ATMEGA6450A-AU - 8-bit AVR MCU 64KB 20MHz TQFP-100 | Microchip
MPN： ATMEGA6450A-AU ✓ 啟用中ATMEGA6450A-AU 概覽
An 8-bit AVR ATmega microcontroller belongs to the broader product hierarchy of embedded microcontroller units (MCU), a class of single-chip computers integrating a processor core, program memory, data memory, timers, communication peripherals and general-purpose I/O on one die. The AVR architecture uses Harvard memory mapping with a two-stage pipeline: the ATmega6450A executes 130 powerful instructions, most of which complete in a single clock cycle, delivering up to 20 MIPS throughput at 20 MHz.
Key features include in-system self-programmable Flash with read-while-write capability, a JTAG interface for boundary-scan, on-chip debugging and programming, three flexible 16-bit timer/counters with compare modes, an internal RC oscillator, and 54 general-purpose I/O lines (69 in larger packages of the family). The core operates from a 5 V nominal supply (2.5 V, 3.3 V and 5 V operating points are recognized for the ATmega6450 family), suiting industrial noise-margin designs.
Architecturally, the ATmega6450A combines the AVR enhanced RISC core with 32 general-purpose working registers directly connected to the arithmetic logic unit, allowing one-cycle execution of most instructions. The device also integrates an 8-channel 10-bit ADC, analog comparator, USART serial ports, SPI and two-wire (I2C-compatible) interfaces for full system connectivity.
Typical applications include industrial control panels and HMI front ends, building automation and HVAC controllers, and instrumentation that benefits from the LCD drive capability of the ATmega6450 family and the large 100-pin TQFP pin count.
Design consideration: at 20 MHz and 5 V, ensure the supply is decoupled with 100 nF ceramics at multiple VCC/GND pin pairs of the TQFP-100, and verify the brown-out detector threshold matches your 5 V regulator dropout to prevent Flash corruption during power dips.
This page synthesizes distributor pricing, drop-in family alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 ATMEGA6450A-AU — 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： ATMEGA6450A-AU （相同外形與佔位） — 差異在於 Flash Memory, Core Architecture, Package, SRAM, Working Registers.
ATMEGA6450P-AU
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA6450V-8AU
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →ATMEGA3290A-AU
✅ 直接替換聯絡詢價
查看資料表 →ATMEGA6490P-AU
✅ 直接替換📋 參考替代品（不在目錄中）
ATMEGA6450A-AU 最大額定值與電氣特性
| Core Architecture | 8-bit AVR RISC, 130 instructions |
| 最大時脈頻率 | 20 MHz |
| Peak Throughput | 20 MIPS (at 20 MHz) |
| Flash Memory | 64 KB (32K x 16), ISP, read-while-write |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| General Purpose I/O | 54 / 69 lines |
| Working Registers | 32 x 8-bit |
| 供應電壓 | 2.5 V / 3.3 V / 5 V operating points |
| 封裝 | 100-TQFP (14x14 mm) |
| 安裝類型 | Surface Mount |
| Debug / Programming | JTAG (boundary-scan, on-chip debug), ICSP |
| Timers | Three flexible timer/counters with compare modes |
| Series | AVR ATmega, Industrial grade (IND) |
ATMEGA6450A-AU 100-tqfp (14x14 mm) 腳位配置指南
ATMEGA6450A-AU（100-tqfp (14x14 mm) 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： ATMEGA6450A-AU.
請參閱 資料表 以查看完整腳位配置。
典型應用
ATMEGA6450A-AU 適用於 6 應用s: Industrial Control Panels, HMI / LCD Instrument Front Ends, Building Automation and HVAC Controllers, Battery-Powered Metering, Embedded Test and Prototyping Fixtures, Legacy AVR 5V System Maintenance.
Industrial Control Panels
The ATMEGA6450A-AU fits industrial control panel controllers because its 5 V operating point delivers high noise margin in electrically noisy factory environments, and its 54/69 GPIO lines provide abundant fan-out for relays, indicators and switches. The 20 MHz AVR core executes most of its 130 instructions in one cycle, giving deterministic real-time behavior for sequential control logic. The 64 KB self-programmable Flash supports read-while-write bootloaders for field firmware updates without replacing hardware, and the JTAG interface enables on-chip debugging during commissioning. Design consideration: use the brown-out detector and decouple each VCC/GND pin pair of the 100-TQFP with 100 nF ceramics to ride through sags on shared industrial supply rails.
推薦
HMI / LCD Instrument Front Ends
The ATmega6450 family integrates LCD drive capability that pairs with the ATMEGA6450A-AU's 100-pin TQFP to directly front-end segment-LCD human-machine interfaces in meters and panel instruments. The 2 KB EEPROM stores calibration and user settings through power cycles, while the 4 KB SRAM buffers display frames and measurement logs. Its 10-bit ADC (per family datasheet) digitizes sensor inputs for display scaling, and the three timer/counters with compare modes generate multiplex timing and backlight PWM. Because the whole display controller plus MCU lives on one die, board area and BOM cost drop versus discrete LCD drivers. Verify the exact LCD segment/capacity configuration for the A-version in the Microchip datasheet before finalizing the glass selection.
推薦
Building Automation and HVAC Controllers
HVAC and building automation nodes benefit from the ATMEGA6450A-AU's combination of USART, SPI and two-wire interfaces for networking with sensors and actuators, plus its industrial temperature classification noted by Mouser. The 64 KB Flash accommodates protocol stacks and event logs, and 2 KB EEPROM persists setpoints and schedules across power loss. Timer/counters with compare modes handle valve/PWM actuation and timebase generation, while the internal oscillator option simplifies clock design in cost-sensitive thermostats. The JTAG boundary-scan support aids production test of dense 100-pin boards. Design tip: run the supply at 5 V for sensor-switching noise margin, and implement a watchdog plus brown-out configuration to guarantee recovery from transient mains disturbances.
