ATMEGA48-20AU - 8-bit AVR MCU 20MHz 4KB Flash | Microchip
MPN: ATMEGA48-20AU ✓ Hoạt độngATMEGA48-20AU Tóm tắt
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and configurable peripherals on one piece of silicon. The ATmega48 belongs to the 8-bit AVR family of microcontrollers, a subcategory of embedded controllers within the broader semiconductor hierarchy that bridges simple timers and complex MPU-based systems. By executing powerful instructions in a single clock cycle, AVR cores achieve throughput approaching 1 MIPS per MHz, giving designers a favorable performance-per-watt trade-off for cost-sensitive embedded products.
Key features include 130 instructions (mostly single-cycle), 32 general-purpose working registers, fully static operation, six sleep modes (idle, ADC noise reduction, power-save, power-down, standby, extended standby), on-chip debug via debugWIRE, and a programmable watchdog timer with on-chip oscillator. The 6-channel 10-bit successive-approximation ADC provides 8 or 10 selectable resolutions and supports free-running or single-conversion modes. The internal calibrated RC oscillator and external crystal options simplify BOM cost.
The TQFP-32 (7x7 mm, 0.8 mm pitch) package supports industrial 5V designs and is footprint-compatible with the wider ATmega48/88/168 family, allowing engineers to migrate upward to larger Flash sizes (8 KB / 16 KB) on the same PCB. In-system programming via SPI permits firmware updates on the finished PCB, while the boot loader support enables self-programming.
Typical applications include industrial control panels, home appliance controllers, sensor data-acquisition nodes, low-cost motor drivers, USB-to-UART bridges, and hobbyist or educational embedded platforms built around the mature AVR GCC toolchain and Arduino-compatible cores such as MiniCore. When designing with this part, note that unlike the picoPower ATMEGA48PA variants (1.8V-5.5V operation), this classic 20 MHz version targets 5V systems; for battery designs below 4.5V, choose the ATMEGA48PA instead.
This page synthesizes distributor pricing, drop-in same-footprint alternatives across the ATmega48/88/168/328 family, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho ATMEGA48-20AU — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với ATMEGA48-20AU (cùng hình factor và footprint) — khác nhau ở Package, RoHS Status, ADC, Operating Temperature, Communication Interfaces.
ATMEGA48PA-AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA88-20AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA168-20AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA164A-AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA328P-AUR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA324PV-10AU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA48-20AU Tỷ lệ tối đa & tính chất điện
| Core Architecture | 8-bit AVR RISC (enhanced) |
| Program Memory (Flash) | 4 KB (2K x 16) |
| EEPROM | 256 B |
| SRAM | 512 B |
| Maximum CPU Frequency | 20 MHz |
| Throughput | Up to 20 MIPS |
| Supply Voltage (Vcc) | 4.5 V to 5.5 V |
| I/O Pins | 23 |
| ADC | 6-channel, 10-bit |
| Timer/Counters | 3 (2x 8-bit, 1x 16-bit) |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| Hộp | 32-pin TQFP (7x7 mm, 0.8 mm pitch) |
| Nhiệt độ hoạt động | -40C to +85C (industrial) |
| On-chip Debug | debugWIRE |
