ATMEGA649P-AUR - AVR 8-bit MCU 64KB Flash LCD | Microchip
MPN: ATMEGA649P-AUR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.21 | $7.21 |
| 10 | $6.49 | $64.90 |
| 100 | $5.83 | $583.00 |
| 500 | $5.25 | $2,625.00 |
| 1,000 | $4.72 | $4,720.00 |
ATMEGA649P-AUR Overview
An 8-bit AVR microcontroller (MCU) is a Harvard-architecture processor that executes most instructions in a single clock cycle, sitting within the broader hierarchy of embedded processors under microcontrollers, under the power- and cost-sensitive embedded systems category. The ATmega649P belongs to the ATmega LCD series (ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P family), which pairs general-purpose MCU peripherals with a segment LCD driver for glass-driving applications.
Key features include 54/69 general purpose I/O lines, 32 general purpose working registers, a JTAG interface for on-chip debug and boundary scan, and picoPower technology for ultra-low sleep-mode consumption. The P-suffix devices are drop-in replacements for the non-P ATmega649, produced on an improved process with lower power figures, and are subject to the same qualification and production test flow per Microchip application note AVR534.
The peripheral set includes an 8-bit timer/counter with PWM, a 16-bit timer/counter, SPI, USART, an analog comparator, a 10-bit ADC on related family members, and an LCD controller capable of driving segment glass directly - eliminating an external LCD driver IC in metering and appliance designs. ISP Flash with read-while-write allows firmware updates in the field without halting execution.
Typical applications include utility metering (energy and water meters with LCD displays), battery-powered handheld instruments, white-goods appliance panels, and industrial HMI front-ends where the integrated LCD driver and low sleep current extend battery life.
Design consideration: the picoPower benefits are realized only with correct sleep-mode selection (power-save or standby) and disabled unused peripherals; the 16MHz maximum CPU frequency is voltage-dependent, so derate clock speed at the low end of the supply range.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA649P-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 ATMEGA649P-AUR (same form factor and footprint) — differing in Core Architecture, EEPROM, Package, SRAM, LCD Controller.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA649A-AUR
✅ Drop-In✓ In Stock
$5.72 / Unit
View Datasheet →ATMEGA649P-16AUR
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA645P-AUR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.5 / Unit
View Datasheet →ATMEGA645A-AUR
✅ Drop-In✓ In Stock
$4.68 / Unit
View Datasheet →ATMEGA329PA-AUR
✅ Drop-In✓ In Stock
$5.94 / Unit
View Datasheet →ATMEGA649P-AUR Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 64 KB ISP Flash (read-while-write) |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| Maximum CPU Speed | 16 MHz |
| General Purpose I/O | 54/69 lines |
| Working Registers | 32 general purpose |
| LCD Controller | Integrated segment LCD driver |
| Debug Interface | JTAG (on-chip debug, boundary scan) |
| Low Power Technology | picoPower |
| Supply Voltage | 1.8 V to 5.5 V (picoPower family) |
| Operating Temperature | -40C to +85C (industrial, per A-grade suffix) |
| Package | 64TQFP (TQFP-64) |
| Mounting Type | Surface Mount |
| Packing | Tape & Reel (T&R) |
| RoHS / Green | GREEN package |
| Product Status | Active |
ATMEGA649P-AUR 64tqfp (tqfp-64) Pin Configuration Guide
Pin configuration for ATMEGA649P-AUR (64tqfp (tqfp-64) 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 ATMEGA649P-AUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA649P-AUR is suitable for 6 applications: Utility Metering (Energy/Water Meters), Battery-Powered Handheld Instruments, Home Appliance Control Panels, Industrial HMI Front-Ends, Security and Access Control Keypads, Smart Home Sensor Nodes.
Utility Metering (Energy/Water Meters)
The ATMEGA649P-AUR fits electricity, water, and gas meters because the integrated segment LCD controller drives the display glass directly while picoPower sleep modes keep average battery current in the microamp range. A typical topology runs the AVR from a mains-derived or battery supply at 3.3V, pulses from the metrology front-end into a pin-change interrupt, and multiplexes the LCD in power-save mode. The 64KB Flash accommodates metering firmware plus communication stacks, and the 2KB EEPROM stores calibration and billing data through power cycles. The trade-off versus an MCU-plus-external-LCD-driver solution is fewer available I/O while the glass is connected, but BOM cost and board area drop noticeably.
Recommended
Battery-Powered Handheld Instruments
Handheld gauges, testers, and diagnostic tools benefit from the ATMEGA649P-AUR's combination of a directly driven LCD, 1.8V-to-5.5V supply range, and picoPower low-power modes that stretch battery runtime between charges. The device typically sleeps in power-save with an RTC running on a 32kHz crystal, wakes on a key press or timer, and runs measurement code at 16MHz for fast response. SPI interfaces external ADCs or RF modules, while the USART handles PC connectivity. Because the LCD controller is on-chip, the display stays partially visible in low-power states - useful for showing status between measurements. Designers should derate clock speed at low battery voltage per the datasheet speed-versus-voltage curve to guarantee reliable operation near end-of-discharge.
