ATMEGA48A-AU - 8-bit AVR MCU, 4KB Flash, 20MHz, TQFP-32 | Microchip
部品番号: ATMEGA48A-AU ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $3.2 | $3.20 |
| 10 | $2.85 | $28.50 |
| 100 | $2.4 | $240.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.78 | $1,780.00 |
ATMEGA48A-AU 概要
An 8-bit AVR microcontroller is a single-chip computer built on the Atmel/Microchip AVR RISC architecture, executing one instruction per clock cycle to deliver deterministic throughput per MHz. AVR MCUs occupy a node in the embedded hierarchy between simple 8051-class controllers and 32-bit ARM Cortex-M devices, offering a balance of code density, peripheral richness, and ease of programming through the AVR/GCC toolchain and Atmel Studio/MPLAB X environments. The ATmega family spans 4 KB to 256 KB Flash variants; the ATmega48A represents the smallest-memory, lowest-pin-count member suitable for compact, cost-sensitive applications.
Key features of the ATMEGA48A-AU include three flexible timer/counters with compare modes, a 10-bit ADC, an analog comparator, a byte-oriented 2-wire (I2C-compatible) serial interface, a programmable USART, an SPI peripheral, six PWM channels, and internal interrupt sources. It also provides 6 sleep modes for power-critical applications, hardware multiplier support, and a watchdog timer with separate on-chip oscillator for maximum reliability.
The architecture combines Harvard-style memory organization (separate Flash program memory and SRAM data memory) with a 2-stage instruction pipeline, ensuring most instructions complete in a single clock cycle. The peripheral set maps directly onto classic AVR register layouts, simplifying firmware porting within the ATmega48/88/168 family and the broader megaAVR line.
Typical applications include consumer electronics, sensor node platforms, industrial control modules, battery-powered instrumentation, hobbyist and maker projects (Arduino-compatible derivatives), and small home appliances. The wide operating voltage and low-power sleep modes also suit unattended remote sensor installations.
When designing with the ATMEGA48A-AU, ensure decoupling capacitors are placed within 5 mm of the VCC and AVCC pins, and that the RESET pin is pulled up through a 10 kohm resistor for stable operation. Programming is supported via ISP (in-circuit serial programming) on the MOSI/MISO/SCK pins, enabling firmware updates after PCB assembly.
This page synthesizes real-time distributor pricing, verified drop-in alternatives from Microchip and competitor families, and practical design notes not consolidated on any single manufacturer or distributor page.
ドロップイン代替品: ATMEGA48A-AU — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: ATMEGA48A-AU （同一形状・フットプリント） — 相違点: Package, Instruction Set, Program Memory Size, Core Architecture, Serial Interfaces.
クイック比較ツール — 並列比較する代替部品を選択:
ATMEGA88A-AU
✅ ドロップイン✓ 在庫あり
$1.52 / 個
データシートを見る →ATMEGA168A-AU
✅ ドロップイン✓ 在庫あり
$1.42 / 個
データシートを見る →ATMEGA48P-AU
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ATMEGA48A-MU
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ATMEGA48PB-AUR
✅ ドロップイン✓ 在庫あり
$0.39 / 個
データシートを見る →ATMEGA48V-10AUR
✅ ドロップイン✓ 在庫あり
$1.82 / 個
データシートを見る →ATMEGA48A-AU 最大定格＆電気的特性
| Core Architecture | AVR 8-bit RISC |
| 最大クロック周波数 | 20 MHz |
