ATMEGA3290PA-AUR - 8-Bit AVR MCU 32KB 20MHz TQFP-100 | Microchip
MPN: ATMEGA3290PA-AUR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.62 | $4.62 |
| 10 | $4.16 | $41.60 |
| 100 | $3.68 | $368.00 |
| 500 | $3.31 | $1,655.00 |
| 1,000 | $2.95 | $2,950.00 |
ATMEGA3290PA-AUR Overview
An 8-bit microcontroller is a single-chip processor whose data bus is eight bits wide, executing one byte per instruction cycle. Within the power-management hierarchy, it integrates CPU, memory, timers, communication peripherals, and an LCD controller on one die, replacing multi-chip solutions and reducing board area, BOM cost, and system power. The AVR family is a Harvard-architecture RISC line originally developed by Atmel, now part of Microchip Technology.
Key features include 131 powerful instructions with mostly single-clock-cycle execution, high throughput of up to 20 MIPS at 20MHz, and advanced power-management modes including idle, power-save, power-down, standby, and extended standby that exploit the picoPower technology of the PA suffix for ultra-low sleep currents. The embedded 4x40 segment LCD driver directly drives glass displays without external driver ICs, a differentiator that defines this device family.
Architecturally, the device uses a Harvard design with separate program and data buses, self-programmable Flash for boot-loader firmware updates, and on-chip debug via debugWIRE. Peripherals include two 8-bit timer/counters with separate prescaler and compare mode, one 16-bit timer/counter, USART, SPI, and analog comparators typical of the ATmega LCD family.
Typical applications include utility metering (electricity, water, gas meters with LCD glass), industrial control panels with segmented displays, and portable instruments where the picoPower sleep modes extend battery life for years.
Design consideration: full 20MHz operation requires a supply of 4.5V to 5.5V; derate clock speed for lower supply voltages per the Speed/Grade versus Voltage curve in the manufacturer datasheet.
This page synthesizes distributor availability, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA3290PA-AUR — 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 ATMEGA3290PA-AUR (same form factor and footprint) — differing in Package, LCD Controller, Operating Temperature, RoHS Status, Instructions.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA3290PA-AU
✅ Drop-In✓ In Stock
$4.48 / Unit
View Datasheet →ATMEGA3250PA-AUR
✅ Drop-In✓ In Stock
$2.98 / Unit
View Datasheet →ATMEGA3250A-AUR
✅ Drop-In✓ In Stock
$3.55 / Unit
View Datasheet →ATMEGA6490A-AUR
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA3250V-8AUR
✅ Drop-In✓ In Stock
$3.38 / Unit
View Datasheet →ATMEGA3290PA-AUR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR |
| Core Size | 8-Bit |
| Program Memory Type | FLASH |
| Program Memory Size | 32KB (16K x 16) |
| RAM Size | 2KB |
| EEPROM Size | 1KB |
| Maximum Clock Frequency | 20 MHz |
| Supply Voltage Range | 4.5 V to 5.5 V |
| Instruction Set | 131 powerful instructions, most single-clock cycle |
| LCD Driver | 4 x 40 Segment LCD Driver |
| Timers | Two 8-bit timer/counters with separate prescaler and compare mode; one 16-bit timer/counter |
| Package | TQFP-100 (14x14 mm), 0.8 mm pitch |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Programming Method | In-System Programmable (ISP), self-programming Flash |
| Power Modes | Idle, Power-save, Power-down, Standby, Extended Standby (picoPower) |
| RoHS Status | Green / Compliant (per FindIC listing) |
ATMEGA3290PA-AUR tqfp-100 (14x14 mm), 0.8 mm pitch Pin Configuration Guide
Pin configuration for ATMEGA3290PA-AUR (tqfp-100 (14x14 mm), 0.8 mm pitch 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 ATMEGA3290PA-AUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA3290PA-AUR is suitable for 6 applications: Utility Metering (Electricity / Water / Gas), Industrial Control Panels with LCD, Battery-Powered Portable Instruments, Building Automation and HVAC Controllers, Consumer Appliance Display Boards, POS Terminals and Payment Accessories.
Utility Metering (Electricity / Water / Gas)
The ATMEGA3290PA-AUR fits utility metering because its integrated 4x40 segment LCD driver directly drives the meter glass display without an external LCD controller, and its picoPower sleep modes cut average current to microamp levels between measurement cycles. The 32KB self-programmable Flash stores metering firmware and tariff tables, while 1KB EEPROM holds calibration and consumption data that must survive power loss. The 20MHz core at 4.5V-5.5V supplies enough headroom for pulse-counting and communication tasks. Designers typically run the device in power-save mode with an asynchronous timer wake-up for periodic accumulation, achieving years of battery-backed operation in water and gas meters.
Recommended
Industrial Control Panels with LCD
Industrial operator panels need a processor that shows status on a segmented LCD while scanning buttons and driving outputs - exactly the combination the ATMEGA3290PA-AUR provides with its on-chip 4x40 segment LCD driver, two 8-bit timers and one 16-bit timer, and 82 configurable I/O lines. The -40C to +85C industrial temperature grade and 4.5V-5.5V operation suit factory environments with noisy 5V rails. The 100-pin TQFP (14x14 mm, 0.8 mm pitch) footprint routes the large pin count on two-layer boards, keeping panel-controller BOM cost low. In-System Programming allows field firmware updates through a boot loader without desoldering the MCU, simplifying maintenance of deployed panel fleets.
