ATMEGA32A-PU - 16MHz 8-bit AVR MCU, 32KB Flash, PDIP-40
MPN: ATMEGA32A-PU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.1 | $6.10 |
| 10 | $5.55 | $55.50 |
| 100 | $4.92 | $492.00 |
| 500 | $4.4 | $2,200.00 |
| 1,000 | $3.85 | $3,850.00 |
ATMEGA32A-PU Overview
What is an AVR 8-bit microcontroller? An AVR is a modified Harvard RISC architecture developed by Atmel (now Microchip) that fetches one 16/32-bit instruction per clock cycle, executes most instructions in a single cycle, and pairs the core with tightly coupled Flash, SRAM and EEPROM. In the broader taxonomy, the ATmega32A sits at: 8-bit MCU -> microcontroller -> embedded processor -> semiconductor. It belongs to the mid-range megaAVR family, positioned between the 8-pin ATtiny series and the high-pin-count ATmega2560/ATmega4809 devices.
Key features of the ATMEGA32A-PU include a hardware multiplier, true read-while-write self-programming Flash, an internal calibrated RC oscillator, a programmable watchdog timer with separate on-chip oscillator, and a JTAG/OCD interface compliant with IEEE 1149.1. The brown-out detector (BOD) and power-on reset (POR) provide robust supply supervision for industrial environments.
The architecture uses a two-stage pipelined ALU with 32 general-purpose working registers directly connected to the arithmetic logic unit, eliminating the accumulator bottleneck common to older 8051 designs. This delivers deterministic single-cycle throughput on the 131-instruction set, enabling efficient DSP and control loops without resorting to a 16/32-bit core.
Typical applications include Arduino-compatible prototyping boards, industrial automation controllers, sensor hubs, motor control, smart energy meters, and consumer white goods. The wide 4.5V-5.5V supply range and on-chip peripherals make it suitable for both mains-powered and battery-tolerant systems when paired with a 3.3V LDO.
When designing with this device, decouple VCC and AVCC with 100nF ceramic capacitors placed within 5mm of each supply pin, and route analog/digital grounds as a star back to the GND pin to minimize ADC noise. The 40-pin PDIP footprint is breadboard-friendly, simplifying prototyping and field replacement.
Drop-in alternatives for ATMEGA32A-PU β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATMEGA32A-PU (same form factor and footprint) β differing in Package, Debug Interface, Operating Temperature, EEPROM, SRAM.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA32-16PU
β Drop-Inβ In Stock
$3.68 / Unit
View Datasheet βATMEGA32A-PN
β Drop-Inβ In Stock
$4.15 / Unit
View Datasheet βATMEGA644A-PU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA324A-PU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA32A-PU Maximum Ratings & Electrical Characteristics
| Architecture | AVR 8-bit RISC (modified Harvard) |
| Program Memory (Flash) | 32 KB (16K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Maximum Clock Frequency | 16 MHz |
| Instruction Throughput | 16 MIPS at 16 MHz |
| Supply Voltage (Vcc) | 4.5 V to 5.5 V |
| I/O Pins | 32 programmable |
| ADC | 8-channel, 10-bit |
| Timers/Counters | Two 8-bit, one 16-bit |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| Debug Interface | JTAG (IEEE 1149.1) |
| Operating Temperature | -40 C to +85 C (industrial) |
| Package | 40-pin PDIP (PU) |
| Mounting Type | Through-Hole |
| RoHS Status | Compliant |
ATMEGA32A-PU Pin Configuration
| Pin 1 | PB0 (XCK/T0) β Port B bit 0 / XCK / Timer0 clock input |