| MIPS Throughput | 20 MIPS |
| Program Memory (Flash) | 4 KB (2K x 16) |
| Data EEPROM | 256 B |
| Data SRAM | 512 B |
| General-Purpose I/O Lines | 23 |
| General-Purpose Working Registers | 32 |
| Supply Voltage (VCC) | 4.5 V to 5.5 V |
| 動作温度 | -40 C to +85 C |
| ADC Resolution | 10-bit |
| ADC Channels | 8 |
| Timer/Counters | 3 (with compare modes) |
| PWM Channels | 6 |
| Communication Interfaces | SPI, TWI (I2C), USART |
| パッケージ | 32-pin TQFP (7x7 mm) |
| 実装タイプ | Surface Mount |
| MSLレベル | 3 (168 hours) |
| RoHS ステータス | Compliant |
ATMEGA48A-AU ピン構成
| ピン 1 | PD3 — Port D bit 3 (GPIO / INT1 / OC2B / XCK1) |
| ピン 2 | PD4 — Port D bit 4 (GPIO / T0 / XCK0) |
| ピン 3 | GND — Ground |
| ピン 4 | VCC — Digital supply voltage |
| ピン 5 | GND — Ground |
| ピン 6 | VCC — Digital supply voltage |
| ピン 7 | PB6 — Port B bit 6 (GPIO / XTAL1 / TOSC1) |
| ピン 8 | PB7 — Port B bit 7 (GPIO / XTAL2 / TOSC2) |
| ピン 9 | PD5 — Port D bit 5 (GPIO / OC0B / T1) |
| ピン 10 | PD6 — Port D bit 6 (GPIO / OC0A / AIN0) |
| ピン 11 | PD7 — Port D bit 7 (GPIO / OC2A / AIN1) |
| ピン 12 | PB0 — Port B bit 0 (GPIO / PCINT0 / CLKO) |
| ピン 13 | PB1 — Port B bit 1 (GPIO / OC1A / PCINT1) |
| ピン 14 | PB2 — Port B bit 2 (GPIO / OC1B / SS / PCINT2) |
| ピン 15 | PB3 — Port B bit 3 (GPIO / MOSI / OC2A / PCINT3) |
| ピン 16 | PB4 — Port B bit 4 (GPIO / MISO / PCINT4) |
| ピン 17 | PB5 — Port B bit 5 (GPIO / SCK / PCINT5) |
| ピン 18 | AVCC — Analog supply voltage |
| ピン 19 | ADC6 — ADC input channel 6 (analog only) |
| ピン 20 | AREF — ADC reference voltage |
| ピン 21 | GND — Ground (analog) |
| ピン 22 | ADC7 — ADC input channel 7 (analog only) |
| ピン 23 | PC0 — Port C bit 0 (GPIO / ADC0 / PCINT8) |
| ピン 24 | PC1 — Port C bit 1 (GPIO / ADC1 / PCINT9) |
| ピン 25 | PC2 — Port C bit 2 (GPIO / ADC2 / PCINT10) |
| ピン 26 | PC3 — Port C bit 3 (GPIO / ADC3 / PCINT11) |
| ピン 27 | PC4 — Port C bit 4 (GPIO / ADC4 / SDA / PCINT12) |
| ピン 28 | PC5 — Port C bit 5 (GPIO / ADC5 / SCL / PCINT13) |
| ピン 29 | PC6 — Port C bit 6 (GPIO / RESET / PCINT14) |
| ピン 30 | PD0 — Port D bit 0 (GPIO / RXD / PCINT16) |
| ピン 31 | PD1 — Port D bit 1 (GPIO / TXD / PCINT17) |
| ピン 32 | PD2 — Port D bit 2 (GPIO / INT0 / PCINT18) |
主な用途
ATMEGA48A-AU の用途: 7 件s: Industrial Sensor Node, Hobbyist / Maker Projects (Arduino-compatible), Consumer Appliance Control, Battery-Powered Remote Sensor, USB HID / CDC Device Firmware, Automotive Interior Auxiliary Module, Educational MCU Trainer Board.
Industrial Sensor Node
The ATMEGA48A-AU fits industrial sensor nodes because its 20 MHz 8-bit core, 23 GPIO, and 10-bit ADC sample temperatures, pressures, and digital inputs while staying within tight BOM budgets. With 4 KB Flash, 512 B SRAM, and 256 B EEPROM it accommodates MODBUS RTU or simple proprietary protocol stacks running over the on-chip USART. The 4.5-5.5 V supply matches 5 V industrial rails directly, eliminating an LDO, and the 6 PWM channels drive indicator LEDs or actuator MOSFETs without external timer ICs. The six sleep modes (down to sub-microamp current) allow battery-backed remote nodes to last years on a single cell. Compared with discrete logic, the ATmega48A-AU integrates timers, ADC, and EEPROM into one TQFP-32 chip, shrinking the PCB and improving reliability in vibration-prone cabinets.
