help conserve energy. Idle mode stops the processor clock while allowing supported peripheral operations to continue, whereas power-down mode stops the crystal oscillator for minimum power consumption. The external clock may also be stopped without affecting processor state according to the W78L801 datasheet.
The W78L801A24PL combines conventional 8051 instruction-set compatibility with a surface-mount LCC implementation. The PL suffix denotes the 44-LCC J-lead package shown in product documentation. Its masked-program architecture is appropriate for high-volume products in which firmware is finalized before production. Because the program memory is mask ROM rather than user-programmable flash, firmware changes normally require a different programmed device rather than an in-circuit update.
Typical uses include industrial controllers, appliance-control boards, instrumentation modules, building equipment, and compact embedded systems that benefit from the low-power operating modes. The 24 MHz clock provides additional processing headroom for time-sensitive control tasks, while the 8051 instruction set supports a compact software ecosystem and established development methods. System-level suitability depends on the selected external clock, memory organization, and peripheral requirements described in the datasheet.
Designers should verify the exact pin functions, oscillator connections, reset behavior, and available I/O assignments against the manufacturer pin-description table before laying out a PCB. Decoupling, clock stability, exposed programming considerations, and supply sequencing also require normal mixed-signal layout practices. Because this package is a leaded LCC rather than a fine-pitch bare die, assembly planning should account for its 44 J-leads.
This page combines the manufacturer-oriented device description with verified product parameters, application guidance, design cautions, and a transparent comparison of what the available technical information establishes. It helps engineers identify whether the W78L801A24PL architecture, memory configuration, clock rate, voltage range, and package align with a new embedded-control design.
Drop-in-Alternativen für W78L801A24PL – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Für dieses Produkt sind keine Drop-in-Alternativen verfügbar.
Alternativen anfordernW78L801A24PL Grenzwerte & elektrische Eigenschaften
| Product Type | 8-bit 8051-compatible microcontroller |
| Maximale Taktfrequenz | 24 MHz |
| Program Memory | 4 KB mask ROM |
| Program Memory Organization | 4K x 8 bits |
| Data Memory | 256 bytes |
| CPU Architecture | 8-bit |
| Processor Family | 8051 / W78 series |
| Operating Voltage Range | 1.8 V to 5.5 V |
| Gehäuse | 44-LCC J-lead |
| Package Pin Count | 44 pins |
| Package Dimensions | 16.6 mm x 16.6 mm |
| Power Reduction Modes | 2 modes: idle and power-down |
| Idle Mode Behavior | Processor clock off; supported peripheral operation continues |
| Power-Down Mode Behavior | Crystal oscillator stopped for minimum power consumption |
| External Clock Control | Can be stopped in any processor state |
| Montageart | Surface mount |
| RoHS-Status | Compliant |
| Datasheet Length | 24 pages |
W78L801A24PL 16.6 mm x 16.6 mm Pinbelegungsleitfaden
Pinbelegung für W78L801A24PL (16.6 mm x 16.6 mm-Gehäuse). Dieser digitale IC umfasst GPIO, Kommunikationsschnittstellen (UART, SPI, I2C) und Versorgungspins. Alternative Pin-Funktionen und Konfigurationsoptionen entnehmen Sie dem Herstellerdatenblatt. Unverzichtbar für Embedded-System-Design und PCB-Layout.
Keine detaillierten Pinbelegungsdaten verfügbar für W78L801A24PL.
Siehe die Datenblatt für die vollständige Pin-Konfiguration.
Typische Anwendungen
W78L801A24PL ist geeignet für 6 Anwendungs: Industrial Control Panels, Appliance and Equipment Control, Sensor Acquisition Modules, Building and Environmental Control, Instrumentation and Metering, Communication Interface Modules.
Industrial Control Panels
The W78L801A24PL fits compact industrial control panels that coordinate digital inputs, outputs, indicators, and local operator actions. Its 8051-compatible 8-bit processor executes deterministic control logic at up to 24 MHz, while 256 bytes of RAM support working variables and stack operations. The 1.8 V to 5.5 V operating range provides flexibility in low-voltage industrial control electronics. Idle mode is useful when the panel periodically wakes to scan inputs but must leave supported peripheral activity running; power-down mode is appropriate when the complete controller can remain inactive.
