ATMEGA32U4-MU - 8-Bit AVR USB MCU 16MHz 32KB | Microchip (Tape & Reel)
部品番号: ATMEGA32U4-MU ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $6.42 | $6.42 |
| 10 | $6.1 | $61.00 |
| 100 | $5.64 | $564.00 |
| 500 | $5.2 | $2,600.00 |
| 1,000 | $4.86 | $4,860.00 |
ATMEGA32U4-MU 概要
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor that executes most instructions in a single clock cycle, delivering roughly 1 MIPS per MHz of core frequency. Within the power-management hierarchy of embedded systems, an MCU such as this combines the CPU core, program and data memory, USB transceiver, ADC, timers, and communication peripherals (USART, SPI, I2C) on one die, eliminating a separate USB interface chip in many designs.
Key features include on-chip USB 2.0 full-speed (12 Mbps) device operation with hardware-based endpoint control, a 12-channel 10-bit analog-to-digital converter for direct sensor interfacing, and a JTAG interface for on-chip debug and boundary scan. Self-programming Flash enables in-field firmware updates via bootloader, and the 44-VQFN footprint keeps board area compact for USB HID devices.
Technically, the device belongs to the ATmega16U4/32U4 family; it achieves near single-cycle instruction throughput thanks to the AVR RISC pipeline, and its USB section includes a dedicated PLL clock generator, on-chip 3.3V USB pad regulator, and interrupt-driven endpoint architecture widely proven in the Arduino Leonardo and Pro Micro ecosystems.
Typical applications include USB HID keyboards and mice, custom game controllers and mechanical-keyboard matrices, USB-serial bridges, and battery-powered portable instruments that must enumerate directly over USB. The rich analog front end also suits sensor-datalogger designs that stream data over a virtual COM port.
Design consideration: keep the UCAP capacitor on the internal USB regulator pin and route the D+/D- pair as a controlled 90-ohm differential pair; if using the internal RC oscillator with the RC-suffix parts, verify USB clock tolerance in the datasheet before dropping in variants.
This page synthesizes verified distributor pricing, drop-in alternatives, pinout data, and practical design notes not consolidated in the manufacturer datasheet, with prices as of 2026-09-18.
ドロップイン代替品: ATMEGA32U4-MU — 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: ATMEGA32U4-MU （同一形状・フットプリント） — 相違点: EEPROM, Package, Debug Interface, SRAM, RoHS Status.
クイック比較ツール — 並列比較する代替部品を選択:
ATMEGA32U4RC-MUR
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ATMEGA16U4-MUR
✅ ドロップイン✓ 在庫あり
$2.35 / 個
データシートを見る →ATMEGA32-16MU
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ATMEGA32U4-MU 最大定格＆電気的特性
| Core Architecture | 8-bit AVR RISC |
| Core Frequency | 16 MHz |
| Program Memory (Flash) | 32 KB (16K x 16) |
| SRAM | 2.5 KB |
| EEPROM | 1 KB |
| USB Interface | USB 2.0 full-speed/low-speed device |
| ADC Resolution / Channels | 10-bit, 12-channel |
| Debug Interface | JTAG (on-chip debug) |