おすすめ
Hobbyist / Maker Projects (Arduino-compatible)
The ATMEGA48A-AU serves as a low-cost core for hobbyist boards and Arduino-compatible designs because it runs the same GCC AVR toolchain and ISP programming protocol as the more famous ATmega328P. Its 4 KB Flash and 512 B SRAM are enough for sensor reads, LED chasers, servo controllers, and beginner firmware, while the 23 GPIO directly drive common peripherals like HC-SR04 sonar, WS2812 LEDs, and character LCDs. The TQFP-32 package breaks out to standard 0.1 inch headers via carrier boards. Compared with the ATmega328P-AU, the ATmega48A-AU trades program memory for cost - sketches must stay under 4 KB but unit price is roughly half, ideal for mass hobby kits and education packs. The internal 8 MHz calibrated oscillator eliminates an external crystal for timing-tolerant projects.
おすすめ
Consumer Appliance Control
The ATMEGA48A-AU is well-suited for consumer appliance control boards - washing machine UI boards, microwave keypads, and air-conditioner remotes - because its 32-pin TQFP footprint drops directly onto legacy ATmega48 PCB layouts and the 4 KB Flash handles typical UI firmware plus state machines. Hardware PWM drives LED indicators and buzzer tones; the on-chip 10-bit ADC reads thermistor and potentiometer inputs without an external mux. Six sleep modes allow standby power consumption below 1 uA, satisfying ENERGY STAR no-load limits for white goods. Compared with bare 8051 designs, the AVR RISC core executes most instructions in one clock cycle, simplifying real-time UI response. The 256-byte EEPROM stores user settings through power cycles without an external memory chip.
おすすめ
Battery-Powered Remote Sensor
The ATMEGA48A-AU powers battery-operated wireless sensor nodes - soil moisture probes, weather stations, and LoRaWAN endpoints - by leveraging six sleep modes that drop current below 1 uA in power-down mode. The 4.5-5.5 V supply accepts three alkaline cells or a regulated 5 V rail; for 3.3 V systems, the ATmega48V-10AU variant provides 1.8-5.5 V operation at 10 MHz. The USART and SPI peripherals interface directly with UART-based LoRa, NBIoT, and Sub-GHz radio modules; the 10-bit ADC digitizes battery voltage and sensor inputs without external components. The internal 8 MHz calibrated oscillator eliminates an external crystal on timing-tolerant nodes, saving cost and board space. Compared with discrete logic designs, the ATmega48A-AU integrates timers, ADC, EEPROM, and sleep control into one chip, doubling battery life.
おすすめ
USB HID / CDC Device Firmware
The ATMEGA48A-AU can implement low-speed USB HID and CDC firmware using the V-USB (formerly AVR-USB) software stack, because it offers the timers, external interrupt, and I/O flexibility needed for bit-banged USB on D+/D- lines. With 4 KB Flash, HID reports and basic enumeration fit comfortably; for CDC-to-serial bridges, the 512 B SRAM is adequate for short packet buffers. The 20 MHz core processes USB polling at the required 1.5 Mbps low-speed bit rate with margin. Compared with native-USB AVR parts like the ATmega32U4, the ATmega48A-AU requires a handful of discrete components (3.3 V zener for D-, 1.5 kohm pull-up on D+) but costs roughly a third of the price. This makes it ideal for low-cost keyboard dongles, macros pads, and educational USB tools.
おすすめ
Automotive Interior Auxiliary Module
Although the ATMEGA48A-AU is not AEC-Q100 qualified, it serves as a low-cost auxiliary controller for non-safety automotive interior electronics - HVAC mode switches, ambient lighting drivers, and seat-position memory buttons - within the automotive cabin environment. Its -40 C to +85 C industrial operating range covers cabin temperatures under normal use, and its robust 5 V supply tolerance rejects 12 V bus transients when paired with a simple LDO or TVS. The 23 GPIO and 6 PWM channels drive RGB ambient LEDs and capacitive touch buttons; the TWI interface reads digital temperature sensors and EEPROM-stored trim settings. Compared with AEC-Q100 automotive MCUs (ATmega48A-AUR auto grade, several times more expensive), the ATMEGA48A-AU delivers equivalent functionality for non-safety applications where qualification cost is uneconomical.
