W79E352AFG - 8-bit 8051 MCU, 24MHz, 8KB Flash, 44-QFP | Nuvoton
MPN: W79E352AFG ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.55 | $35.50 |
| 100 | $3.15 | $315.00 |
| 500 | $2.8 | $1,400.00 |
| 1,000 | $2.5 | $2,500.00 |
W79E352AFG Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory (ROM/Flash), data memory (RAM), and I/O peripherals into one package. The 8051 architecture, originally introduced by Intel in 1980 and now maintained by Nuvoton and others, sits within the broader hierarchy: microcontroller -> embedded processor -> digital IC -> semiconductor. The W79E352AFG belongs to Nuvoton's W79 series, optimized for cost-sensitive industrial control, home appliance, and motor drive front-ends.
Key features of the W79E352AFG include up to 36 general-purpose I/O pins, multiple communication interfaces (EBI/EMI, I2C, UART/USART), four 16-bit timer/counters, hardware PWM channels, and an in-system programmable (ISP) Flash that enables firmware upgrades without removing the device from the board. Operating voltage spans 2.4 V to 5.5 V, supporting both 3.3 V and 5 V system designs with a single device.
Technically, the part uses a single-cycle 8051 core that executes most instructions in 1 to 4 clocks (versus 12 in the original 8051), yielding roughly 4x to 12x higher effective MIPS than legacy designs. The integrated 4 KB auxiliary Flash area allows bootloader/ISP separation from the application code region. On-chip RC oscillator options reduce external BOM, and configurable GPIO drive strength simplifies interface to relays, MOSFETs, or 5 V peripheral logic.
Typical applications include BLDC and stepper motor control (using the PWM and timer modules), home appliances (washing machines, induction cookers, microwave ovens), industrial control boards, low-end sensor hubs, and replacement of legacy 8051 designs where pin compatibility, code compatibility, and an upgrade path to ISP Flash are required.
When designing in this part, reserve pin 30 (RST) for an external reset network and ensure the VDD-to-VSS decoupling is placed within 5 mm of the package. Designers moving from older Nuvoton N79E352ADG (44-DIP) parts can reuse existing firmware because the W79E352AFG shares the same SFR map.
This page synthesizes distributor pricing, drop-in alternatives, package diagrams, and practical design notes that complement the official Nuvoton datasheet for engineers migrating legacy 8051 designs or evaluating the W79 series for new industrial and appliance projects.
Drop-in alternatives for W79E352AFG — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
W79E352ADG
✅ Drop-In📋 Reference alternative (not in catalog)
W79E352RAFG
✅ Drop-In📋 Reference alternative (not in catalog)
N79E352AFG
✅ Drop-In📋 Reference alternative (not in catalog)
W78E052D
✅ Drop-In📋 Reference alternative (not in catalog)
W78E058D
✅ Drop-In📋 Reference alternative (not in catalog)
W79E352AFG Maximum Ratings & Electrical Characteristics
| Core Architecture | 8051 (MCS-51 compatible) |
| Data Bus Width | 8-bit |
| Maximum Clock Frequency | 24 MHz |
| Program Memory Size | 8 KB (8K x 8) Flash |
| RAM Size | 256 bytes |
| Operating Supply Voltage | 2.4 V to 5.5 V |
| Number of I/O Pins | 36 |
| Package | 44-pin QFP |
| Mounting Type | Surface Mount |
| Peripherals | Brown-out Detect/Reset, LVD, POR, PWM, WDT |
| Connectivity | EBI/EMI, I2C, UART/USART |
| Number of Timers | 4 x 16-bit |
| Operating Temperature | -40 C to +85 C |
| RoHS Status | Compliant |
| Lead Free | Yes |
W79E352AFG Pin Configuration
| Pin 1 | P1.0/T2 — GPIO / Timer 2 external input |
| Pin 2 | P1.1/T2EX — GPIO / Timer 2 trigger |
| Pin 3 | P1.2 — General-purpose I/O |
| Pin 4 | P1.3 — General-purpose I/O |
| Pin 5 | P1.4 — General-purpose I/O |
| Pin 6 | P1.5 — General-purpose I/O |
