ATMEGA168A-AU - 8-Bit AVR MCU 16KB Flash 20MHz | Microchip
部品番号: ATMEGA168A-AU ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $2.19 | $2.19 |
| 10 | $1.98 | $19.80 |
| 100 | $1.76 | $176.00 |
| 500 | $1.58 | $790.00 |
| 1,000 | $1.42 | $1,420.00 |
ATMEGA168A-AU 概要
An AVR microcontroller is a Harvard-architecture 8-bit RISC device that executes most instructions in a single clock cycle, sitting in the hierarchy of microcontroller -> embedded processor -> integrated circuit -> semiconductor. The ATmega168A family is the second-generation "A" revision of the classic ATmega168, adding improved brown-out detection, a calibrated internal RC oscillator, and enhanced EEPROM endurance while retaining full pin and code compatibility with the original ATmega168 and the picoPower ATmega168P/PA devices.
Key features include 16 KB ISP flash with read-while-write capability, 512 B EEPROM rated for 100,000 write/erase cycles, 1 KB internal SRAM, 23 programmable I/O lines, 32 general-purpose working registers, three flexible timer/counters with compare modes, a serial programmable USART, a byte-oriented Two-Wire serial interface, and an SPI serial port. The device also integrates a 10-bit ADC, a programmable watchdog timer with internal oscillator, and six sleep modes for low-power operation.
The ATmega168A uses Microchip's high-performance, low-power AVR 8-bit RISC architecture with 131 powerful instructions, most executing in a single clock cycle, achieving throughput approaching 1 MIPS per MHz. This allows the system designer to optimize power consumption versus processing speed. The 32-TQFP package measures 7x7 mm with a 0.8 mm pitch, making it suitable for compact surface-mount assemblies.
Typical applications include Arduino-compatible development boards, industrial sensor nodes, battery-powered IoT endpoints, motor control, home automation, and portable instrumentation. The wide 2.7 V to 5.5 V supply range supports both 3.3 V and 5 V logic systems, and the integrated peripherals reduce external component count.
When designing with this device, decouple VCC and AVCC with 100 nF ceramic capacitors placed close to the pins, and connect the AREF pin through a low-pass filter when using the ADC. The RESET pin requires an external pull-up or the internal pull-up must be enabled.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, providing engineers with a single reference for selection, replacement, and layout decisions.
ドロップイン代替品: ATMEGA168A-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: ATMEGA168A-AU （同一形状・フットプリント） — 相違点: Operating Temperature, ADC Resolution, Timers/Counters, Communication Interfaces, Timers.
クイック比較ツール — 並列比較する代替部品を選択:
ATMEGA168PA-AU
✅ ドロップイン✓ 在庫あり
$0.98 / 個
データシートを見る →ATMEGA168-20AU
✅ ドロップイン✓ 在庫あり
$1.82 / 個
データシートを見る →ATMEGA168A-AUR
✅ ドロップイン✓ 在庫あり
$1.45 / 個
データシートを見る →ATMEGA168PA-AUR
✅ ドロップイン✓ 在庫あり
$1.85 / 個
データシートを見る →ATMEGA328P-AU
✅ ドロップイン✓ 在庫あり
$1.74 / 個
データシートを見る →ATMEGA88PA-AU
✅ ドロップイン✓ 在庫あり
$1.21 / 個
データシートを見る →ATMEGA168A-AU 最大定格＆電気的特性
| Core Architecture | 8-bit AVR RISC |
| Program Memory Size | 16 KB (8K x 16) Flash |
| Program Memory Type | Flash (ISP, read-while-write) |
| EEPROM Size | 512 B |
| SRAM Size | 1 KB |
| 最大クロック周波数 | 20 MHz |
| Operating Voltage Range | 2.7 V to 5.5 V |
| Number of I/O Lines | 23 |
| General Purpose Registers | 32 |
| Instruction Set | 131 instructions, most single-cycle |
| Timers/Counters | 3 (two 8-bit, one 16-bit) with compare modes |
| Serial Interfaces | USART, SPI, Two-Wire (I2C) |
| ADC Resolution | 10-bit |
| パッケージ | 32-TQFP (7x7 mm) |
| 実装タイプ | Surface Mount |
| 動作温度 | -40 C to +85 C |
| Sleep Modes | 6 (Idle, ADC Noise Reduction, Power-save, Power-down, Standby, Extended Standby) |
