ATMEGA88A-AU - 8KB AVR 20MHz MCU TQFP-32 | Microchip
MPN: ATMEGA88A-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.35 | $2.35 |
| 10 | $2.12 | $21.20 |
| 100 | $1.88 | $188.00 |
| 500 | $1.69 | $845.00 |
| 1,000 | $1.52 | $1,520.00 |
ATMEGA88A-AU Overview
An AVR microcontroller is a Harvard-architecture 8-bit RISC device that executes most instructions in a single clock cycle, sitting within the hierarchy of microcontroller -> embedded processor -> integrated circuit -> semiconductor. The ATmega family is the classic general-purpose AVR line, and the ATmega88A is its 8 KB Flash member, offering a balanced mix of memory, peripherals, and low power for cost-sensitive embedded designs.
Key features include 8 KB of in-system programmable Flash with read-while-write, 512 B EEPROM for non-volatile parameter storage, 1 KB SRAM, 23 programmable I/O lines, and 32 general-purpose working registers. Three flexible timer/counters with compare modes, a byte-oriented Two-Wire serial interface (TWI/I2C), a programmable USART, and an 8-channel 10-bit ADC cover most embedded control needs without external glue logic.
The device uses Microchip picoPower technology, achieving sub-1 uA power-down current and multiple sleep modes, which makes it well suited to battery-powered and always-on sensing products. The 20 MHz maximum clock at 4.5-5.5 V supports 20 MIPS throughput, while the 1.8 V minimum supply allows direct operation from single-cell Li-Ion or 2xAA rails.
Typical applications include consumer appliance control panels, industrial sensor nodes, battery-powered IoT endpoints, motor control front-ends, and legacy ATmega8/ATmega88 board upgrades. The TQFP-32 footprint is shared across the ATmega48A/88A/168A/328A family, allowing firmware and layout reuse.
When designing with the ATMEGA88A-AU, decouple every VCC/AVCC pin with 100 nF ceramic capacitors placed within a few millimeters of the pin, and add a 10 uF bulk capacitor near the regulator. The internal calibrated RC oscillator removes the need for an external crystal in many applications, but an external 16 MHz crystal is recommended when precise UART baud rates or USB-serial bridging are required.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, giving engineers a single reference for selection, replacement, and layout decisions.
Drop-in alternatives for ATMEGA88A-AU 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 ATMEGA88A-AU (same form factor and footprint) β differing in Package, Operating Temperature, Serial Interfaces, Throughput, Supply Voltage Range.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA88PA-AU
β Drop-Inβ In Stock
$1.21 / Unit
View Datasheet βATMEGA88-20AU
β Drop-Inβ In Stock
$2.33 / Unit
View Datasheet βATMEGA168A-AU
β Drop-Inβ In Stock
$1.42 / Unit
View Datasheet βATMEGA328P-AU
β Drop-Inβ In Stock
$1.85 / Unit
View Datasheet βATMEGA48A-AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA8A-AU
β Drop-Inβ In Stock
$1.31 / Unit
View Datasheet βATMEGA88A-AU Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Program Memory Size | 8 KB (4K x 16) Flash |
| Program Memory Type | Flash (ISP, read-while-write) |
| EEPROM | 512 B |
| SRAM | 1 KB |
| Maximum Clock Frequency | 20 MHz |
| Operating Voltage Range | 1.8 V to 5.5 V |
| Supply Voltage (20 MHz operation) | 4.5 V to 5.5 V |
| General Purpose I/O Lines | 23 |
| General Purpose Working Registers | 32 |
| ADC | 8-channel, 10-bit successive approximation |
| Timers/Counters | 3 (two 8-bit, one 16-bit) with compare modes |
| Serial Interfaces | USART, SPI, TWI (I2C) |
| Package | 32-pin TQFP (7x7 mm, 0.80 mm pitch) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 C to +85 C |
| Instruction Set | 130 powerful instructions, most single-clock cycle |
| Power-Down Current | Sub-1 uA (picoPower technology) |
| RoHS Status | Compliant |
| Packaging | Tray |
ATMEGA88A-AU Pin Configuration
| Pin 1 | PD3 β Port D bit 3 / INT1 / OC2B |
| Pin 2 | PD4 β Port D bit 4 / T0 / XCK |
| Pin 3 | GND β Ground |
| Pin 4 | VCC β Digital supply voltage |
| Pin 5 | GND β Ground |
| Pin 6 | VCC β Digital supply voltage |
| Pin 7 | PB6 β Port B bit 6 / XTAL1 / TOSC1 |
| Pin 8 | PB7 β Port B bit 7 / XTAL2 / TOSC2 |
| Pin 9 | PD5 β Port D bit 5 / T1 / OC0B |
| Pin 10 | PD6 β Port D bit 6 / AIN0 / OC0A |
