ATMEGA48PA-PU - 8-bit AVR MCU 4KB Flash 20MHz DIP-28 | Microchip
MPN: ATMEGA48PA-PU ✓ Hoạt độngATMEGA48PA-PU Tóm tắt
An 8-bit microcontroller is a single-chip computer whose CPU processes data 8 bits at a time. The AVR family sits within the broader microcontroller hierarchy: microcontroller unit (MCU) -> embedded processor -> integrated circuit. AVR MCUs use a Harvard architecture with separate program and data buses, allowing most of the 131 instructions to execute in a single clock cycle, which yields up to 20 MIPS throughput at 20 MHz.
Key features of the ATMEGA48PA include the picoPower technology for ultra-low sleep-mode currents, 23 general-purpose I/O lines, three flexible timer/counters with compare modes, a 10-bit ADC with 8 channels, a USART, an SPI interface, and a two-wire (I2C-compatible) serial interface. The device operates from 2.5V to 5.5V, supporting both 3.3V and 5V systems, and offers six software-selectable power-saving modes including Power-down at very low current.
Architecturally, the ATMEGA48PA pairs the AVR enhanced RISC core with 32 general-purpose working registers, all directly connected to the ALU, enabling single-cycle access that eliminates the accumulator bottleneck of conventional 8051-style cores. The picoPower AVRs are fabricated on a low-leakage process, and the PA suffix denotes the power-optimized variant of the ATmega48 family.
Typical applications include hobbyist and educational projects (Arduino-compatible breadboard designs), appliance control, simple industrial sensing nodes, LED lighting controllers, and low-cost embedded systems where through-hole soldering and easy prototyping in DIP form matter.
A key design consideration: at 5V the device can run at the full 20 MHz, but at 3.3V the maximum safe clock is approximately 13.3 MHz per the datasheet frequency-versus-voltage curve; plan a 16 MHz or 8 MHz crystal for 3V operation.
This page synthesizes distributor pricing, drop-in family alternatives (ATmega88PA/168PA/328P-PU share the same DIP-28 footprint), and practical design notes not found in a single manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho ATMEGA48PA-PU — 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 ATMEGA48PA-PU (cùng hình factor và footprint) — khác nhau ở Operating Temperature, Package, Timers, Communication Interfaces, SRAM.
ATMEGA48A-PU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA88PA-PU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA168PA-PU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA328P-PU
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA48-20PI
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ATMEGA48PA-PU Tỷ lệ tối đa & tính chất điện
| Core Architecture | AVR 8-bit RISC |
| Flash Program Memory | 4 KB (2K x 16) |
| EEPROM | 256 B |
| SRAM | 512 B |
| Tần số xung maksimum | 20 MHz |
| Max MIPS Throughput | 20 MIPS at 20 MHz |
| Supply Voltage Range | 2.5 V to 5.5 V |
| General Purpose I/O | 23 lines |
| Timers | Two 8-bit + one 16-bit timer/counter |
| ADC | 10-bit, 8 channels |
| Serial Interfaces | USART, SPI, 2-wire (I2C-compatible) |
| Nhiệt độ hoạt động | -40C to +85C (industrial) |
| Hộp | 28-PDIP |
| Kiểu lắp đặt | Through Hole |
| Programming Method | In-System Programmable (ISP) |
| Trạng thái RoHS | Compliant |
| Instructions | 131 instructions, most single-cycle |
Cấu hình chân ATMEGA48PA-PU
| Chân 1 | PC6/RESET — Reset input or Port C bit 6 |
| Chân 2 | PD0/RXD — USART receive or Port D bit 0 |
| Chân 3 | PD1/TXD — USART transmit or Port D bit 1 |
| Chân 4 | PD2/INT0 — External interrupt 0 or Port D bit 2 |
| Chân 5 | PD3/INT1/OC2B — External interrupt 1 / Timer2 PWM or Port D bit 3 |
| Chân 6 | PD4/T0/XCK — Timer0 clock / USART external clock or Port D bit 4 |
| Chân 7 | VCC — Digital supply voltage (2.5V to 5.5V) |
| Chân 8 | GND — Ground |
| Chân 9 | PB6/XTAL1/TOSC1 — Crystal oscillator input or Port B bit 6 |
| Chân 10 | PB7/XTAL2/TOSC2 — Crystal oscillator output or Port B bit 7 |
| Chân 11 | PD5/T1/OC0B — Timer1 clock / Timer0 PWM or Port D bit 5 |
| Chân 12 | PD6/AIN0/OC0A — Analog comparator positive input / Timer0 PWM or Port D bit 6 |