| RoHS ステータス | Compliant |
| Lifecycle Stage | Active |
ATMEGA168A-AU ピン構成
| ピン 1 | PD3 — Port D, bit 3 (also INT1, OC2B) |
| ピン 2 | PD4 — Port D, bit 4 (also T0, XCK) |
| 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 (also XTAL1/TOSC1) |
| ピン 8 | PB7 — Port B, bit 7 (also XTAL2/TOSC2) |
| ピン 9 | PD5 — Port D, bit 5 (also T1, OC0B) |
| ピン 10 | PD6 — Port D, bit 6 (also AIN0, OC0A) |
| ピン 11 | PD7 — Port D, bit 7 (also AIN1) |
| ピン 12 | PB0 — Port B, bit 0 (also ICP1, CLKO) |
| ピン 13 | PB1 — Port B, bit 1 (also OC1A) |
| ピン 14 | PB2 — Port B, bit 2 (also OC1B, SS) |
| ピン 15 | PB3 — Port B, bit 3 (also OC2A, MOSI) |
| ピン 16 | PB4 — Port B, bit 4 (also MISO) |
| ピン 17 | PB5 — Port B, bit 5 (also SCK) |
| ピン 18 | AVCC — Analog supply voltage for ADC |
| ピン 19 | ADC6 — Analog input channel 6 |
| ピン 20 | AREF — Analog reference voltage for ADC |
| ピン 21 | GND — Ground |
| ピン 22 | ADC7 — Analog input channel 7 |
| ピン 23 | PC0 — Port C, bit 0 (also ADC0) |
| ピン 24 | PC1 — Port C, bit 1 (also ADC1) |
| ピン 25 | PC2 — Port C, bit 2 (also ADC2) |
| ピン 26 | PC3 — Port C, bit 3 (also ADC3) |
| ピン 27 | PC4 — Port C, bit 4 (also ADC4, SDA) |
| ピン 28 | PC5 — Port C, bit 5 (also ADC5, SCL) |
| ピン 29 | PC6 — Port C, bit 6 (also RESET) |
| ピン 30 | PD0 — Port D, bit 0 (also RXD) |
| ピン 31 | PD1 — Port D, bit 1 (also TXD) |
| ピン 32 | PD2 — Port D, bit 2 (also INT0) |
主な用途
ATMEGA168A-AU の用途: 6 件s: Arduino-Compatible Development Boards, Industrial Sensor Nodes, Battery-Powered IoT Endpoints, Motor Control and Robotics, Home Automation Controllers, Portable Instrumentation.
Arduino-Compatible Development Boards
The ATMEGA168A-AU is the exact MCU used on classic Arduino boards such as the Duemilanove and Diecimila, making it a natural fit for Arduino-compatible designs. Its 16 KB flash accommodates the Arduino bootloader plus a moderate sketch, while the 23 I/O lines map directly to the standard Arduino header layout. The 20 MHz maximum clock and 2.7 V to 5.5 V supply allow operation from either USB 5 V or a 3.3 V regulator. Designers typically pair it with an FT232RL USB-to-serial bridge for programming and a 16 MHz crystal for timing accuracy. The trade-off versus the ATMEGA328P-AU is half the flash and SRAM, so memory-intensive sketches may require the larger device.
おすすめ
Industrial Sensor Nodes
The ATMEGA168A-AU suits industrial sensor nodes because its integrated 10-bit ADC, three timer/counters, and USART/SPI/I2C interfaces connect directly to temperature, pressure, and flow sensors without external interface logic. The -40 C to +85 C operating range covers most factory-floor environments, and the 2.7 V to 5.5 V supply tolerates the noisy rails typical of 24 V industrial systems after regulation. A typical node samples an analog sensor through the ADC, processes the reading, and transmits over RS-485 via the USART. The 16 KB flash limits complex protocol stacks, so designs needing TCP/IP or large buffers should migrate to the ATMEGA328P-AU or a 32-bit MCU.
おすすめ
Battery-Powered IoT Endpoints
For battery-powered IoT endpoints, the ATMEGA168A-AU offers six sleep modes including Power-down and Power-save, allowing average current in the microamp range between transmissions. The 1 KB SRAM and 512 B EEPROM store sensor calibration data and network credentials without external memory. The integrated watchdog timer with independent oscillator improves reliability in unattended deployments. A typical endpoint wakes on a timer, reads a sensor via I2C, and transmits over a sub-GHz or BLE module through the USART or SPI. The main trade-off is that the A-revision draws more standby current than the picoPower ATMEGA168PA-AU, so power-critical designs should select the PA variant.