おすすめ
Educational MCU Trainer Board
The ATMEGA48A-AU is an excellent microcontroller for educational labs and university embedded-systems courses because it offers the full AVR peripheral set - timers, ADC, PWM, USART, SPI, TWI - at the lowest possible cost per learning platform. The TQFP-32 package and 7 mm x 7 mm footprint keep breakout boards small, and standard ISP pins (MOSI/MISO/SCK/RESET) allow in-circuit programming with $5 AVR ISP clones. Students can develop code in Atmel Studio or PlatformIO using the GCC AVR toolchain and immediately see results on GPIO, ADC, and PWM pins. Compared with the ATmega328P used in Arduino Uno, the ATMEGA48A-AU enforces Flash discipline and pushes students to learn memory-mapped peripherals without the Arduino abstractions. The 4 KB Flash and 512 B SRAM constraints become a teaching feature, not a limitation.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: ATMEGA48A-AU — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | ATMEGA88A-AU | ATMEGA168A-AU | ATMEGA48P-AU | ATMEGA48A-MU | ATMEGA48PB-AU | ATMEGA48V-10AU |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | TQFP-32 (7x7) | TQFP-32 (7x7) - same | TQFP-32 (7x7) - same | TQFP-32 (7x7) - same | QFN-32 (different mechanical outline, same die) | TQFP-32 (7x7) - same | TQFP-32 (7x7) - same |
| Program Memory (Flash) | 4 KB | 8 KB | 16 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| Data SRAM | 512 B | 1 KB | 1 KB | 512 B | 512 B | 512 B | 512 B |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 10 MHz |
| 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 | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V |
| PicoPower Features | Standard | Standard | Standard | Yes (picoPower) | Standard | Yes (picoPower) | Standard |
| Approx. Unit Price (qty 100) | USD 2.40 | USD 2.65 | USD 2.95 | USD 2.55 | USD 2.55 | USD 2.70 | USD 2.30 |
主な差別化要因
- Lowest-cost entry point in the classic ATmega family （vs ATMEGA88A-AU)
- Industrial temperature range with simple 5 V supply （vs ATMEGA48V-10AU)
- Drop-in scalable to ATmega168A without PCB change （vs ATMEGA168A-AU)
- RoHS-compliant and lead-free reflow capable （vs ATMEGA48 (legacy non-A revision))
設計ノート
Place a 100 nF decoupling capacitor within 5 mm of each VCC/AVCC pin and a 10 uF bulk capacitor on the supply rail. The ATmega48A-AU has four supply pins (VCC at pins 4 and 6, AVCC at pin 18, plus analog ground at pin 21) that must all be properly decoupled. AVCC and VCC may be tied together or separately regulated; if separated, AVCC must not differ from VCC by more than +/- 0.3 V per the datasheet. The AREF pin (20) requires a 100 nF capacitor when using AVCC as ADC reference, or an external reference voltage if higher accuracy is needed.
When laying out the TQFP-32 footprint, keep traces on PB3 (MOSI), PB4 (MISO), PB5 (SCK), and RESET (PC6) short and direct to the ISP header, because long traces degrade programming reliability and introduce noise on these signal pins. Route the ADC inputs (PC0-PC5, ADC6, ADC7) away from digital switching traces; use a ground pour under analog traces and a single-point analog ground tie. The XTAL1 (PB6) and XTAL2 (PB7) traces should be short and symmetric, surrounded by grounded copper on both sides.
Avoid the common mistake of using PB6/PB7 as GPIO when the external crystal oscillator is enabled by fuse bits - the pins become disabled for digital I/O. Also, when migrating from ATmega48/88/168 (non-A revisions), note that the A-revision datasheets are separate documents; verify SPI timing against the 40002061 datasheet, not the original ATmega48 datasheet. The pin-1 dot on the TQFP-32 is at the top-left when oriented with the bevel edge down; reversing the orientation shorts VCC to GND through the pin-1 ESD diode.
The internal 8 MHz RC oscillator is factory-calibrated to within +/- 10% of nominal, but the in-system calibration routine (OSCCAL register) can trim it to within +/- 1% using the UART as a timing reference. For applications requiring accurate serial timing, plan for an external crystal on PB6/PB7; the typical HC-49S crystal with 22 pF load capacitors provides +/- 50 ppm accuracy suitable for UART communication above 9600 baud. Low-frequency 32.768 kHz crystals on TOSC1/TOSC2 (PB6/PB7 shared) are supported for RTC applications in asynchronous timer mode.
コンプライアンス情報
RoHS compliant per Microchip product page. Lead-free reflow profile up to 260 C per JEDEC J-STD-020. Not AEC-Q100 qualified - choose ATmega48A-AUR (auto grade suffix) or ATmega328P-AUR for AEC-Q100 automotive applications. The 'A' revision supersedes the legacy non-A ATmega48/88/168 and is RoHS compliant by design.