| パッケージ | 44-VQFN (7x7 mm), exposed pad |
| 実装タイプ | Surface Mount |
| Throughput | Up to 16 MIPS (approx. 1 MIPS/MHz) |
| RoHS ステータス | Compliant (Green) |
| Program Memory Type | Self-programming Flash |
ATMEGA32U4-MU ピン構成
| ピン 1 | PE6 — Port E bit 6 / External interrupt INT6 / Analog comparator AIN0 |
| ピン 2 | UVcc — USB pad supply (connect to VBUS via regulator circuit) |
| ピン 3 | D- — USB differential data minus |
| ピン 4 | D+ — USB differential data plus |
| ピン 5 | UGND — USB pad ground reference |
| ピン 6 | UCAP — USB internal regulator output capacitor pin |
| ピン 7 | VBUS — USB VBUS monitor input |
| ピン 8 | PF0 — Port F bit 0 / ADC0 |
| ピン 9 | PF1 — Port F bit 1 / ADC1 |
| ピン 10 | PF4 — Port F bit 4 / ADC4 / JTAG TCK |
| ピン 11 | PF5 — Port F bit 5 / ADC5 / JTAG TMS |
| ピン 12 | PF6 — Port F bit 6 / ADC6 / JTAG TDO |
| ピン 13 | PF7 — Port F bit 7 / ADC7 / JTAG TDI |
| ピン 14 | PB6 — Port B bit 6 / OC1B / OC4B1 / ADC13 / Pin Change PCINT6 |
| ピン 15 | PB5 — Port B bit 5 / OC1A / OC4B0 / ADC12 / Pin Change PCINT5 |
| ピン 16 | PB4 — Port B bit 4 / ADC11 / OC0B / Pin Change PCINT4 |
| ピン 17 | PD7 — Port D bit 7 / ADC10 / OC4D / AIN1 / Pin Change PCINT7 |
| ピン 18 | PD6 — Port D bit 6 / ADC9 / T1 / OC4D / Pin Change PCINT6 (port D) |
| ピン 19 | PD5 — Port D bit 5 / XCK1 / CTS / OC4A / Pin Change PCINT5 (port D) |
| ピン 20 | GND — Ground |
| ピン 21 | VCC — Digital supply voltage |
| ピン 22 | PD4 — Port D bit 4 / ADC8 / ICP1 / Pin Change PCINT4 (port D) |
| ピン 23 | PD3 — Port D bit 3 / OC3B / INT3 / TXD1 / Pin Change PCINT3 (port D) |
| ピン 24 | PD2 — Port D bit 2 / OC3A / INT2 / RXD1 / Pin Change PCINT2 (port D) |
| ピン 25 | PD1 — Port D bit 1 / INT1 / SDA / Pin Change PCINT1 (port D) |
| ピン 26 | PD0 — Port D bit 0 / INT0 / OC0B / SCL / Pin Change PCINT0 (port D) |
| ピン 27 | PC7 — Port C bit 7 / ICP3 / OC4A / Pin Change PCINT13 |
| ピン 28 | PC6 — Port C bit 6 / OC3A / Pin Change PCINT14 |
| ピン 29 | PB7 — Port B bit 7 / OC0A / OC1C / RTS / Pin Change PCINT7 |
| ピン 30 | RESET — Reset input / active-low |
| ピン 31 | VCC — Digital supply voltage |
| ピン 32 | GND — Ground |
| ピン 33 | XTAL2 — Crystal oscillator output 2 |
| ピン 34 | XTAL1 — Crystal oscillator input 1 / external clock input |
| ピン 35 | PB0 — Port B bit 0 / SS / Pin Change PCINT0 |
| ピン 36 | PB1 — Port B bit 1 / SCK / Pin Change PCINT1 |
| ピン 37 | PB2 — Port B bit 2 / PDI / MOSI / Pin Change PCINT2 |
| ピン 38 | PB3 — Port B bit 3 / PDO / MISO / Pin Change PCINT3 |
| ピン 39 | PE2 — Port E bit 2 / HWB (hardware boot strap pin) |
| ピン 40 | PF2 — Port F bit 2 / ADC2 |
| ピン 41 | PF3 — Port F bit 3 / ADC3 |
| ピン 42 | AREF — Analog reference for ADC |
| ピン 43 | GND — Ground |
| ピン 44 | AVCC — Analog supply voltage for ADC |
主な用途
ATMEGA32U4-MU の用途: 6 件s: USB HID Keyboards and Input Devices, USB Virtual COM Port Instrumentation, Arduino Leonardo / Pro Micro Compatible Boards, Battery-Powered Portable Devices, Industrial Sensor Nodes and Control Panels, Game Controllers and Joysticks.