| Chân 13 | PD7/AIN1/OC1A — Analog comparator negative input / Timer1 PWM or Port D bit 7 |
| Chân 14 | PB0/ICP1/CLKO — Timer1 input capture / clock output or Port B bit 0 |
| Chân 15 | PB1/OC1A — Timer1 PWM output or Port B bit 1 |
| Chân 16 | PB2/SS/OC1B — SPI slave select / Timer1 PWM or Port B bit 2 |
| Chân 17 | PB3/MOSI/OC2A — SPI Master Out Slave In / Timer2 PWM or Port B bit 3 |
| Chân 18 | PB4/MISO — SPI Master In Slave Out or Port B bit 4 |
| Chân 19 | PB5/SCK — SPI serial clock or Port B bit 5 |
| Chân 20 | AVCC — ADC supply voltage (connect to VCC through low-pass filter) |
| Chân 21 | AREF — ADC analog reference input (decouple to GND) |
| Chân 22 | GND — Ground |
| Chân 23 | PC0/ADC0 — ADC channel 0 or Port C bit 0 |
| Chân 24 | PC1/ADC1 — ADC channel 1 or Port C bit 1 |
| Chân 25 | PC2/ADC2 — ADC channel 2 or Port C bit 2 |
| Chân 26 | PC3/ADC3 — ADC channel 3 or Port C bit 3 |
| Chân 27 | PC4/ADC4/SDA — ADC channel 4 / two-wire data or Port C bit 4 |
| Chân 28 | PC5/ADC5/SCL — ADC channel 5 / two-wire clock or Port C bit 5 |
Ứng dụng tiêu biểu
ATMEGA48PA-PU phù hợp cho 6 Áp dụngs: Hobbyist and Educational Prototyping, Battery-Powered Sensor Nodes, Appliance and White-Goods Control, LED Lighting Controllers, Industrial Sensor Interfacing and Data Logging, Simple Embedded Communication Nodes.
Hobbyist and Educational Prototyping
The ATMEGA48PA-PU is a staple of breadboard electronics education because its 0.1-inch PDIP package plugs directly into solderless breadboards without adapters. Its 4 KB Flash is sufficient for classic exercises such as LED sequencing, button debouncing, PWM motor control, and serial telemetry, while the 20 MHz clock and single-cycle RISC execution give students responsive, predictable timing. Programming requires only a low-cost USBasp ISP programmer connected to the SPI header (MOSI/MISO/SCK on pins 17-19). The same footprint accepts ATMEGA88PA-PU or ATMEGA328P-PU upgrades, so a learning board scales with skill level without redesign.
Được đề xuất
Battery-Powered Sensor Nodes
The picoPower ATMEGA48PA excels in battery-operated sensing where sleep current dominates battery life. In Power-down mode with watchdog running, supply current is in the microamp range per the Microchip datasheet, letting a coin-cell node idle for years between periodic ADC samples. The 10-bit, 8-channel ADC reads temperature, humidity, or light sensors directly, and the two-wire interface talks to I2C sensors at 100-400 kHz. Designers should drive I/O pins to defined levels before sleeping (avoid floating inputs) and select the 2.7V brown-out threshold for 3V coin-cell rails. A 3.3V/8 MHz crystal configuration keeps operation safely inside the frequency-voltage envelope.
Được đề xuất
Appliance and White-Goods Control
Low-cost appliance control panels - fan speed, temperature cut-offs, indicator LEDs, and membrane-key handling - map naturally onto the ATMEGA48PA-PU's 23 GPIO lines and three timer/counters. The 16-bit timer supports phase-correct PWM for triac or relay phase control, while the internal 8 MHz RC oscillator eliminates crystal cost in non-critical timing applications. The 4 KB Flash holds a full state-machine application with serial diagnostics via the USART. Its industrial -40C to +85C rating covers unventilated appliance interiors, and the DIP package simplifies field-repairable designs or low-volume through-hole assembly in service markets.
Được đề xuất
LED Lighting Controllers
Dimming and color-mixing LED fixtures benefit from the ATMEGA48PA-PU's hardware PWM: the two 8-bit timers each provide two compare channels and the 16-bit timer adds high-resolution dimming up to roughly 16-bit effective resolution with dithering. Driving MOSFET gate drivers from PB0-PB5 keeps switching losses predictable, and the 5V DIP device tolerates noisy lighting environments better than 3.3V-only MCUs. The ADC monitors supply voltage and LED thermal feedback through an NTC channel, enabling thermal fold-back firmware. At 20 MHz, a 300 Hz PWM carrier with 8-bit resolution and serial DMX-like control protocols fits comfortably in 4 KB.