おすすめ
Motor Control and Robotics
The ATMEGA168A-AU handles motor control and small robotics tasks using its three timer/counters with compare modes to generate PWM for H-bridge drivers. The 16-bit Timer/Counter1 provides precise PWM for motor speed control, while the 10-bit ADC reads potentiometers or current-sense shunts for closed-loop feedback. The 23 I/O lines drive limit switches, encoders, and status LEDs. At 20 MHz the core executes most instructions in one cycle, giving responsive control-loop timing. Designers should note that the 16 KB flash constrains complex motion-planning algorithms, so multi-axis robots typically use the ATMEGA328P-AU or a 32-bit device. Decouple the motor supply from the MCU rail to avoid brown-out resets.
おすすめ
Home Automation Controllers
The ATMEGA168A-AU is well suited to home automation controllers that manage relays, dimmers, and sensor inputs. Its 23 I/O lines directly drive relay driver transistors and read wall-switch and PIR inputs, while the Two-Wire serial interface connects to I2C temperature and humidity sensors. The USART can interface with a wireless module for remote control. The 512 B EEPROM stores scene settings and network addresses across power cycles. The 2.7 V to 5.5 V range allows operation from a 5 V USB supply or a 3.3 V regulator. For controllers needing more memory for scheduling logic or display graphics, the ATMEGA328P-AU is a pin-compatible upgrade.
おすすめ
Portable Instrumentation
Portable instrumentation benefits from the ATMEGA168A-AU's integrated 10-bit ADC, low sleep-mode current, and compact 32-TQFP package. Handheld multimeters, data loggers, and environmental meters use the ADC to digitize sensor signals and the EEPROM to store calibration constants. The 20 MHz core processes readings and drives a character or segment LCD through the I/O ports. Six sleep modes extend battery life between measurements. The 7x7 mm TQFP footprint keeps the PCB small enough for handheld enclosures. The main limitation is the 16 KB flash, which restricts complex display or logging firmware; designs requiring graphics or large data buffers should use the ATMEGA328P-AU.
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: ATMEGA168A-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 | ATMEGA168PA-AU | ATMEGA168-20AU | ATMEGA328P-AU | ATMEGA88PA-AU |
|---|---|---|---|---|---|
| Package | 32-TQFP (7x7 mm) | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same | 32-TQFP (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB | 16 KB | 16 KB | 32 KB | 8 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 2 KB | 512 B |
| EEPROM | 512 B | 512 B | 512 B | 1 KB | 512 B |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| I/O Lines | 23 | 23 | 23 | 23 | 23 |
| Low-Power Technology | Standard low-power | picoPower | Standard low-power | picoPower | picoPower |
主な差別化要因
- A-revision brown-out detection and calibrated internal oscillator （vs ATMEGA168-20AU)
- Standard low-power core with full 20 MHz operation at 2.7 V （vs ATMEGA168PA-AU)
- Half the flash and SRAM of the ATMEGA328P-AU at lower cost （vs ATMEGA328P-AU)
- Double the flash and SRAM of the ATMEGA88PA-AU （vs ATMEGA88PA-AU)
設計ノート
Decouple both VCC and AVCC with 100 nF ceramic capacitors placed as close as possible to the respective pins, and add a 10 uF bulk capacitor near the regulator output. AVCC should be connected through a low-pass filter (10 uH inductor or ferrite bead plus 100 nF) when the ADC is used, per the Microchip ATmega168A datasheet recommendation. Keep the analog ground return separate from the digital ground and join them at a single point to minimize ADC noise.
Place the 16 MHz crystal (if used) within 10 mm of the XTAL1/XTAL2 pins and keep the trace lengths short and symmetric. Route the load capacitors (typically 22 pF) directly to the ground plane. Keep high-speed digital traces away from the crystal and AREF pins to avoid coupling. The 32-TQFP 0.8 mm pitch requires a minimum trace width of 0.15 mm and a solder mask dam between pads for reliable assembly.
The RESET pin (PC6) has an internal pull-up but an external 10 kOhm pull-up plus 100 nF capacitor to ground is recommended for noise immunity in industrial environments. Do not leave AREF floating when using the ADC; connect it to AVCC through a 100 nF capacitor or drive it with an external reference. Estimated: at 5 V and 20 MHz the active current is roughly 10-15 mA, so a 100 mA LDO provides adequate margin for the MCU plus peripherals.
When using the USART at high baud rates, keep the TXD/RXD traces short and avoid routing them parallel to switching regulator nodes. For SPI and I2C buses, add 4.7 kOhm pull-ups on SDA/SCL and keep bus capacitance below 400 pF for reliable 400 kHz operation. Series termination resistors (22-33 Ohm) on long SPI clock lines reduce ringing.
コンプライアンス情報
RoHS and REACH compliance per Microchip product page and distributor listings. The ATmega168A is not AEC-Q100 qualified; automotive designs should use the ATmega168PA automotive-grade variants where available.