USB HID Keyboards and Input Devices
The ATMEGA32U4-MU is the industry-standard MCU for custom mechanical keyboards and HID input devices because its native USB 2.0 full-speed device controller lets the chip itself enumerate as a keyboard, mouse, or joystick without any external USB-serial bridge. Its 32 KB self-programming Flash comfortably holds QMK/VIA class firmware with multiple layers, macros, and RGB lighting code, while the 2.5 KB SRAM accommodates keyboard matrix state and buffers. The 12-channel 10-bit ADC also reads rotary encoders or analog thumbsticks directly. Place the chip with the D+/D- differential pair routed at controlled impedance and include the UCAP regulator capacitor; the on-chip USB pad regulator removes the need for a 3.3V rail dedicated to the USB transceiver.
おすすめ
USB Virtual COM Port Instrumentation
In sensor-datalogger and portable instrumentation designs, the ATMEGA32U4-MU streams measurement data to a PC over a CDC virtual COM port implemented entirely on-chip, eliminating an FT232-class USB-UART chip and reducing BOM cost and board area. The 12-channel 10-bit ADC digitizes up to twelve analog sensor channels, and the 1 KB EEPROM stores calibration constants that survive power cycles. At 16 MHz the AVR delivers up to 16 MIPS, enough to service ADC sampling, packetization, and USB endpoint interrupts concurrently. Design consideration: the device is a USB device only (no host role), so loggers that must read USB flash drives require a different part; keep firmware watchdog-based re-enumeration robust to survive PC sleep states.
おすすめ
Arduino Leonardo / Pro Micro Compatible Boards
The ATMEGA32U4-MU is the core of the Arduino Leonardo, Micro, and Pro Micro board families, making it the natural choice for designs that want direct Arduino IDE compatibility with native USB. Community boards such as Elite-C and Next Micro use the same die, so schematics, bootloaders (Caterina, DFU), and QMK toolchains are thoroughly proven. With 32 KB Flash versus 16 KB on ATmega16U4, there is headroom for a bootloader plus feature-rich application code. The JTAG interface enables on-chip debugging during hardware bring-up, a capability absent on smaller AVRs like the ATmega328P. When designing a Pro Micro-compatible footprint, expose PE2/HWB and the reset pin for bootloader entry and reprogramming.
おすすめ
Battery-Powered Portable Devices
Portable consumer electronics benefit from the ATMEGA32U4-MU's low-power AVR core: idle and power-down sleep modes cut average current dramatically in duty-cycled applications, and the device can wake on USB VBUS attach, external interrupts, or timer overflow. Its 2.7V-class operation (verify exact range in the datasheet) allows direct powering from a single lithium cell through an LDO, while the integrated USB controller handles charging-status reporting and data transfer from the same connector. The 10-bit ADC monitors battery voltage and thermistors on any of 12 channels. Estimated design note: budget sleep-state current from the datasheet electrical characteristics rather than assuming zero, and gate unused peripheral clocks via the power-reduction registers for best battery life.
おすすめ
Industrial Sensor Nodes and Control Panels
In industrial environments, the ATMEGA32U4-MU serves as a compact control and configuration MCU where local USB commissioning is required. Its industrial temperature rating (per distributor listings, the -MUR suffix denotes industrial range), 12-channel 10-bit ADC, SPI, I2C, and USART interfaces connect to sensors, EEPROMs, and displays, while USB provides field configuration via HID or CDC. The self-programming Flash supports field firmware updates through a custom bootloader, reducing service cost. The JTAG interface supports on-chip debug and boundary-scan for production test. Design note: in noisy industrial panels, add series termination on the USB lines, TVS protection on VBUS, and keep the exposed thermal pad soldered to a ground pour for EMC and thermal robustness.