| Pin 2 | PB1 (T1) β Port B bit 1 / Timer1 external clock |
| Pin 3 | PB2 (AIN0/INT2) β Port B bit 2 / analog comparator pos / INT2 |
| Pin 4 | PB3 (AIN1/OC0) β Port B bit 3 / analog comparator neg / OC0 |
| Pin 5 | PB4 (SS) β Port B bit 4 / SPI slave select |
| Pin 6 | PB5 (MOSI) β Port B bit 5 / SPI MOSI |
| Pin 7 | PB6 (MISO) β Port B bit 6 / SPI MISO |
| Pin 8 | PB7 (SCK) β Port B bit 7 / SPI SCK |
| Pin 9 | RESET β Reset input, active low |
| Pin 10 | VCC β Digital supply voltage |
| Pin 11 | GND β Digital ground |
| Pin 12 | XTAL2 β Crystal oscillator output |
| Pin 13 | XTAL1 β Crystal oscillator input |
| Pin 14 | PD0 (RXD) β Port D bit 0 / USART RXD |
| Pin 15 | PD1 (TXD) β Port D bit 1 / USART TXD |
| Pin 16 | PD2 (INT0) β Port D bit 2 / external interrupt 0 |
| Pin 17 | PD3 (INT1) β Port D bit 3 / external interrupt 1 |
| Pin 18 | PD4 (OC1B) β Port D bit 4 / Timer1 compare B |
| Pin 19 | PD5 (OC1A) β Port D bit 5 / Timer1 compare A |
| Pin 20 | PD6 (ICP1) β Port D bit 6 / Timer1 input capture |
| Pin 21 | PD7 (OC2) β Port D bit 7 / Timer2 compare |
| Pin 22 | PC0 (SCL) β Port C bit 0 / TWI SCL |
| Pin 23 | PC1 (SDA) β Port C bit 1 / TWI SDA |
| Pin 24 | PC2 (TCK) β Port C bit 2 / JTAG TCK |
| Pin 25 | PC3 (TMS) β Port C bit 3 / JTAG TMS |
| Pin 26 | PC4 (TDO) β Port C bit 4 / JTAG TDO |
| Pin 27 | PC5 (TDI) β Port C bit 5 / JTAG TDI |
| Pin 28 | PC6 (TOSC1) β Port C bit 6 / Timer0 async osc |
| Pin 29 | PC7 (TOSC2) β Port C bit 7 / Timer0 async osc |
| Pin 30 | AVCC β Analog supply voltage |
| Pin 31 | AGND β Analog ground |
| Pin 32 | AREF β ADC reference voltage |
| Pin 33 | PA7 (ADC7) β Port A bit 7 / ADC input 7 |
| Pin 34 | PA6 (ADC6) β Port A bit 6 / ADC input 6 |
| Pin 35 | PA5 (ADC5) β Port A bit 5 / ADC input 5 |
| Pin 36 | PA4 (ADC4) β Port A bit 4 / ADC input 4 |
| Pin 37 | PA3 (ADC3) β Port A bit 3 / ADC input 3 |
| Pin 38 | PA2 (ADC2) β Port A bit 2 / ADC input 2 |
| Pin 39 | PA1 (ADC1) β Port A bit 1 / ADC input 1 |
| Pin 40 | PA0 (ADC0) β Port A bit 0 / ADC input 0 |
Typical Applications
ATMEGA32A-PU is suitable for 6 applications: Arduino-Compatible Prototyping Boards, Industrial Automation Controllers, Sensor Hubs and Data Loggers, Smart Energy Meters, Consumer White Goods Control Boards, Educational and Hobby Robotics.
Arduino-Compatible Prototyping Boards
The ATMEGA32A-PU's 32 KB Flash and 16 MIPS throughput make it a strong candidate for Arduino-style prototyping boards that need more I/O than an Uno offers. With 32 programmable I/O lines and 8 ADC channels, it can drive multi-sensor shields, character LCDs, and stepper motors simultaneously without external I/O expanders. The 4.5-5.5 V supply aligns with classic 5 V Arduino shields, and the same avrdude toolchain that programs the ATmega328P programs the ATmega32A when the correct part signature is configured. JTAG debug on the device further simplifies bring-up of complex firmware.
Recommended
Industrial Automation Controllers
Industrial PLCs, motor controllers and remote I/O modules benefit from the ATMEGA32A-PU's -40 C to +85 C industrial temperature range, brown-out detector, and JTAG/OCD debug interface. The 16 MIPS throughput easily executes PID loops for brushed DC and stepper motors at sub-millisecond sample rates, while the 32 I/O lines can sink 20 mA per pin to directly drive relays, optocouplers and 7-segment displays without buffer transistors. The hardware multiplier accelerates 16-bit math commonly used in sensor linearization routines for thermocouples and load cells.
