ATMEGA808-MF - 8-Bit AVR MCU 20MHz 8KB Flash | Microchip
MPN： ATMEGA808-MF ✓ 啟用中ATMEGA808-MF 概覽
A microcontroller (MCU) is a single-chip computer integrating a processor core, program memory, data memory, and peripherals on one die. Within the hierarchy of semiconductor devices, the MCU sits at the application layer of embedded systems: an 8-bit AVR core is a RISC architecture well suited to cost-sensitive control tasks, sitting above bare logic ICs and below 32-bit ARM-based application processors. The megaAVR 0-series is Microchip's modernized AVR family built on Core Independent Peripherals (CIPs).
Key features of the ATMEGA808-MF include the AVR RISC CPU with a hardware multiplier executing most instructions in a single cycle, 20 MHz maximum clock frequency, 8 KB of self-programmable Flash memory, 1 KB of SRAM, and 256 bytes of EEPROM for parameter retention. Core Independent Peripherals such as TCA/TCB timers, the Analog-to-Digital Converter (ADC), analog comparators, and configurable custom logic (CCL) offload tasks from the CPU, reducing latency and code complexity.
Technically, the megaAVR 0-series introduces a new peripheral set with event system routing, allowing peripherals to communicate without CPU intervention. The device supports single-cycle I/O access, multi-level interrupt vectors, and an CRC-checked boot process. Memory is organized as Harvard architecture with separate program and data buses.
Typical applications include industrial control and automation nodes, Functional Safety (FuSa) oriented designs, home appliances, motor control interfaces, and embedded sensing systems where 8 KB of code space and rich analog peripherals are sufficient.
Design consideration: the -MF variant is specified for 4.5V to 5.5V operation to reach the full 20 MHz clock; for lower-voltage or battery designs, the wide-voltage -MN variant (down to 1.8V) should be evaluated instead.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 ATMEGA808-MF — 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。
此系列的變體
與下列產品可直接替換的同系列型號： ATMEGA808-MF （相同外形與佔位） — 差異在於 Core Processor, Programming Interface, Flash Memory, SRAM, Package.
ATMEGA1608-MF
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA3208-MF
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA4808-MF
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA808-MN
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
ATMEGA808-MF 最大額定值與電氣特性
| Core Processor | AVR (8-bit RISC with hardware multiplier) |
| Core Size | 8-Bit |
| Max Clock Frequency | 20 MHz |
| Flash Memory | 8 KB (8K x 8) |
| SRAM | 1 KB |
| EEPROM | 256 bytes |
| Supply Voltage Range | 4.5 V to 5.5 V |
| 封裝 | 32-VQFN (5x5 mm) |
| 安裝類型 | Surface Mount |
| Product Series | megaAVR 0 (ATmega808) |
| Functional Safety | FuSa qualified (safety documentation available) |
| Programmable I/O Count | 27 GPIO |
| Peripherals | Core Independent Peripherals (CIP), event system, ADC, analog comparator, CCL, PWM timers |
| 工作溫度 | -40C to +105C |
| Oscillator Type | Internal oscillator and external clock options |
| Programming Interface | Unified Program and Debug Interface (UPDI) |
| RoHS 狀態 | Compliant |
ATMEGA808-MF 腳位配置
| 腳位 1 | PA0 — GPIO / UPDI (Unified Program and Debug Interface) |
| 腳位 2 | PA1 — GPIO / ADC input |
| 腳位 3 | PA2 — GPIO / ADC input |
| 腳位 4 | PA3 — GPIO / ADC input |
| 腳位 5 | PA4 — GPIO / ADC input |
| 腳位 6 | PA5 — GPIO / ADC input |
| 腳位 7 | PA6 — GPIO / ADC input |
| 腳位 8 | PA7 — GPIO / ADC input |
| 腳位 9 | VDD — Power supply (4.5 V to 5.5 V) |
| 腳位 10 | GND — Ground |
| 腳位 11 | PB0 — GPIO / TCB input capture |
| 腳位 12 | PB1 — GPIO |
| 腳位 13 | PB2 — GPIO / analog comparator input |
| 腳位 14 | PB3 — GPIO / analog comparator input |
| 腳位 15 | PB4 — GPIO |
| 腳位 16 | PB5 — GPIO |
| 腳位 17 | PC0 — GPIO / TCA PWM output |
| 腳位 18 | PC1 — GPIO / TCA PWM output |
| 腳位 19 | PC2 — GPIO / TCA PWM output |
| 腳位 20 | PC3 — GPIO / TCA PWM output |
| 腳位 21 | PC4 — GPIO / TCA PWM output |
| 腳位 22 | PC5 — GPIO / TCA PWM output |
| 腳位 23 | PC6 — GPIO / USART / SPI |
| 腳位 24 | PC7 — GPIO / USART / SPI |
| 腳位 25 | PD0 — GPIO / USART / TWI |
| 腳位 26 | PD1 — GPIO / USART / TWI |
| 腳位 27 | PD2 — GPIO / USART |
| 腳位 28 | PD3 — GPIO / USART |
| 腳位 29 | PD4 — GPIO |
| 腳位 30 | PD5 — GPIO |
| 腳位 31 | PD6 — GPIO / RESET (active-low reset input) |
| 腳位 32 | PD7 — GPIO |
典型應用
ATMEGA808-MF 適用於 6 應用s: Industrial Control and Automation, Functional Safety (FuSa) Systems, Home Appliances, Motor Control Interfaces, Embedded Sensing and IoT Nodes, Human Interface and Lighting Control.
