ATMEGA640-16CUR - 8-Bit AVR MCU 64KB 16MHz 100-CBGA | Microchip
MPN: ATMEGA640-16CUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.5 | $10.50 |
| 10 | $9.45 | $94.50 |
| 100 | $8.4 | $840.00 |
| 500 | $7.56 | $3,780.00 |
| 1,000 | $6.72 | $6,720.00 |
ATMEGA640-16CUR Overview
An 8-bit AVR microcontroller is a reduced-instruction-set (RISC) single-chip computer that integrates program Flash, data SRAM, EEPROM, timers, serial interfaces, and an ADC on one die. Within the power-management-and-control hierarchy of embedded systems, the AVR ATmega family sits in the general-purpose microcontroller class, alongside families such as PIC and STM8, and is programmed through In-System Programming (ISP) and debugged via In-Circuit Serial Programming (ICSP).
Key features include 86 general-purpose I/O lines, up to four programmable serial USARTs, a master/slave SPI interface, a byte-oriented 2-wire serial interface (TWI/I2C-compatible), an 8/16-channel 10-bit ADC, an output-compare modulator, a programmable watchdog timer with a separate on-chip oscillator, and an on-chip analog comparator. The AVR core uses a Harvard architecture with 32 general-purpose working registers directly connected to the ALU, allowing most instructions to execute in a single clock cycle.
The -16 speed grade sustains full 16 MIPS throughput at 16 MHz (5V), while the wide 2.7V to 5.5V operating range supports both battery-powered 3.3V designs and industrial 5V systems. The 64 KB self-programmable Flash enables boot-loader-based field firmware updates, and 4 KB EEPROM retains calibration data through power cycles.
Typical applications include industrial automation controllers, building automation and HVAC boards, test and measurement instrumentation, and legacy ATmega2560-style embedded designs that need a lower-cost 64 KB memory point.
Design consideration: at 16 MHz the device is specified for 4.5V to 5.5V operation; below 4.5V the maximum safe clock frequency decreases, so derate f_MAX versus VCC per the manufacturer datasheet.
This page synthesizes distributor pricing, drop-in alternatives within the same 100-ball CBGA footprint, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA640-16CUR 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 ATMEGA640-16CUR (same form factor and footprint) β differing in ADC, Flash Memory, SRAM, Serial Interfaces, USART.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA1280-16CUR
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$6.25 / Unit
View Datasheet βATMEGA2560-16CUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA1281-16CUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA2561-16CUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA1280-16CU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$12.9 / Unit
View Datasheet βATMEGA640-16CUR Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 64 KB (32K x 16) ISP Flash |
| SRAM | 8 KB (8K x 8) |
| EEPROM | 4 KB |
| Maximum Clock Frequency | 16 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V |
| General Purpose I/O | 86 lines |
| Working Registers | 32 general purpose registers |
| USART | 4 programmable serial USART |
| SPI | Master/Slave SPI serial interface |
| TWI | Byte-oriented 2-wire serial interface |
| ADC | 8/16-channel, 10-bit |
| Analog Comparator | On-chip |
| Watchdog Timer | Programmable, separate on-chip oscillator |
| Package | 100-CBGA (9x9 mm) |
| Mounting Type | Surface Mount |
| Programming / Debug | ISP, ICSP (2 I/O pins + reset) |
| Product Series | AVR ATmega |
ATMEGA640-16CUR 100-cbga (9x9 mm) Pin Configuration Guide
Pin configuration for ATMEGA640-16CUR (100-cbga (9x9 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 ATMEGA640-16CUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA640-16CUR is suitable for 6 applications: Industrial Automation Controllers, Building Automation and HVAC Boards, Test and Measurement Instrumentation, Legacy ATmega2560-Style Embedded Designs, Multi-Channel Communication Gateways, Motor and Power Control Panels.
Industrial Automation Controllers
The ATMEGA640-16CUR fits PLC-lite and machine-control boards because it combines four USARTs, SPI, TWI, and a 10-bit ADC in a single 5V-tolerant AVR core. A controller can talk RS-485 on one USART, a HMI on a second, and a servo or sensor bus on the remaining links while the ADC digitizes analog setpoints. Running at 16 MHz it delivers roughly 16 MIPS, adequate for deterministic polling loops and PID control at millisecond rates. The 2.7V to 5.5V supply range and industrial-grade CU suffix support noisy factory-floor rails, and the 64 KB Flash holds protocol stacks with headroom for OTA boot-loader updates through the self-programmable memory.
Recommended
Building Automation and HVAC Boards
In HVAC and building-management panels, the ATMEGA640-16CUR's 86 GPIO lines drive relays, valves, and LED indicators directly, while its 10-bit ADC reads NTC thermistors and pressure sensors across up to 16 channels. The TWI interface connects RTC and environmental sensors, and the separate on-chip oscillator watchdog provides autonomous recovery from latch-ups on long field wiring. Four USARTs accommodate Modbus RTU, a display, and a service port simultaneously. The 4 KB EEPROM stores setpoints and run-hour counters without external nonvolatile memory, surviving power interruptions common in field installations, and the CBGA package resists thermal cycling stress better than fine-pitch QFP alternatives.
