ATMEGA3290-16AI - AVR 8-bit MCU 16MHz 32KB TQFP-100 | Microchip
MPN: ATMEGA3290-16AI ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.9 | $6.90 |
| 10 | $6.21 | $62.10 |
| 100 | $5.52 | $552.00 |
| 500 | $4.83 | $2,415.00 |
| 1,000 | $4.14 | $4,140.00 |
ATMEGA3290-16AI Overview
A microcontroller unit (MCU) is a single integrated circuit that combines a processor core, program memory, data memory, and peripherals into one chip, forming the lowest tier of the embedded processing hierarchy below application processors and system-on-chip devices. The AVR ATmega family uses an advanced RISC architecture with 130 mostly single-cycle instructions and 32 general-purpose working registers, allowing one instruction per clock cycle for efficient C and assembly code execution.
Key features of the ATMEGA3290-16AI include self-programming Flash with read-while-write capability for in-system updates, 69 general-purpose I/O lines for large button- and display-intensive designs, an integrated LCD controller driving up to 100/132 LCD segment configurations, and serial connectivity via SPI, UART/USART, and USI interfaces. The picoPower technology supports multiple sleep modes, minimizing power draw in battery-operated and standby-critical systems.
Technically, the device operates from 2.7 V to 5.5 V and achieves 16 MIPS throughput at 16 MHz. The built-in LCD driver eliminates an external LCD controller, reducing BOM cost and board area in segmented-display products. The JTAG interface supports on-chip debugging and boundary-scan testing of the dense 100-lead footprint.
Typical applications include industrial control panels with segmented LCDs, utility metering front ends, HVAC and appliance user interfaces, and security or access-control terminals where many I/O and a local display coexist on one controller.
Design consideration: clock selection and BOD fuse settings strongly influence both power consumption and reset reliability; verify fuse configuration before production programming, since the TQFP-100 package makes field rework impractical.
This page adds distributor pricing context, drop-in alternatives within the ATmega LCD family, and practical design guidance synthesized from multiple sources beyond the manufacturer datasheet.
Drop-in alternatives for ATMEGA3290-16AI — 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 ATMEGA3290-16AI (same form factor and footprint) — differing in Package, Supply Voltage Range, RoHS Status, Instructions, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA3290P-20AUR
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →ATMEGA3290V-8AU
✅ Drop-In✓ In Stock
$3.91 / Unit
View Datasheet →ATMEGA3250-16AU
✅ Drop-In✓ In Stock
$5.74 / Unit
View Datasheet →ATMEGA3250P-20AUR
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA3250PA-AUR
✅ Drop-In✓ In Stock
$2.98 / Unit
View Datasheet →ATMEGA3250V-8AUR
✅ Drop-In✓ In Stock
$3.38 / Unit
View Datasheet →ATMEGA3290-16AI Maximum Ratings & Electrical Characteristics
| Core Architecture | AVR 8-bit RISC, 130 instructions |
| Flash Program Memory | 32 KB (16K x 16) |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Maximum Clock Frequency | 16 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V |
| General Purpose I/O | 69 I/O lines |
| Serial Interfaces | SPI, UART/USART, USI |
| LCD Controller | Integrated segmented LCD driver |
| Working Registers | 32 x 8-bit general purpose |
| Package | 100-TQFP (14 x 14 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Low Power Technology | picoPower AVR, multiple sleep modes |
| Debug Interface | JTAG (on-chip debug, boundary scan) |
| In-System Programming | Yes (self-programming Flash, read-while-write) |
| RoHS Status | Compliant (RoHS per distributor listings) |
ATMEGA3290-16AI 100-tqfp (14 x 14 mm) Pin Configuration Guide
Pin configuration for ATMEGA3290-16AI (100-tqfp (14 x 14 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA3290-16AI.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA3290-16AI is suitable for 6 applications: Industrial Control Panels with Segmented LCD, Utility Metering (Energy/Water/Gas), HVAC and Appliance User Interfaces, Security and Access Control Terminals, Portable and Battery-Powered Instruments, Building Automation Nodes.
Industrial Control Panels with Segmented LCD
The ATMEGA3290-16AI fits industrial panel designs because it combines a 16 MHz AVR core, 69 GPIO lines, and an integrated segmented LCD controller in one 100-TQFP device, eliminating a separate LCD driver IC and reducing board area and BOM cost. The -40C to +85C industrial rating covers uncontrolled factory-floor cabinets, while the 2.7 V to 5.5 V supply range tolerates noisy 5 V rails. In a typical panel, the MCU drives the segmented display directly, scans a matrix keypad via GPIO, and reports status over UART or SPI to a PLC. Because the Flash is self-programming with read-while-write, field firmware updates and event logging can coexist without halting display refresh; picoPower sleep modes cut standby draw in always-on installations.
Recommended
Utility Metering (Energy/Water/Gas)
Metering front ends benefit from the ATMEGA3290-16AI's combination of 32 KB self-programming Flash, 1 KB EEPROM for tariff and calibration data, and an LCD controller that drives consumption digits and icons directly at 5 V or 3.3 V. The USI and SPI interfaces connect to metering front-end ICs, while the UART links to AMR (automatic meter reading) modules. Read-while-write Flash lets the device log usage events into emulated EEPROM without interrupting measurement loops running at up to 16 MIPS. The industrial temperature rating keeps calibration stable in outdoor meter cabinets, and picoPower sleep modes extend battery life in battery-backed water and gas meters where the display wakes only on demand.