推薦
Battery-Powered Metering
For battery-operated meters within the ATmega6450 platform, select the picoPower drop-in ATMEGA6450P-AU (same TQFP-100 footprint) or exploit the A-part's idle and power-down sleep modes managed through its AVR power management. The 2 KB EEPROM retains billing data, and the ADC samples load current for energy calculation. Because the device shares its footprint with P- and V- family variants, one PCB supports multiple power/speed SKUs - a supply-chain resilience advantage. Design consideration: for battery designs, prefer the P-variant when sleep current dominates battery budget; the A-version is better for mains-powered meters. Validate the exact sleep-mode current figures against the Microchip ATmega6450A/P datasheet tables before finalizing battery lifetime projections.
推薦
Embedded Test and Prototyping Fixtures
The ATMEGA6450A-AU is a strong fit for bench test fixtures and prototype controllers thanks to JTAG on-chip debugging (breakpoints, single-step) and boundary-scan on all digital pins of the 100-TQFP, which simplifies verifying solder joints and harness wiring. Its 54/69 GPIO lines drive many DUT signals simultaneously, and the 20 MHz core executes stimulus routines deterministically. Read-while-write Flash lets test logs stream to Flash while code runs, and multiple USARTs (per family datasheet) talk to instruments concurrently. Recommended practice: reserve the JTAG port on production-fixtures PCBs, use an external programmer such as MPLAB SNAP per Microchip's ICSP guidance, and add series resistors on GPIO banks to protect against mis-wired DUT connections.
推薦
Legacy AVR 5V System Maintenance
Many installed AVR-based products were designed around 5 V ATmega parts; the ATMEGA6450A-AU serves as a maintenance/second-source controller for such boards needing 64 KB Flash in TQFP-100. Because Microchip continues the AVR ATmega line, the A-series drop-in replaces earlier 64KB-class parts on the same footprint with minimal firmware changes. The device also anchors upgrade paths: ATMEGA6450P-AU drops in for power optimization, and the family comparison data (Utmel/FindIC) confirms cross-compatibility of the 6450/6490 TQFP-100 series. Procurement tip: standardize on one family variant across service inventory to reduce stocking cost, and verify package temperature suffix (industrial -40C to +85C class) matches the field environment per Mouser's IND grade listing.
推薦
推薦產品摘要
工程參考資料，適用於 ATMEGA6450A-AU — 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 | ATMEGA6450P-AU | ATMEGA6450V-8AU | ATMEGA3290A-AU | ATMEGA6490P-AU |
|---|---|---|---|---|---|
| Package | 100-TQFP (14x14 mm) | 100-TQFP (14x14 mm) - same | 100-TQFP (14x14 mm) - same | 100-TQFP (14x14 mm) - same | 100-TQFP (14x14 mm) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 32 KB | 64 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 2 KB | 4 KB |
| Max Clock Frequency | 20 MHz | 20 MHz | 8 MHz | 20 MHz | 20 MHz |
| Power Technology | Standard (A-series) | picoPower | Low-voltage V-series | Standard (A-series) | picoPower |
| EEPROM | 2 KB | 2 KB | 2 KB | 1 KB | 2 KB |
| Core / Instruction Set | AVR 8-bit RISC, 130 instructions | AVR 8-bit RISC, 130 instructions | AVR 8-bit RISC, 130 instructions | AVR 8-bit RISC (compatible) | AVR 8-bit RISC (compatible) |
主要差異化特點
- Full-speed 20 MHz A-series core in the 100-pin family (對比ATMEGA6450V-8AU)
- Lower power option available in the same footprint (對比ATMEGA6450P-AU)
- Double the program memory of the 32KB 100-pin sibling (對比ATMEGA3290A-AU)
設計說明
The 100-TQFP package has multiple VCC/GND pin pairs; connect every one of them and place a 100 nF ceramic capacitor at each pair, plus a 10 uF bulk capacitor near the supply entry. Estimated: transient core current at 20 MHz can spike tens of milliamps within one clock cycle, and distributed decoupling keeps rail droop below the brown-out threshold. If running at 5 V with an upstream switching regulator, set the brown-out detector level so that regulator dropout transients never allow Flash writes below the minimum specified operating voltage.
For the 14x14 mm TQFP-100, use 0.5 mm pitch fan-out rules: via-in-pad or dogbone fan-outs with 0.3 mm drill, and keep crystal traces under 15 mm with ground guard rings. Route JTAG (TCK/TMS/TDI/TDO) as a short, matched group with series resistors if the header is more than 10 cm away. The exposed none of EP - standard TQFP has no pad - so thermal relief relies on copper pours; connect ground pours to all GND pins with multiple vias for low-impedance reference planes.
Three frequent mistakes: (1) clocking above the frequency allowed by the supply voltage - at reduced VCC the maximum safe clock drops; consult the voltage-versus-frequency graph in the Microchip ATmega6450A datasheet. (2) Ignoring the read-while-write restriction: a bootloader writing Flash must execute from the boot section and mask interrupts during page erase/write. (3) Leaving JTAG enabled in production firmware allows boundary-scan access to all pins; disable JTAG via fuse if security matters.
合規資訊
Compliance status not stated in the verified web data. Current Microchip AVR parts are generally RoHS-compliant, but this must be confirmed on the Microchip product page or distributor compliance sheets before claiming.