Industrial Control and Automation
The ATMEGA808-MF fits industrial control nodes because its Core Independent Peripherals (CIPs) run timers, PWM, and analog comparisons without CPU intervention, and its 4.5V-5.5V supply range matches standard industrial 5V rails. The 20 MHz AVR core with hardware multiplier executes control loops with single-cycle I/O access, while the event system routes sensor triggers directly to timer capture, achieving microsecond-scale response. Placed as a PLC I/O module controller or sensor node, it handles sequencing, debouncing, and PWM actuator drive deterministically; the trade-off is the modest 1 KB SRAM, which limits buffering and rules out complex protocol stacks.
推薦
Functional Safety (FuSa) Systems
The ATMEGA808-MF is explicitly qualified as a megaAVR 0-series Functional Safety (FuSa) part, with Microchip providing safety manuals and failure-rate documentation supporting IEC 61508 and ISO 13849 compliance projects. Its hardware watchdog (WDT) with windowed mode, brown-out detector (BOD), and Flash CRC scan provide the self-diagnostic primitives safety designs require. Used in safety-related shut-off logic or light-curtain controllers, the 20 MHz core executes diagnostic routines within cycle budgets, and the 5V rail gives high noise immunity in electrically harsh panels. Designers must still implement system-level diagnostics per the Microchip safety manual; the FuSa qualification reduces but does not eliminate certification effort.
推薦
Home Appliances
Appliance control boards - cooktops, washing machines, coffee makers - benefit from the ATMEGA808-MF's combination of 27 GPIO, ADC, analog comparators, and Core Independent Peripheral PWM in a compact 5x5 mm VQFN. The 4.5V-5.5V operation tolerates the noisy, sagging supplies typical of appliance power stages, and the -40C to +105C temperature range covers kitchen environments. Timers drive triac firing and relay sequencing via PWM without CPU load, while the ADC reads NTC thermistors for closed-loop temperature control. The 8 KB Flash accommodates state machines and UI logic; appliances needing richer HMI code should use the drop-in ATMEGA1608-MF or ATMEGA3208-MF in the same footprint.
推薦
Motor Control Interfaces
The ATMEGA808-MF serves small motor control tasks where its TCA timers generate complementary PWM outputs and the analog comparator with configurable hysteresis implements overcurrent protection in hardware. At 20 MHz, the single-cycle AVR core closes current-loop feedback fast enough for brushed DC and small BLDC fan motors when paired with an external gate driver. The event system connects comparator outputs directly to timer fault shutdown without software latency - a CIP-based safety path. The 5V domain interfaces cleanly to gate-driver logic inputs; note that the ADC's sampling rate limits it to low-bandwidth control, so high-performance FOC drives should move to a dsPIC or ARM-based solution.
推薦
Embedded Sensing and IoT Nodes
With an internal ADC, analog comparators, 256 bytes of EEPROM for calibration constants, and low-power sleep modes, the ATMEGA808-MF is well suited to wired sensor nodes and sub-GHz IoT endpoints. The CCL configurable logic can gate sensor interrupts so the CPU wakes only on qualified events, cutting average current in battery-backed designs. Data from the ADC or external sensors is stored in the 1 KB SRAM and packetized for a serial link (USART) to a radio module. The 8 KB Flash fits sensor drivers plus a lightweight protocol; secure TLS-class stacks require a companion secure element. Designers targeting 3V coin-cell operation should select the wide-voltage ATMEGA808-MN instead.