| Pin 11 | PD7 β Port D bit 7 / AIN1 |
| Pin 12 | PB0 β Port B bit 0 / ICP1 / CLKO |
| Pin 13 | PB1 β Port B bit 1 / OC1A |
| Pin 14 | PB2 β Port B bit 2 / SS / OC1B |
| Pin 15 | PB3 β Port B bit 3 / MOSI / OC2A |
| Pin 16 | PB4 β Port B bit 4 / MISO |
| Pin 17 | PB5 β Port B bit 5 / SCK |
| Pin 18 | AVCC β Analog supply voltage for ADC |
| Pin 19 | ADC6 β Analog input channel 6 |
| Pin 20 | AREF β Analog reference voltage |
| Pin 21 | GND β Ground |
| Pin 22 | ADC7 β Analog input channel 7 |
| Pin 23 | PC0 β Port C bit 0 / ADC0 |
| Pin 24 | PC1 β Port C bit 1 / ADC1 |
| Pin 25 | PC2 β Port C bit 2 / ADC2 |
| Pin 26 | PC3 β Port C bit 3 / ADC3 |
| Pin 27 | PC4 β Port C bit 4 / ADC4 / SDA |
| Pin 28 | PC5 β Port C bit 5 / ADC5 / SCL |
| Pin 29 | PC6 β Port C bit 6 / RESET |
| Pin 30 | PD0 β Port D bit 0 / RXD |
| Pin 31 | PD1 β Port D bit 1 / TXD |
| Pin 32 | PD2 β Port D bit 2 / INT0 |
Typical Applications
ATMEGA88A-AU is suitable for 6 applications: Battery-Powered IoT Sensor Nodes, Industrial Sensor and Control Nodes, Consumer Appliance Control Panels, Motor Control Front-Ends, Legacy ATmega8 / ATmega88 Board Upgrades, Educational and Prototyping Platforms.
Battery-Powered IoT Sensor Nodes
The ATMEGA88A-AU fits battery-powered IoT sensor nodes because its picoPower technology draws sub-1 uA in power-down mode and the device operates from 1.8 V to 5.5 V, allowing direct connection to single-cell Li-Ion or 2xAA rails without a boost converter. The integrated 8-channel 10-bit ADC samples analog sensors such as thermistors, photodiodes, and strain gauges, while the TWI (I2C) interface connects digital sensors like accelerometers and humidity sensors. In a typical duty-cycled design the MCU wakes on a timer interrupt, samples the sensor, transmits over USART or SPI to a radio module, then returns to power-down. The trade-off is that 8 KB Flash limits protocol stack size, so lightweight custom protocols are preferred over full TCP/IP stacks.
Recommended
Industrial Sensor and Control Nodes
The ATMEGA88A-AU suits industrial sensor and control nodes because its -40 C to +85 C operating range, 5 V tolerant I/O, and 20 MHz throughput handle factory-floor environments where noise immunity and deterministic timing matter. Three timer/counters with compare modes generate precise PWM for valve and heater control, while the 10-bit ADC reads 4-20 mA loop sensors through a sense resistor. The USART supports Modbus RTU at standard baud rates when paired with an external RS-485 transceiver. Unlike a 3.3 V-only MCU, the 5 V supply option simplifies interfacing to legacy industrial logic. The limitation is that 23 I/O lines constrain very large I/O counts, so expansion via I2C port expanders may be required.
Recommended
Consumer Appliance Control Panels
The ATMEGA88A-AU is widely used in consumer appliance control panels because its 8 KB Flash holds button-scan, display-drive, and safety-interlock firmware, while 23 I/O lines directly drive LEDs, relays, and buzzer outputs without external drivers. The internal calibrated RC oscillator eliminates the external crystal in cost-sensitive designs, reducing BOM count and board area. The 10-bit ADC reads potentiometers or thermistor inputs for temperature and user-setting control. In a washing machine or coffee maker, the MCU runs a state machine that sequences motors, heaters, and valves under watchdog supervision. The trade-off is that 1 KB SRAM limits large display buffers, so segment or char displays are preferred over graphical LCDs.
Recommended
Motor Control Front-Ends
The ATMEGA88A-AU serves as a motor control front-end because its 16-bit Timer/Counter1 generates complementary PWM with dead-time control for half-bridge gate drivers, and the 10-bit ADC samples current-shunt feedback for overcurrent protection. At 20 MHz the control loop can run at several kHz, sufficient for brushed DC and small stepper motors. The USART or SPI interface accepts commands from a host controller, and the analog comparator enables fast fault detection without ADC latency. For BLDC motors, the ADC and comparator together implement sensorless back-EMF zero-crossing detection. The limitation is that 8 KB Flash restricts advanced FOC algorithms, so trapezoidal commutation is the practical choice.