Recommended
Sensor Hubs and Data Loggers
Sensor hubs aggregate inputs from temperature, pressure and flow sensors; the ATMEGA32A-PU handles this with its 8-channel 10-bit ADC, two USARTs (via SPI/UART multiplexing), TWI (I2C) for digital sensors, and 1 KB of EEPROM for non-volatile calibration constants. The 32 KB Flash accommodates logging firmware plus lookup tables, while the 2 KB SRAM buffers packet data before transmission. Low-power sleep modes (as low as sub-microamp with the watchdog disabled) extend battery life in remote, solar-powered installations such as environmental monitors.
Recommended
Smart Energy Meters
Single-phase energy meters and sub-metering devices use the ATMEGA32A-PU to sample current and voltage channels with its 10-bit ADC while computing RMS power in real time. The hardware multiplier accelerates the multiply-accumulate steps of digital multiplication, and the on-chip EEPROM stores tariff schedules and tamper-event logs. The 5 V supply is convenient for powering from a capacitive-dropper or small switched-mode supply, while the JTAG port enables field calibration by OEMs without IC swaps.
Recommended
Consumer White Goods Control Boards
Washing machines, dishwashers, microwave ovens and air conditioners integrate an 8-bit MCU for user-interface control, sensor monitoring, and motor/valve actuation. The ATMEGA32A-PU offers enough Flash for state-machine firmware, enough I/O for keypad scanning and triac firing, and enough ADC channels for temperature and water-level sensors. Its 5 V tolerance simplifies interfacing with legacy triac-driver optocouplers, and the industrial temperature grade withstands the heat of appliance enclosures.
Recommended
Educational and Hobby Robotics
Robotics hobbyists and university embedded-systems courses rely on the ATMEGA32A-PU's 40-pin PDIP through-hole package for breadboard-friendly prototyping. The exposed JTAG pins allow students to step through C code instruction by instruction with a JTAGICE mkII or Atmel-ICE debugger, demystifying interrupt vectors, ADC registers and timer prescalers. With Arduino libraries still compatible (via the MightyCore core), learners can graduate from Arduino-style sketches to register-level firmware without changing silicon.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA32A-PU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA32-16PU | ATMEGA32A-PN | ATMEGA644A-PU | ATMEGA324A-PU |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-40 (PU) | PDIP-40 (PU) - same | PDIP-40 (PN) - same footprint, different temp range marking | PDIP-40 (PU) - same | PDIP-40 (PU) - same |
| Flash Memory | 32 KB | 32 KB | 32 KB | 64 KB | 32 KB |
| SRAM | 2 KB | 2 KB | 2 KB | 4 KB | 8 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 2 KB | 1 KB |
| Maximum Clock | 16 MHz | 16 MHz | 16 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 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 | 1.8 V to 5.5 V |
| I/O Pins | 32 | 32 | 32 | 32 | 32 |
| ADC Channels | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit |
Key Differentiators
- Wide operating voltage and industrial temperature range (vs ATMEGA328P-PU)
- 32 KB Flash with 8-channel ADC and JTAG (vs ATMEGA328P-PU)
- Pin-compatible upgrade path to 64 KB Flash (vs ATMEGA644A-PU)
Design Notes
Place a 100 nF decoupling capacitor within 5 mm of each VCC and AVCC pin, plus a 10 uF bulk capacitor near the MCU. The ATmega32A datasheet (DS40002072A) specifies AVCC must be within +/-0.3 V of VCC; a ferrite bead or small inductor between VCC and AVCC is recommended for noisy environments to keep ADC readings clean.
Route analog and digital grounds as a star converging on the AGND and GND pins respectively; never run digital return currents under the analog section. Keep ADC traces short and surrounded by an analog ground pour. For JTAG, route TCK, TMS, TDO and TDI as a matched-length group within 25 mm to preserve debug reliability.
Do not enable the internal brown-out detector (BOD) at a threshold above the minimum VCC of 4.5 V, or the device will reset continuously below 5 V rails. When using a 16 MHz crystal, choose a load capacitance matching the crystal datasheet (typical 12-22 pF) - too high causes slow startup, too low prevents oscillation. Disable the JTAGEN fuse if JTAG pins are needed as general I/O.
Compliance Information
RoHS compliant per Microchip product page. ATMEGA32A-PU carries the industrial -40 C to +85 C temperature grade. AEC-Q100 qualification is not applicable for general-purpose AVR MCUs.