推薦
Human Interface and Lighting Control
The ATMEGA808-MF drives capacitive-touch-adjacent UI boards, LED dimmers, and backlit control panels using its multi-channel TCA PWM outputs and CIP-based waveform generation. At 5V, LED string current regulation via PWM achieves smooth 8-bit dimming without CPU intervention, while the ADC reads potentiometers or ambient-light sensors for closed-loop brightness control. The 32-pin VQFN's 27 GPIO handle keypads, encoders, and status indicators on a single controller, replacing discrete logic and reducing BOM cost. The -40C to +105C rating suits enclosed luminaires where heat concentrates; verify that self-heating plus ambient keeps the junction within limits per the datasheet thermal data.
推薦
推薦產品摘要
工程參考資料，適用於 ATMEGA808-MF — 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 | ATMEGA1608-MF | ATMEGA3208-MF | ATMEGA4808-MF | ATMEGA808-MN |
|---|---|---|---|---|---|
| Package | 32-VQFN (5x5 mm) | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Max Frequency | AVR 8-bit, 20 MHz | AVR 8-bit, 20 MHz | AVR 8-bit, 20 MHz | AVR 8-bit, 20 MHz | AVR 8-bit, 20 MHz (derated at low VDD) |
| Flash Memory | 8 KB | 16 KB | 32 KB | 48 KB | 8 KB |
| SRAM | 1 KB | 1 KB | 2 KB | 6 KB | 1 KB |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Functional Safety (FuSa) | Yes | Yes | Yes | Yes | Yes |
主要差異化特點
- Lowest-cost entry point of the 32-pin megaAVR 0 family (對比ATMEGA4808-MF)
- 5V-native noise immunity with full 20 MHz speed (對比ATMEGA808-MN)
- FuSa safety qualification in the smallest memory tier (對比ATMEGA1608-MF)
設計說明
The -MF speed grade is only guaranteed at 4.5V-5.5V. If your board also must run from a 3.3V rail (for example when sharing a supply with USB logic), the ATMEGA808-MF is out of spec - select the wide-voltage ATMEGA808-MN instead and derate the clock per the datasheet voltage-frequency curve. Decouple each VDD pin with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk 4.7 uF-10 uF capacitor per supply domain, as recommended in the megaAVR 0-series hardware design application notes.
The 32-VQFN (5x5 mm) has a 0.5 mm pitch and an exposed die paddle (EP) on the bottom that must be soldered to a grounded copper pour for mechanical integrity and heat spreading - the ATmega808 does not require the EP electrically, but leaving it unsoldered risks solder-defect reliability issues. Use an array of thermal vias under the paddle. Follow Microchip's QFN land-pattern guideline with approximately 0.3 mm stencil aperture reduction to prevent solder bridging between the 0.5 mm pitch pads.
UPDI shares PA0 with GPIO; do not connect PA0 to other circuitry that could load the single-wire UPDI line, or in-field programming will fail. If RESET (PD6) is repurposed as GPIO, the debug/programming entry window shrinks drastically - keep RESET available or design an external UPDI-accessible test point. The internal oscillator is factory-calibrated but the ATmega808 also supports external clock; confirm fuse/CONFIG settings in MPLAB X before locking configurations, since incorrect UPDI/RESET configuration can require HV recovery.
Route analog inputs (PORTA ADC channels) away from PWM and USART switching traces on PORTC/PORTD to keep ADC noise low; use the event system and CCL to reduce CPU polling activity rather than adding software delays. Keep the VQFN paddle and GND return paths continuous under the clock sources. Estimated: with typical megaAVR 0-series active current of a few mA at 20 MHz/5V, self-heating in the 32-VQFN is minor, but thermal verification against the datasheet theta-JA is advised for dense, enclosed assemblies.
合規資訊
RoHS compliance per standard Microchip green packaging for megaAVR 0-series. REACH, halogen-free, and conflict-minerals status should be confirmed via the official Microchip product environmental page; AEC-Q100 is not applicable (FuSa qualification, not automotive grade, per distributor categorization).