Được đề xuất
Industrial Sensor Interfacing and Data Logging
The ATMEGA48PA-PU serves as a low-cost front-end converting analog transducer signals into digital data. Its 10-bit ADC with differential inputs and 1x/20x gain stages measures thermocouple-amplified or bridge signals, while the USART streams readings to a host at up to 115.2 kbps (at 20 MHz). The 256 B EEPROM stores calibration constants that survive power cycles, and the watchdog timer provides autonomous recovery in unmanned installations. For higher-channel-count or 24-bit precision requirements, pair it with external ADCs over SPI. Designers should route AVCC (pin 20) separately through an LC filter and tie AREF to a decoupled reference for best noise performance.
Được đề xuất
Simple Embedded Communication Nodes
The built-in USART plus SPI and two-wire interfaces make the ATMEGA48PA-PU a practical protocol converter: RS-485 field devices to I2C sensors, SPI EEPROM expansion, or software-UART debug bridges. The 20 MHz clock divides cleanly for standard baud rates (up to 1 Mbps USART in double-speed mode per the datasheet), and pin-change interrupts on all 23 GPIO lines allow bit-banged protocols such as 1-Wire or DHT sensor timing. At 5V, logic levels interface directly with classic RS-485 transceivers. Firmware overhead for framing, CRC, and buffering typically stays under 2 KB, leaving comfortable margin in the 4 KB Flash.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ATMEGA48PA-PU — 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 | ATMEGA48A-PU | ATMEGA88PA-PU | ATMEGA168PA-PU | ATMEGA328P-PU | ATMEGA48-20PI |
|---|---|---|---|---|---|---|
| Package | 28-PDIP | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same | 28-PDIP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 4 KB | 4 KB | 8 KB | 16 KB | 32 KB | 4 KB |
| SRAM | 512 B | 512 B | 1 KB | 1 KB | 2 KB | 512 B |
| EEPROM | 256 B | 256 B | 512 B | 512 B | 1 KB | 256 B |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage Range | 2.5 V to 5.5 V | 2.7 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 1.8 V to 5.5 V | 4.5 V to 5.5 V |
| Low Power (picoPower) | Yes (PA variant) | No (standard power) | Yes (PA variant) | Yes (PA variant) | Yes (P variant) | No (older generation) |
| Pin Compatibility | 28-pin mega48/88/168/328 DIP footprint | Pin-to-pin compatible | Pin-to-pin compatible | Pin-to-pin compatible | Pin-to-pin compatible | Pin-to-pin compatible |
Bảo phân biệt quan trọng
- picoPower sleep currents in through-hole DIP (vsATMEGA48A-PU)
- Lowest cost within a scalable pin-compatible family (vsATMEGA328P-PU)
- Wider low-voltage operation than the older ATmega48 (vsATMEGA48-20PI)
Ghi chú thiết kế
Respect the frequency-versus-voltage curve: 20 MHz is safe only at 4.5-5.5V. At 3.3V, limit the clock to roughly 13.3 MHz per the Microchip datasheet; use a 16 MHz crystal only if you accept marginal timing or run at 5V. Connect AVCC (pin 20) to VCC through an LC filter (10 uH + 100 nF) even if the ADC is unused - the datasheet requires AVCC within 0.3V of VCC. Set the brown-out detector via fuses (4.3V for 5V rails, 2.7V for 3.3V) so EEPROM writes are never corrupted during brown-out.
Even in through-hole designs, keep a 100 nF ceramic decoupling capacitor within a few millimeters of VCC (pin 7) and another at AVCC (pin 20). Decouple AREF (pin 21) with 100 nF to GND and never use it as a general power output unless the REFS bits select external reference mode deliberately. The DIP-28 lead inductance is modest, but long breadboard wires on the ISP header (pins 17-19) commonly cause SPI programming failures above 1 MHz SCK - slow the programmer clock if programming is unreliable.
Default fuse settings run the device from the internal 8 MHz RC oscillator divided by 8 (1 MHz), which surprises engineers expecting 20 MHz - set CKOUT/CKSEL fuses for your crystal and disable CKDIV8. Pin 1 (RESET) must be held high via a 10k pull-up; enabling RSTDISBL disables ISP programming. If migrating to ATmega48PB as Microchip's drop-in replacement, note the datasheet cautions: pin 3 must not be actively driven when tied to GND, and pin 6 must not be actively driven when tied to VCC.
Estimated: worst-case dissipation is negligible for this MCU. At 5.5V with a typical active-mode current on the order of 0.2-0.3 mA per MHz (about 5-6 mA at 20 MHz, per datasheet family curves), power is roughly 30 mW - no heatsink or copper pour consideration applies. Thermal design effort should instead go to adjacent power components (regulators, LED drivers). This estimate uses datasheet family typical-current figures; verify against the electrical characteristics table for your exact clock and voltage configuration.
Thông tin tuân thủ
RoHS compliance and lead-free construction per Microchip current-production packaging for ATmega48PA. REACH, halogen-free, and conflict-minerals declarations should be pulled from Microchip's official compliance certificate for the exact date code.