Recommended
Battery-Powered Portable Instruments
Portable instruments benefit from the picoPower (PA) generation of this device: idle, power-save, power-down, standby, and extended standby modes reduce sleep current dramatically compared with the non-PA A-generation parts, directly extending battery life. The 4x40 segment LCD draws negligible power relative to dot-matrix alternatives, and the 16-bit timer supports precise measurement intervals from a watch-crystal in power-save mode. Although full 20MHz needs 4.5V-5.5V, designs typically clock slower at lower duty cycles. The 100-TQFP package is hand-assemblable for prototype builds, and 32KB Flash plus 2KB RAM accommodates protocol stacks and display menus typical of handheld instrumentation.
Recommended
Building Automation and HVAC Controllers
Thermostats and zone controllers require a readable display, EEPROM-writable setpoints, and reliable timer functions - all native to the ATMEGA3290PA-AUR. The on-chip LCD driver renders temperature and mode on standard segmented glass, 1KB EEPROM stores user setpoints through power cycles, and the USART/SPI peripherals link to RS-485 transceivers for networked HVAC buses. The industrial -40C to +85C rating covers unconditioned mechanical rooms. At 20MHz with single-cycle execution, PID loops for damper and valve control execute comfortably within scan cycles. Family pin compatibility (3250/3290/6490 in 100-TQFP) lets one PCB serve multiple controller SKUs by swapping MCU variants and firmware.
Recommended
Consumer Appliance Display Boards
White-goods and appliance control boards traditionally pair an 8-bit MCU with an LCD glass; the ATMEGA3290PA-AUR consolidates both into one 100-TQFP device, cutting component count and assembly cost. The green/RoHS-compliant package supports consumer environmental requirements, and the 5V, 20MHz operation aligns with appliance mains-derived supplies. Self-programmable Flash enables manufacturing-line firmware loading and post-sale feature updates. The large pin count provides the dozens of I/O lines appliance boards need for relays, buttons, and encoders while the LCD driver handles the 4x40 segment display. PicoPower standby modes support low-wattage off-mode energy regulations now common in household appliance standards.
Recommended
POS Terminals and Payment Accessories
Low-cost point-of-sale peripherals - customer displays, keypads, and receipt accessories - use the ATMEGA3290PA-AUR for its segmented LCD output, ample I/O, and EEPROM storage of serial numbers and configuration. The 100-pin TQFP supplies enough pins for matrix keypad scanning and display drive from a single chip, and the AVR toolchain (AVR GCC, MPLAB-compatible ecosystem) keeps software costs near zero. Tape-and-reel -AUR packaging feeds pick-and-place lines in volume assembly, while the industrial temperature grade tolerates outdoor kiosk enclosures. Field firmware updates via self-programming Flash allow payment-accessory vendors to patch protocol firmware across installed bases without hardware recall.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA3290PA-AUR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA3290PA-AU | ATMEGA3250PA-AUR | ATMEGA3250A-AUR | ATMEGA6490A-AUR | ATMEGA3250V-8AUR |
|---|---|---|---|---|---|---|
| Package | TQFP-100 (14x14 mm, 0.8 mm pitch) | TQFP-100 (14x14) - same | TQFP-100 (14x14) - same | TQFP-100 (14x14) - same | TQFP-100 (14x14) - same | TQFP-100 (14x14) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock | 20 MHz | 20 MHz | 20 MHz | 16 MHz | 16 MHz | 8 MHz |
| SRAM | 2KB | 2KB | 2KB | 2KB | 4KB | 2KB |
| LCD Driver | 4 x 40 segments | 4 x 40 segments | 4 x 40 segments | 4 x 40 segments | 4 x 40 segments | 4 x 40 segments |
| Power Technology | picoPower (PA) | picoPower (PA) | picoPower (PA) | standard (A) | standard (A) | low-voltage (V) |
| Packaging | Tape & Reel | Tray | Tape & Reel | Tape & Reel | Tape & Reel | Tape & Reel |
Key Differentiators
- picoPower generation sleep current (vs ATMEGA3250A-AUR)
- Cost-effective 32KB tier (vs ATMEGA6490A-AUR)
- Full-speed 5V operation (vs ATMEGA3250V-8AUR)
- Tape-and-reel production packaging (vs ATMEGA3290PA-AU)
Design Notes
The ATMEGA3290PA-AUR requires 4.5V-5.5V for full 20MHz operation per the manufacturer datasheet. Never clock this device beyond the Speed versus Voltage curve - running 20MHz at 4.0V causes marginal instruction execution and intermittent failures that are hard to diagnose. If your board is 3.3V, do not use this AUR part; select a V-grade family member such as ATMEGA3250V-8AUR (2.7V-5.5V, 8MHz max) which shares the same 100-TQFP footprint. Add 100nF decoupling on each VCC/AVCC pair plus bulk 10uF near the regulator.
The 100-pin TQFP has 0.8 mm pitch - specify 0.5 mm-pitch-capable solder paste and inspect with AOI, since bridging between LCD-drive pins is the most common assembly defect on this family. Place the 32.768kHz watch crystal for the asynchronous timer (used in power-save mode) close to the device with short guard traces and a ground ring to preserve picoPower sleep current performance. Keep the ISP (SPI) header routed to pins dedicated to programming so field firmware updates remain possible after LCD routing consumes surrounding area.
Do not mix up PA and non-PA power expectations: the ATMEGA3250A/6490A A-generation parts have higher sleep current than this PA part, so a PCB designed around picoPower standby budgets will fail battery-life targets if a sourcing substitution to an A-grade part occurs silently. Also verify firmware register compatibility when substituting 3250/3290/6490 variants - LCD segment mapping and peripheral register layouts differ within the family even though the footprint is identical. Re-compile and bench-test LCD drive with the actual glass before approving any alternate MPN.
Compliance Information
FindIC and DigiKey listings describe the ATMEGA3290PA-AUR as GREEN T&R (halogen-free/lead-free packaging). Full REACH and conflict-minerals declarations should be confirmed on the Microchip product page.