Appliance and Equipment Control
The W78L801A24PL can serve as the main controller in an appliance, instrument, or equipment-control module with a fixed firmware configuration. Its 4 KB mask ROM is appropriate for production devices whose program is finalized before manufacturing, while the 24 MHz clock provides processing margin for sequential state machines and peripheral coordination. The 44-LCC J-lead package supports surface-mount assembly. Firmware should use the idle mode to reduce processor activity between tasks and the power-down mode when the product is intentionally switched off.
Sensor Acquisition Modules
A W78L801A24PL-based module can sample switches, resistive sensors, and digital sensors through its available I/O and interface resources. The 24 MHz 8-bit core supports timed acquisition and local filtering, while 256 bytes of RAM can hold recent samples, status flags, and stack data. The manufacturer W78L801 datasheet also describes software-selectable idle and power-down modes, enabling a duty-cycled design in which the controller powers down between measurement intervals. Exact sensor-channel counts and peripheral assignments must be confirmed from the pin-description and electrical tables before implementation.
Building and Environmental Control
The W78L801A24PL is suitable for small building-control nodes that supervise relays, inputs, and communication functions requiring a simple deterministic controller. Operation from 1.8 V to 5.5 V supports integration with low-voltage sensor and interface circuitry, while idle mode permits selected peripherals to continue operating without keeping the processor clock active. For battery- or energy-constrained installations, power-down mode stops the crystal oscillator and minimizes consumption. The enclosure design must provide appropriate thermal and environmental protection, and firmware should verify every actuator state after reset.
Instrumentation and Metering
A compact metering or test module can use the W78L801A24PL to perform measurement sequencing, calibration handling, data formatting, and local status reporting. Its 24 MHz maximum clock offers adequate instruction throughput for many sequential 8051 tasks, and the 4 KB mask ROM can hold fixed production firmware. The 256-byte RAM limit makes careful stack and buffer planning important for multi-stage processing. Use the idle mode between measurement activities when peripheral timers must remain active, and use power-down mode only when the complete measurement chain can safely stop.
Communication Interface Modules
The W78L801A24PL can be used in small protocol-conversion or communication-control modules where a compact 8051-compatible core handles framing, command parsing, and status reporting. Its 24 MHz clock supports timely serial character processing, while 1.8 V to 5.5 V operation permits integration with modern interface electronics. The mask-ROM configuration is appropriate for fixed protocol implementations deployed in volume. Designers should assign buffering carefully because RAM is limited to 256 bytes and should use idle mode only after confirming that the required communication peripheral can continue running without the processor clock.
Technische Referenzdaten für W78L801A24PL – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Designhinweise
Assign PCB connections from the manufacturer pin-description table in the W78L801 datasheet. The device uses a 44-LCC J-lead footprint, so verify every lead position, oscillator connection, reset input, and I/O assignment against the package drawing before fabrication. Place the supply bypass capacitor adjacent to the appropriate power and ground pins, and use a short, low-inductance path for the decoupling connection.
Operate the W78L801A24PL only within its documented 1.8 V to 5.5 V supply range. Confirm the voltage required by the crystal oscillator and attached peripherals rather than assuming that every external device supports the same rail. If the external clock can be stopped, verify in firmware that resuming or changing clock state cannot create a transient outside the device's electrical limits.
Treat the 4 KB mask ROM as a production-time programming choice, not user-updatable flash. Validate the complete firmware image and device ordering configuration before committing to production. Because RAM is limited to 256 bytes, control stack depth, avoid large local arrays, and minimize simultaneous buffering in interrupt and main-loop routines.
Keep the oscillator path compact and position the crystal and associated capacitors according to the manufacturer reference layout. Route sensitive timing and sensing signals away from switching nodes and high-current return paths. The LCC package's J-leads allow visual solder-joint inspection, but the board footprint must still be checked for lead location, courtyard clearance, and assembly-handling requirements.
Compliance-Informationen
The LCSC product listing identifies the W78L801A24PL as RoHS compliant. Other compliance characteristics are not confirmed in the retrieved technical information.