| Pin 7 | P1.6 — General-purpose I/O |
| Pin 8 | P1.7 — General-purpose I/O |
| Pin 9 | RST — Reset input, active high |
| Pin 10 | P3.0/RXD — GPIO / UART receive |
| Pin 11 | P3.1/TXD — GPIO / UART transmit |
| Pin 12 | P3.2/INT0 — GPIO / External interrupt 0 |
| Pin 13 | P3.3/INT1 — GPIO / External interrupt 1 |
| Pin 14 | P3.4/T0 — GPIO / Timer 0 external input |
| Pin 15 | P3.5/T1 — GPIO / Timer 1 external input |
| Pin 16 | P3.6/WR — GPIO / External data write strobe |
| Pin 17 | P3.7/RD — GPIO / External data read strobe |
| Pin 18 | XTAL2 — Crystal oscillator output |
| Pin 19 | XTAL1 — Crystal oscillator input |
| Pin 20 | VSS — Ground |
| Pin 21 | P2.0/A8 — GPIO / Address bit 8 (EBI) |
| Pin 22 | P2.1/A9 — GPIO / Address bit 9 (EBI) |
| Pin 23 | P2.2/A10 — GPIO / Address bit 10 (EBI) |
| Pin 24 | P2.3/A11 — GPIO / Address bit 11 (EBI) |
| Pin 25 | P2.4/A12 — GPIO / Address bit 12 (EBI) |
| Pin 26 | P2.5/A13 — GPIO / Address bit 13 (EBI) |
| Pin 27 | P2.6/A14 — GPIO / Address bit 14 (EBI) |
| Pin 28 | P2.7/A15 — GPIO / Address bit 15 (EBI) |
| Pin 29 | PSEN — Program store enable (EBI) |
| Pin 30 | ALE — Address latch enable (EBI) |
| Pin 31 | EA/VPP — External access / Flash programming voltage |
| Pin 32 | P0.7/AD7 — GPIO / EBI multiplexed data/address bit 7 |
| Pin 33 | P0.6/AD6 — GPIO / EBI multiplexed data/address bit 6 |
| Pin 34 | P0.5/AD5 — GPIO / EBI multiplexed data/address bit 5 |
| Pin 35 | P0.4/AD4 — GPIO / EBI multiplexed data/address bit 4 |
| Pin 36 | P0.3/AD3 — GPIO / EBI multiplexed data/address bit 3 |
| Pin 37 | P0.2/AD2 — GPIO / EBI multiplexed data/address bit 2 |
| Pin 38 | P0.1/AD1 — GPIO / EBI multiplexed data/address bit 1 |
| Pin 39 | P0.0/AD0 — GPIO / EBI multiplexed data/address bit 0 |
| Pin 40 | VDD — Positive supply voltage |
| Pin 41 | P4.0 — General-purpose I/O / ISP |
| Pin 42 | P4.1 — General-purpose I/O / ISP |
| Pin 43 | P4.2 — General-purpose I/O |
| Pin 44 | P4.3 — General-purpose I/O |
Typical Applications
W79E352AFG is suitable for 6 applications: Home Appliance Motor Control, Induction Cooker and Microwave Oven Controller, Industrial Sensor Hub and Front-End, Smart Metering and Energy Monitoring, Consumer Appliance Remote and Keypad Boards, Automotive Body and Comfort Modules (Non-Safety).
Home Appliance Motor Control
The W79E352AFG fits BLDC and single-phase induction motor control boards in washing machines, range hoods, and small pumps because of its 4 x 16-bit timers, hardware PWM channels, brown-out reset, and 2.4 V to 5.5 V supply tolerance. The 36 GPIOs can drive triac/MOSFET gate signals, read Hall sensors, and multiplex a 7-segment or LCD user interface. With 8 KB ISP Flash, firmware can be updated in the field without opening the appliance housing, a critical feature for after-sale service.
Recommended
Induction Cooker and Microwave Oven Controller
Induction cookers and microwave ovens need a 5 V-tolerant 8051 MCU with strong EMC immunity, PWM for IGBT drive, and reliable resets during line transients. The W79E352AFG delivers all three through its LVD, brown-out detect, and 16-bit PWM timers running from a stable internal RC oscillator. The 8 KB Flash holds the safety logic, and the 256 B RAM is sufficient for the small state machines typical in cooker control firmware without requiring external SRAM.
Recommended
Industrial Sensor Hub and Front-End
The W79E352AFG is a natural fit for industrial 4-20 mA / 0-10 V sensor front-ends and Modbus RTU over UART, where the 8051 core, I2C, and UART/USART peripherals let one device aggregate multiple sensors while remaining pin-compatible with legacy Nuvoton designs. Operating from 2.4 V to 5.5 V allows it to ride through industrial supply dips. The ISP Flash enables remote firmware updates across thousands of deployed hubs without truck rolls.