| In-System Programming | Yes (SPI) |
| Sleep Modes | 6 (Idle, ADC NR, Power-save, Power-down, Standby, Ext Standby) |
| Watchdog Timer | Programmable, with on-chip oscillator |
| Trạng thái RoHS | Compliant |
Cấu hình chân ATMEGA48-20AU
| Chân 1 | PD3 (OC2B/INT1) — Port D bit 3, Timer/Counter2 Output Compare B, External Interrupt 1 |
| Chân 2 | PD4 (T0) — Port D bit 4, Timer/Counter0 Clock Input |
| Chân 3 | GND — Ground |
| Chân 4 | VCC — Supply voltage |
| Chân 5 | GND — Ground |
| Chân 6 | VCC — Supply voltage |
| Chân 7 | PB6 (XTAL1/TOSC1) — Port B bit 6, Crystal oscillator pin 1, Timer Oscillator pin 1 |
| Chân 8 | PB7 (XTAL2/TOSC2) — Port B bit 7, Crystal oscillator pin 2, Timer Oscillator pin 2 |
| Chân 9 | PD5 (OC0B/T1) — Port D bit 5, Timer/Counter0 Output Compare B, Timer/Counter1 Clock Input |
| Chân 10 | PD6 (OC0A/AIN0) — Port D bit 6, Timer/Counter0 Output Compare A, Analog Comparator Positive Input |
| Chân 11 | PD7 (AIN1) — Port D bit 7, Analog Comparator Negative Input |
| Chân 12 | PB0 (ICP1) — Port B bit 0, Timer/Counter1 Input Capture Pin |
| Chân 13 | PB1 (OC1A) — Port B bit 1, Timer/Counter1 Output Compare A |
| Chân 14 | PB2 (OC1B/SS) — Port B bit 2, Timer/Counter1 Output Compare B, SPI Slave Select |
| Chân 15 | PB3 (MOSI/OC2A) — Port B bit 3, SPI MOSI, Timer/Counter2 Output Compare A |
| Chân 16 | PB4 (MISO) — Port B bit 4, SPI MISO |
| Chân 17 | PB5 (SCK) — Port B bit 5, SPI Clock |
| Chân 18 | AVCC — Analog supply voltage for ADC |
| Chân 19 | ADC6 — Analog input channel 6 (TQFP package only) |
| Chân 20 | AREF — ADC reference voltage |
| Chân 21 | GND — Ground |
| Chân 22 | ADC7 — Analog input channel 7 (TQFP package only) |
| Chân 23 | PC0 (ADC0) — Port C bit 0, Analog input channel 0 |
| Chân 24 | PC1 (ADC1) — Port C bit 1, Analog input channel 1 |
| Chân 25 | PC2 (ADC2) — Port C bit 2, Analog input channel 2 |
| Chân 26 | PC3 (ADC3) — Port C bit 3, Analog input channel 3 |
| Chân 27 | PC4 (ADC4/SDA) — Port C bit 4, Analog input channel 4, TWI Data |
| Chân 28 | PC5 (ADC5/SCL) — Port C bit 5, Analog input channel 5, TWI Clock |
| Chân 29 | PC6 (RESET) — Port C bit 6, Reset pin (active low) |
| Chân 30 | PD0 (RXD) — Port D bit 0, USART Receive |
| Chân 31 | PD1 (TXD) — Port D bit 1, USART Transmit |
| Chân 32 | PD2 (INT0) — Port D bit 2, External Interrupt 0 |
Ứng dụng tiêu biểu
ATMEGA48-20AU phù hợp cho 7 Áp dụngs: Industrial Control Panels, Home Appliance Controllers, Sensor Data Acquisition Nodes, USB-to-UART Bridge, Hobbyist and Educational Embedded Platforms, Low-Cost Motor Control, LED Lighting and Signage Controllers.
Industrial Control Panels
The ATMEGA48-20AU is well suited for industrial control panels requiring a reliable 5V 8-bit controller with deterministic response times. Its 20 MIPS throughput at 20 MHz, 23 GPIO pins, and three timer/counters with PWM outputs allow direct interface to keypads, character LCDs, relay drivers, and optocoupler-isolated inputs. The industrial -40C to +85C operating range covers most factory-floor enclosures, and the ATmega instruction set is well documented for IEC 61508 SIL-2 designs using supplemental watchdog and brown-out supervision. For cost-sensitive PLC expansion I/O modules where 4 KB Flash is sufficient for ladder-logic-style firmware, the ATMEGA48-20AU offers a lower BOM than ATMEGA328P variants.