Recommended
Home Appliance Control Panels
White-goods and HVAC front panels use the ATMEGA649P-AUR to combine user-interface segment LCDs, touch or mechanical buttons, and actuator control in a single IC. The 54/69 general purpose I/O lines drive relays, triacs, fans, and buzzer outputs while the LCD controller runs the display glass, removing an external driver stage from the control board. The industrial -40C to +85C temperature rating tolerates kitchen and utility-room environments, and JTAG supports factory debug fixtures. ISP Flash with read-while-write enables production-line firmware updates without socketing parts. The 16MHz AVR core executes single-cycle instructions, giving responsive button debouncing and display refresh even with modest clock rates that also reduce EMI on the appliance's shared ground.
Recommended
Industrial HMI Front-Ends
Machine-mounted operator interfaces leverage the ATMEGA649P-AUR's segment LCD, generous I/O count, and JTAG boundary scan for panel-level manufacturing test. In a typical design the MCU scans keypad matrices, drives status glass, and communicates with a main controller over SPI or USART, while the industrial temperature grade handles cabinet environments from -40C to +85C. The 64KB ISP Flash leaves room for protocol handling plus localized logic, and the 4KB SRAM buffers message queues without external RAM. Boundary-scan via JTAG shortens ICT fixture development on multi-board panels. Compared with a graphics-TFT solution, the segment-LCD approach costs less and draws far less power, at the trade-off of fixed annunciator layouts rather than freely drawn graphics.
Recommended
Security and Access Control Keypads
Door controllers and alarm keypads exploit the ATMEGA649P-AUR's LCD, low sleep current, and EEPROM for credential and configuration storage. The picoPower architecture keeps standby drain low on battery-backup systems, waking on keypad interrupts or WDT periodic checks; the 16MHz core handles DES/AES-lite key checks and RS-485 framing in software. Segment LCDs show arm/disarm status, zone count, and diagnostics without the cost of a graphics display. The 2KB EEPROM retains user codes through power loss with sufficient endurance for frequent code changes, and the 64KB Flash hosts logging plus communication firmware. Developers should budget SRAM carefully - 4KB is adequate for framed protocols but not for TLS-class stacks, which may require an offloaded companion controller.
Recommended
Smart Home Sensor Nodes
Zigbee-adjacent and proprietary-protocol smart-home nodes use the ATMEGA649P-AUR as the sensor controller with a small segment LCD for local indication, a combination few 8-bit MCUs offer in one package. PicoPower sleep modes let a temperature or occupancy node idle in the microamp region and wake on sensor thresholds, transmitting via a SPI radio module. The 1.8V supply floor allows direct two-cell battery operation, avoiding a boost converter, while 54/69 I/O lines cover multiple sensor buses and status LEDs. The 64KB Flash supports OTA-style bootloader code alongside the application, and EEPROM stores calibration and network addresses. The engineering trade-off: commission a bootloader carefully since 4KB SRAM constrains buffer-heavy radio stacks.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA649P-AUR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA649A-AUR | ATMEGA645P-AUR | ATMEGA645A-AUR | ATMEGA329PA-AUR |
|---|---|---|---|---|---|
| Package | TQFP-64 | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same | TQFP-64 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 1 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB |
| Max CPU Speed | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 20 MHz |
| LCD Controller | Yes (integrated segment LCD) | Yes | Yes | Yes | Yes |
| Low Power Process | picoPower (P variant) | Standard (non-P) | picoPower (P variant) | Standard (non-P) | picoPower (P variant) |
Key Differentiators
- picoPower low-sleep-current process (vs ATMEGA649A-AUR)
- Same memory footprint at the same price point with drop-in migration (vs ATMEGA645A-AUR)
- Double the code space of the low-cost LCD alternative (vs ATMEGA329PA-AUR)
Design Notes
To realize the picoPower benefit, actively manage sleep modes: enter power-save or standby rather than idle, disable the analog comparator and unused timer clocks via the PRR register, and use pin-change or watchdog interrupts for wake. The 16MHz maximum frequency is voltage-dependent - verify the datasheet speed-versus-voltage curve before running full speed at low battery voltage. Estimated: a node sleeping 99% of the time in power-save with the LCD in static mode can reduce average current by more than an order of magnitude versus running idle, directly extending coin-cell or Li-SOCl2 battery life in metering products.
Decouple every VCC/AVCC pin pair with 100nF ceramics placed within a few millimeters of the pins, with at least one bulk 4.7-10uF capacitor per supply rail. Keep the LCD driving traces (segment/common lines routed to the glass) reasonably balanced in length and away from the SPI/USART lines to minimize display ghosting and crosstalk. The TQFP-64 thermal pad requirement is modest for this power class, but a solid ground plane under the part improves LCD common-signal quality. Connect the JTAG header (TDI/TDO/TMS/TCK plus reset) on production boards for field debug and boundary-scan ICT.
Do not treat the P variant and non-P variant as electrically identical in power budget calculations: Microchip application note AVR534 states the ATmega649P is an upwards-compatible drop-in for the ATmega649, but some electrical characteristics differ. Re-verify sleep currents and threshold voltages when migrating between ATMEGA649A and ATMEGA649P. Also confirm that port pins shared with LCD segment functions are not double-assigned in your pinout tool - LCD alternate functions vary across the ATmega329/649/6490 family members, and accidental conflicts cause phantom segments.
Compliance Information
Distributor listings describe the part as GREEN (RoHS/lead-free) with Tape & Reel packing. REACH, halogen-free and conflict-minerals status not stated in retrieved data.