Recommended
Smart Metering and Energy Monitoring
Single-phase energy meter designs use the W79E352AFG to compute RMS current/voltage, drive LCD segments, and report over UART or I2C. The brown-out reset and watchdog timer are critical for safety certifications, while 8 KB of Flash provides ample room for calibration constants and tamper detection logic. The 44-QFP package allows standard SMT lines to be used for high-volume meter production.
Recommended
Consumer Appliance Remote and Keypad Boards
Remotes, washing-machine keypads, and air-conditioner wall modules typically use a low-cost 8051 with UART or I2C to talk to a main controller. The W79E352AFG fits perfectly: 36 GPIOs scan key matrices, the UART or I2C interface connects back to the main board, and the 2.4 V minimum supply supports 2 x AA battery operation with a simple LDO. ISP Flash simplifies late-stage firmware personalization per model SKU.
Recommended
Automotive Body and Comfort Modules (Non-Safety)
In non-safety automotive subsystems such as seat controllers, mirror adjusters, or HVAC actuators, the W79E352AFG's 5 V tolerance, hardware PWM, and watchdog timer support brushed DC motor drive and LED driver control. AEC-Q100 is not qualified, so this part is recommended only for interior comfort modules where functional safety is not mandated, and the supply rail is well regulated.
Recommended
Recommended Products Summary
Engineering reference data for W79E352AFG — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | W79E352ADG | W79E352RAFG | N79E352AFG | W78E052D |
|---|---|---|---|---|---|
| Brand | Nuvoton Technology Corporation | Nuvoton Technology Corporation | Nuvoton Technology Corporation | Nuvoton Technology Corporation | Nuvoton Technology Corporation |
| Package | 44-QFP | 44-DIP | 44-QFP - same | 44-QFP - same | 44-QFP - same |
| Core | 8051 (1T/4T) | 8051 (1T/4T) | 8051 (1T/4T) | 8051 (1T/4T) | 8051 (4T) |
| Clock Frequency | 24 MHz | 24 MHz | 24 MHz | 24 MHz | 40 MHz |
| Flash Memory | 8 KB | 8 KB | 16 KB | 8 KB | 8 KB |
| RAM Size | 256 B | 256 B | 512 B | 256 B | 256 B |
| I/O Pins | 36 | 36 | 36 | 36 | 36 |
| Operating Voltage | 2.4 V to 5.5 V | 2.4 V to 5.5 V | 2.4 V to 5.5 V | 2.4 V to 5.5 V | 2.4 V to 5.5 V |
Key Differentiators
- Field-upgradeable ISP Flash (vs W78E052D)
- Doubled RAM in same package (vs W79E352RAFG)
- Industrial supply tolerance (vs W78E058D)
Design Notes
Decouple VDD (pin 40) with a 0.1 uF ceramic capacitor placed within 5 mm of the package, paired with a bulk 10 uF electrolytic or tantalum capacitor on the same node. The 8051 core draws fast transient currents; insufficient decoupling causes spurious brown-out resets under PWM switching loads. Keep analog/digital grounds joined at a single star point under the IC.
Route the RST line (pin 9) away from PWM and high-current switching traces. Place the reset pull-up (typically 10 kohm) and 0.1 uF reset capacitor as close to pin 9 as possible. For ISP programming via UART, expose P3.0 (RXD, pin 10) and P3.1 (TXD, pin 11) on a header or test pad; many production designs also break these out to a 2.54 mm header for in-system firmware updates.
Estimated: assuming a 24 MHz crystal with 20 pF load caps, the XTAL pins typically need 10 to 33 pF NPO/C0G capacitors selected for the specific crystal's load specification. Do not use X7R or electrolytic capacitors on XTAL - their temperature drift pulls the oscillator off-frequency and can cause UART communication errors.
The QFP-44 package has a junction-to-ambient thermal resistance of approximately 80 C/W. At 24 MHz with all peripherals active, total supply current is typically 15 to 25 mA, dissipating well under 150 mW even at 5.5 V. Standard SMT land patterns with at least 1 oz copper pours are sufficient; no heatsink is required.
Compliance Information
RoHS compliant per Nuvoton product page; AEC-Q100 not qualified - do not use in safety-critical automotive subsystems. REACH and conflict-mineral declarations should be confirmed with Nuvoton directly via their product compliance portal.