Được đề xuất
Home Appliance Controllers
Washing machines, dishwashers, microwave ovens, and air-conditioner control boards traditionally use 8-bit MCUs for their main user-interface logic. The ATMEGA48-20AU provides 4 KB Flash for state-machine firmware, 23 GPIO for seven-segment displays and key matrices, and the 10-bit ADC for sensor inputs such as NTC thermistors and water-level probes. Its hardware USART enables simple diagnostic interfaces with factory test equipment, while the hardware TWI port can drive EEPROM for user-setting storage alongside the internal 256-byte EEPROM. The 5V operation matches legacy appliance power rails, avoiding level shifters that complicate UL/IEC 60730 safety designs.
Được đề xuất
Sensor Data Acquisition Nodes
Low-cost wireless or wired sensor nodes benefit from the ATMEGA48-20AU's 6-channel 10-bit ADC, 512-byte SRAM, and 6 sleep modes that drop current consumption into the microamp range between conversions. In a typical 4-20 mA loop-powered or battery-powered sensor transmitter, the MCU wakes on timer or external interrupt, reads one or more ADC channels, applies linearization in firmware, and transmits the result over UART or TWI. The 23 GPIO can multiplex SPI sensors, UART modbus interfaces, and digital I/O expanders on the same board, while the hardware TWI port simplifies interfacing to external temperature, humidity, or pressure sensors.
Được đề xuất
USB-to-UART Bridge
Although the ATMEGA48-20AU lacks native USB hardware, its on-chip USART plus a low-cost USB-to-serial converter IC creates a robust CDC-class bridge for legacy RS-232 equipment migration. Firmware in 4 KB Flash implements baud-rate auto-detection, hardware and software flow control, and command-line diagnostics. The 20 MHz CPU ensures timing-accurate serial handling at up to 115200 baud without bit-banging. For designs requiring actual USB device functionality (HID, CDC, MIDI), upgrade to the ATMEGA32U4-AU which integrates USB 2.0 full-speed hardware in a similar TQFP package footprint.
Được đề xuất
Hobbyist and Educational Embedded Platforms
The ATMEGA48-20AU is a popular teaching platform for AVR assembly and embedded C courses because of its mature toolchain (AVR GCC, Microchip Studio) and Arduino-compatible cores such as MiniCore. With 4 KB Flash, students can fit simple blink, UART-echo, ADC-reading, and PWM-control labs without paying for ATmega328P BOM cost. The 23 GPIO mapped through Arduino digital/analog pin numbers let students reuse Arduino shields designed for the ATmega328P Uno form factor with minor pin remapping. The debugWIRE on-chip debug interface and Atmel-ICE programmer provide single-wire debugging - a major teaching advantage over pure simulation.
Được đề xuất
Low-Cost Motor Control
For simple brushed DC, stepper, or low-frequency BLDC commutation tasks, the ATMEGA48-20AU provides three timer/counters with complementary PWM outputs suitable for H-bridge gate drivers. Its 20 MIPS throughput handles trapezoidal commutation for small sensorless BLDC fans or pumps, and the 6-channel ADC samples back-EMF or current-sense amplifiers with 10-bit resolution. The 23 GPIO provides dedicated lines for Hall sensors, fault inputs, and direction/enable control. For high-speed field-oriented control (FOC) above 50 kHz PWM, choose the ATMEGA328P-AUR or migrate to an ARM Cortex-M0 MCU such as the ATSAMD21 family.