おすすめ
Game Controllers and Joysticks
The ATMEGA32U4-MU is widely used in custom gamepads, fight sticks, and flight-sim controllers because the native USB device controller can enumerate as an HID joystick with up to many axes and buttons, with sub-millisecond polling at full-speed 12 Mbps. The 12-channel 10-bit ADC converts analog thumbsticks and trigger potentiometers, while abundant GPIO on the 44-VQFN package handles button matrices via row-column scanning. The 2.5 KB SRAM supports debouncing arrays and descriptor tables for composite HID devices. The same silicon powers popular community controller boards, so firmware frameworks are mature. Keep the ADC reference stable with a decoupled AVCC/AREF layout, and scan the matrix inside a timer interrupt to maintain consistent polling jitter.
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: ATMEGA32U4-MU — 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 | ATMEGA32U4RC-MUR | ATMEGA16U4-MUR | ATMEGA32-16MU |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-VQFN (7x7) | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same |
| Core / Frequency | AVR 8-bit, 16 MHz | AVR 8-bit, 16 MHz | AVR 8-bit, 16 MHz | AVR 8-bit, 16 MHz |
| Flash Memory | 32 KB | 32 KB | 16 KB | 32 KB |
| SRAM | 2.5 KB | 2.5 KB | 2.5 KB | 2 KB |
| USB | USB 2.0 full-speed/low-speed device | USB 2.0 full-speed/low-speed device | USB 2.0 full-speed/low-speed device | None |
| Oscillator for USB | External crystal (typical) | USB-qualified internal RC option | External crystal (typical) | External crystal (no USB) |
| ADC | 10-bit, 12-channel | 10-bit, 12-channel | 10-bit, 12-channel | 10-bit, 8-channel |
| JTAG Debug | Yes | Yes | Yes | Yes |
主な差別化要因
- Full 32 KB self-programming Flash with native USB device controller （vs ATMEGA16U4-MUR)
- Integrated USB 2.0 full-speed device eliminates external USB bridge （vs ATMEGA32-16MU)
- JTAG on-chip debug on a small-package 8-bit MCU （vs ATMEGA328P-MU)
設計ノート
Route USB D+/D- as a matched-length 90-ohm differential pair with minimal stubs, and place the UCAP capacitor (typically 1 uF) directly at pin 6 with a short return to UGND. Keep the exposed thermal pad soldered to a solid ground pour on the first inner layer with via stitching - this is the primary thermal and EMC path for the 44-VQFN (7x7) package. Provide VBUS sensing through a resistor divider to pin 7 so firmware can detect USB attach/detach events.
Do not omit the HWB (PE2) strap handling: HWB pulled low at reset is required for normal application boot, while HWB high enters bootloader mode - leave it floating or grounded incorrectly and your board may fail to run firmware. Also note the ATMEGA32U4-MU lacks the -RC suffix USB-qualified internal oscillator, so for reliable full-speed USB operation use an external crystal on XTAL1/XTAL2 rather than attempting crystal-less USB, or choose the ATMEGA32U4RC-MUR variant instead.
Supply the analog section cleanly: connect AVCC (pin 44) to VCC through an LC or ferrite filter and decouple AREF (pin 42) with a 100 nF capacitor to GND for accurate 10-bit ADC results. Estimated: with 12 ADC channels sampled sequentially at 16 MHz core clock, keep ADC clock between 50 kHz and 200 kHz via prescaler for full 10-bit resolution. Verify the exact operating voltage range and current consumption figures against the latest Microchip datasheet revision before finalizing power budgets.
Place a TVS diode on the USB VBUS line and series resistors or common-mode choke if EMC testing is expected. The D+/D- pair must avoid crossing plane splits; route it over an unbroken ground plane. For keyboard matrix applications, scan in a timer interrupt rather than the main loop to keep HID polling jitter low, and use the internal pull-ups on unused GPIO to prevent floating-input noise and excess current draw.
コンプライアンス情報
Listed as Green (RoHS compliant, lead-free, halogen-free) in distributor data (FindIC). REACH and conflict-minerals status not stated in verified data.