Recommended
HVAC and Appliance User Interfaces
Thermostats, boiler controllers, and white-goods user interfaces use the ATMEGA3290-16AI to merge display, keypad, and control logic in one chip: the segmented LCD shows temperature setpoints and menus, the 69 GPIO lines drive relays, fans, and dampers, and the ADC-era AVR peripherals handle sensor polling over SPI or USI. The 2.7 V to 5.5 V range supports both 3.3 V logic and 5 V relay-drive designs, and the -40C rating tolerates unheated equipment rooms. Self-programming Flash allows OTA-style updates delivered through the UART during service windows. Firmware written for 16 MHz operation ports unchanged to the pin-compatible ATMEGA3290P-20AUR, providing a low-risk upgrade path for lower standby power.
Recommended
Security and Access Control Terminals
Access-control keypads and alarm panels exploit the ATMEGA3290-16AI's large I/O count to scan big key matrices, drive LEDs and a status LCD, and communicate over UART or SPI with RFID readers and network modules. The JTAG interface supports boundary-scan test of the dense 100-lead board during production and on-chip debugging during development, reducing test-fixture complexity. The 1 KB EEPROM stores user codes and event logs across power cycles, while read-while-write Flash permits log rotation without stopping the scanning loop. With 16 MIPS at 16 MHz, response times stay well below human perception thresholds even with heavy keypad debouncing and display refresh running concurrently.
Recommended
Portable and Battery-Powered Instruments
Handheld meters and portable test instruments use the ATMEGA3290-16AI's picoPower sleep modes and the low-power ATMEGA3290V-8AU drop-in variant (1.8 V to 5.5 V) to maximize battery life while keeping a segmented LCD and full keypad. At 16 MIPS the AVR handles signal processing such as RMS calculation and filtering, while the LCD controller and 69 GPIO handle user interface without extra driver ICs. The 2 KB SRAM buffers measurement sweeps, and the self-programming Flash stores calibration routines applied at production and recalibration. The industrial temperature grade ensures the instrument remains within specification when moved from cold vehicles to warm interiors, avoiding condensation-related reset issues when combined with proper brown-out fuse settings.
Recommended
Building Automation Nodes
Room controllers and damper/valve actuators in building automation use the ATMEGA3290-16AI as a self-contained node: UART or SPI links to field buses and sensor boards, GPIO drives actuators, and the LCD panel gives local status for commissioning. The 16 MHz clock provides headroom for PID loops on multiple channels, and the 1 KB EEPROM retains setpoints through outages. The industrial -40C to +85C range covers rooftop and mechanical-room installations, and the 5 V tolerance of the I/O simplifies interfacing with legacy 24 V-derived sensor signaling through simple conditioning. JTAG boundary scan supports panel-level production test, while the drop-in ATMEGA3290P-20AUR offers an easy migration to lower standby consumption in next-generation nodes.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA3290-16AI — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA3290P-20AUR | ATMEGA3290V-8AU | ATMEGA3250-16AU | ATMEGA3250PA-AUR |
|---|---|---|---|---|---|
| Package | 100-TQFP (14 x 14 mm) | 100-TQFP (14 x 14 mm) - same | 100-TQFP (14 x 14 mm) - same | 100-TQFP (14 x 14 mm) - same | 100-TQFP (14 x 14 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 32 KB | 32 KB | 32 KB | 32 KB | 32 KB |
| SRAM / EEPROM | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB | 2 KB / 1 KB |
| Max Clock Frequency | 16 MHz | 20 MHz | 8 MHz | 16 MHz | 20 MHz |
| Supply Voltage | 2.7 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 2.7 V to 5.5 V | 1.8 V to 5.5 V |
| GPIO / LCD | 69 GPIO, LCD controller | 69 GPIO, LCD controller | 69 GPIO, LCD controller | Fewer GPIO, different LCD partition | Fewer GPIO, different LCD partition |
Key Differentiators
- Higher clock ceiling within the same footprint (vs ATMEGA3290P-20AUR)
- Full industrial temperature rating (vs ATMEGA3290-16AU)
- Maximum I/O budget in the LCD AVR family (vs ATMEGA3250-16AU)
Design Notes
Set the brown-out detector (BOD) fuse appropriately for the supply rail: at 5 V systems use the higher BOD level to guarantee Flash writes are safe, and enable BOD-in-sleep in picoPower parts to cut standby current. On the ATMEGA3290-16AI, incorrect BOD settings are the most common cause of EEPROM corruption during brownouts in panel products. Verify all fuses (clock source, JTAGEN, SPIEN, BOOTRST) with a programmer read-back before mass production, since TQFP-100 rework in the field is impractical.
The 100-TQFP (0.5 mm pitch, 14 x 14 mm) footprint requires attention to fanout: keep decoupling capacitors (100 nF per supply pin pair) on the bottom layer directly under the package with short vias. The integrated LCD driver demands a stable LCD bias supply; follow the datasheet's recommended capacitor values on VLCD and bias divider pins, and route LCD segment traces away from switching or UART lines to avoid ghosting on the glass.
Do not assume ATmega3250 drop-in equivalence without checking I/O and LCD segmentation: the ATmega3250 parts share the footprint and memory set but expose fewer GPIO lines and a different LCD segment map than the ATmega3290, so designs using all 69 I/O lines will break. Also confirm the -16 speed grade frequency-versus-voltage curve in the datasheet when running below 4.5 V; 16 MHz is only guaranteed near the top of the 2.7 V to 5.5 V range.
For JTAG debugging and boundary-scan production test, bring the TDI/TDO/TMS/TCK pins to a 2x5 tag-connect-compatible header. Because the 100-pin package buries many signals, planning JTAG access at layout time avoids sacrificing in-circuit debugging later. Keep the JTAG chain enabled only during development and disable JTAGEN fuse in production to free PC7 as I/O and improve security.
Compliance Information
RoHS compliance indicated by distributor listings (DigiKey/Mouser). REACH, halogen-free, and conflict-minerals status not stated in provided data.