Recommended
Legacy ATmega8 / ATmega88 Board Upgrades
The ATMEGA88A-AU is a natural upgrade for legacy ATmega8 and ATmega88 boards because it shares the 32-pin TQFP footprint and AVR instruction set, so existing PCBs can be re-populated without layout changes. Compared with the original ATmega8, the ATmega88A adds more flexible timer/counter modes, a byte-oriented TWI interface, and improved picoPower sleep currents. Firmware migration requires recompiling for the ATmega88A device and reviewing register names that changed between families, such as timer prescaler and USART control bits. The 8 KB Flash matches the ATmega8, so code size is not a barrier. This makes the part attractive for extending the life of mature products without a full redesign.
Recommended
Educational and Prototyping Platforms
The ATMEGA88A-AU is well suited to educational and prototyping platforms because the AVR instruction set is simple to teach, the device is supported by free toolchains such as Atmel Studio and avr-gcc, and the 32-pin TQFP package is easy to route on two-layer boards. Students can program the part via ISP using a low-cost programmer, and the 23 I/O lines are enough for LED matrices, keypads, and small motor projects. The 10-bit ADC and PWM peripherals support analog experiments without external instruments. The trade-off versus the ATmega328P is smaller memory, which limits Arduino-style libraries, so bare-metal or lightweight frameworks are recommended for coursework.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA88A-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA88PA-AU | ATMEGA168A-AU | ATMEGA328P-AU | ATMEGA48A-AU |
|---|---|---|---|---|---|
| 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 |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 8 KB | 16 KB | 32 KB | 4 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 2 KB | 512 B |
| EEPROM | 512 B | 512 B | 512 B | 1 KB | 256 B |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage Range | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| GPIO Lines | 23 | 23 | 23 | 23 | 23 |
| ADC Channels / Resolution | 8-channel, 10-bit | 8-channel, 10-bit | 8-channel, 10-bit | 8-channel, 10-bit | 8-channel, 10-bit |
| Power-Down Current | Sub-1 uA (picoPower) | Sub-1 uA (picoPower, improved) | Sub-1 uA (picoPower) | Sub-1 uA (picoPower) | Sub-1 uA (picoPower) |
Key Differentiators
- Lowest-cost 8 KB member of the pin-compatible ATmega family (vs ATMEGA328P-AU)
- picoPower low-power operation (vs ATMEGA8A-AU)
- Integrated TWI (I2C) and flexible timer modes (vs ATMEGA8A-AU)
- Firmware and layout reuse across the ATmega48A/88A/168A/328A family (vs ATMEGA168A-AU)
Design Notes
Decouple every VCC and AVCC pin with a 100 nF ceramic capacitor placed within a few millimeters of the pin, and add a 10 uF bulk capacitor near the regulator output. AVCC should be connected to VCC through a low-pass filter (10 uH inductor or 10 ohm resistor plus 100 nF) when the ADC is used, to keep digital switching noise out of the analog reference. AREF should be decoupled with 100 nF to GND when using the internal reference.
Route the crystal or resonator as close as possible to XTAL1 (pin 7) and XTAL2 (pin 8) with short, symmetric traces, and place the two load capacitors directly at the pins with a solid ground return. Keep the ISP header (MOSI, MISO, SCK, RESET) traces short and away from switching nodes. For the TQFP-32 package, use a thermal-relief ground plane under the device and avoid routing high-current traces beneath the analog pins PC0-PC5.
Do not leave the RESET pin floating; add an external 10 kohm pull-up to VCC and a 100 nF capacitor to GND for noise immunity, even though the device has an internal pull-up. Ensure the brown-out detector (BOD) is enabled in the fuse settings for reliable operation during slow power ramps. When migrating firmware from ATmega8 or ATmega88, verify timer prescaler and USART register names, as they differ between families and can cause silent timing errors.
Estimated: at 5 V and 20 MHz the ATMEGA88A-AU core current is typically a few milliamps, so self-heating is negligible in the TQFP-32 package and no heatsink is required. Junction temperature rise can be estimated as P x theta_JA; with theta_JA on the order of 60-80 C/W for a 7x7 mm TQFP on a two-layer board, even 100 mW dissipation raises the junction by less than 10 C. Verify against the datasheet thermal characteristics for your specific copper area.
Compliance Information
Distributor data lists the ATMEGA88A-AU as RoHS compliant and lead-free. REACH, halogen-free, and conflict-minerals status were not stated in the retrieved web data and are marked unknown; confirm with the Microchip product page or material declaration before finalizing compliance documentation.