Được đề xuất
LED Lighting and Signage Controllers
Addressable LED strips (WS2812B, APA102) and character-matrix signs can be driven by the ATMEGA48-20AU using bit-banged or SPI peripherals. The 20 MHz clock supports tight timing loops for WS2812B reset codes at 800 kbps with margin, while the SPI peripheral can drive APA102 strips at multi-MHz rates. The 23 GPIO can be reassigned at runtime to drive multiple LED panels, keypads, and DMX-512 interfaces over UART. The internal EEPROM stores user-configurable patterns and brightness curves, and the 4 KB Flash comfortably fits WS2812B library, color-correction LUTs, and effect engines for hundreds of pattern combinations.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ATMEGA48-20AU — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | ATMEGA48PA-AU | ATMEGA88-20AU | ATMEGA168-20AU | ATMEGA164A-AU | ATMEGA328P-AUR |
|---|---|---|---|---|---|---|
| Package | TQFP-32 (7x7 mm) | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same | TQFP-32 (7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 4 KB | 4 KB | 8 KB | 16 KB | 16 KB | 32 KB |
| SRAM | 512 B | 512 B | 1 KB | 1 KB | 1 KB | 2 KB |
| EEPROM | 256 B | 256 B | 512 B | 512 B | 512 B | 1 KB |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage Range | 4.5V to 5.5V | 1.8V to 5.5V | 4.5V to 5.5V | 4.5V to 5.5V | 1.8V to 5.5V | 1.8V to 5.5V |
| I/O Pins | 23 | 23 | 23 | 23 | 32 | 23 |
| ADC Channels | 6 (10-bit) | 6 (10-bit) | 6 (10-bit) | 6 (10-bit) | 8 (10-bit) | 8 (10-bit) |
Bảo phân biệt quan trọng
- Smallest Flash in the ATmega48/88/168/328 family - lowest BOM cost (vsATMEGA328P-AUR)
- Classic 5V-only variant with broad ecosystem support (vsATMEGA48PA-AU)
- Pin-compatible with larger Flash siblings for code-size migration (vsATMEGA88-20AU and ATMEGA168-20AU)
Ghi chú thiết kế
Decouple both VCC pins (pins 4 and 6) and the AVCC pin (pin 18) with 100 nF ceramic capacitors placed within 5 mm of each pin, and add a 10 uF bulk capacitor at the MCU side. AVCC must be tied to VCC through an LC filter (10 ohm + 100 nF) when the ADC is used to suppress digital switching noise coupling into the analog supply. The AREF pin should be bypassed with a 100 nF capacitor when using internal ADC reference, or driven from a low-impedance external reference when ADC accuracy matters.
Route the XTAL1/XTAL2 traces (pins 7 and 8) as short as possible, keep them away from high-frequency digital lines such as clock and PWM outputs, and place the load capacitors (typically 12-22 pF for a 20 MHz crystal) within 3 mm of the XTAL pins with a ground guard ring. The RESET pin (PC6, pin 29) requires a 10 kohm pull-up to VCC and a 100 nF decoupling capacitor adjacent to the pin to support in-system programming reliably.
Do not assume the ATmega48 boot loader section is identical to ATmega88/168 - the lock bits and boot size configuration differ; always recompile or change fuses when migrating. The 'PB6/PB7' crystal pins cannot be used as GPIO when the external oscillator is enabled. ISP programming via SPI uses PB3/MOSI, PB4/MISO, PB5/SCK plus RESET - leave these four pins accessible (test pad, header, or programming connector) on the production PCB for firmware updates. The 4 KB Flash limits string-heavy applications - use PROGMEM and F() macros to keep SRAM free.
Estimated: at 20 MHz, 5V, and full GPIO toggle, the ATMEGA48-20AU consumes roughly 15-20 mA of active current. With the TQFP-32 package's theta_JA of approximately 50 C/W (typical 4-layer JEDEC EIA/JESD51 board), the junction-to-ambient temperature rise is about 1 C above ambient - well within the -40C to +85C industrial range. No special thermal management is required for normal embedded use; only high-ambient (>70C) enclosures with sealed housings may benefit from thermal vias under the exposed pad region if present in the PCB layout.
Thông tin tuân thủ
RoHS and REACH compliant per Microchip product page. Industrial temperature grade -40C to +85C. Not AEC-Q100 qualified - choose ATmega48 variants with automotive grade for vehicle applications.