Recommended
Test and Measurement Instrumentation
Bench instruments and data loggers benefit from the ATMEGA640-16CUR's combination of a 10-bit ADC, output-compare modulator, and on-chip analog comparator for threshold-triggered capture. At 16 MHz the AVR core sustains single-cycle ALU operation, giving predictable execution timing for measurement sequencing and timestamping. The 64 KB self-programmable Flash lets firmware store calibration tables in EEPROM and update instrument personalities in the field via boot loader. Four USARTs stream results to a PC, a printer, and a secondary instrument concurrently. The 9x9 mm CBGA keeps the analog section compact, and the 5V operation provides generous noise margin for analog front-ends on shared rails.
Recommended
Legacy ATmega2560-Style Embedded Designs
The ATMEGA640-16CUR is the natural cost-optimization point for designs originally specified around the ATmega2560/1280 family: it shares the same die, pinout, and CBGA-100 footprint, so a PCB designed for ATMEGA2560-16CUR accepts the ATMEGA640-16CUR without rework. Firmware under 64 KB runs unchanged, cutting BOM cost on high-volume legacy boards. Conversely, boards provisioned with the 640 can be upgraded to 128 KB or 256 KB parts if firmware grows. This common-die strategy, documented across the ATmega640/1280/2560 datasheet, is why contract manufacturers often stock the entire family and offer single-footprint second sourcing for long-lifecycle products such as agricultural and marine controllers.
Recommended
Multi-Channel Communication Gateways
Protocol gateways need many independent serial links, and the ATMEGA640-16CUR provides exactly that: four USARTs plus hardware SPI and TWI let a bridge translate between, for example, a fieldbus, a display, and a configuration interface without bit-banging. The 8 KB SRAM buffers multiple message frames and retransmission queues, a resource that smaller ATmega parts exhaust quickly. The 16 MHz clock supports 115.2 kbps on all four USARTs simultaneously with ample CPU margin. Industrial 5V signaling on the GPIO tolerates long cable runs with simple protection, and the programmable watchdog with its own oscillator guarantees recovery if a peer node stalls the firmware.
Recommended
Motor and Power Control Panels
Motor starter and power-panel controllers exploit the ATMEGA640-16CUR's six flexible timer/counters with output-compare and the output-compare modulator to generate PWM for drives and heaters while the 10-bit ADC monitors current shunts and bus voltage. The analog comparator enables fast over-current trip logic independent of the CPU. The 5V industrial supply range rides through sags on control power, and the 86 GPIO handle contactor drives, selector switches, and lamp columns without port expanders. EEPROM retention keeps last-known motor configurations through brownouts. The CBGA's solder-ball interconnects withstand vibration better than fine-pitch leads, improving reliability in pump and compressor enclosures.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA640-16CUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA1280-16CUR | ATMEGA2560-16CUR | ATMEGA1281-16CUR | ATMEGA2561-16CUR |
|---|---|---|---|---|---|
| Package | 100-CBGA (9x9 mm) | 100-CBGA (9x9 mm) - same | 100-CBGA (9x9 mm) - same | 100-CBGA (9x9 mm) - same | 100-CBGA (9x9 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 128 KB | 256 KB | 128 KB | 256 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB |
| EEPROM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| Max Clock | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Supply Voltage | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| GPIO / Port Complement | 86 GPIO (full complement) | 86 GPIO (full complement) | 86 GPIO (full complement) | Reduced (1281 variant) | Reduced (2561 variant) |
| Packaging Option | Tape & Reel (R suffix) | Tape & Reel (R suffix) | Tape & Reel (R suffix) | Tape & Reel (R suffix) | Tape & Reel (R suffix) |
Key Differentiators
- Lowest-cost entry point of the common-die ATmega CBGA family (vs ATMEGA2560-16CUR)
- Full 86-GPIO port complement (vs ATMEGA2561-16CUR)
- Field-upgradeable Flash headroom trade-off (vs ATMEGA1280-16CUR)
Design Notes
Respect the frequency-versus-voltage derating curve: the 16 MHz -16 speed grade is guaranteed only at 4.5V to 5.5V. If your rail is 3.3V, reduce the clock (about 8 MHz maximum) or switch to an appropriate speed grade. Add 100 nF ceramic decoupling on each VCC/AVCC pair plus bulk 10 uF, and keep AVCC tied to VCC through an LC filter when using the ADC so that digital switching noise does not corrupt 10-bit conversions.
The 100-ball CBGA requires a ball-matched land pattern with via-in-pad or dog-bone escape on the inner rows; follow the Microchip recommended footprint in the datasheet package section. Use NSMD pads and control reflow profile per the ball-alloy specification - CBGA parts cannot be hand-reworked easily, so verify first-article X-ray inspection for shorts on the perimeter rows. A solid ground plane under the die improves signal return paths for the four USARTs and SPI bus.
Boot-loader flash start address differs by family member: code compiled for 64 KB will not boot unchanged on an ATMEGA2560 drop-in unless the bootloader section fuses (BOOTSZ) and vector table placement are reconfigured for the larger Flash. Also remember the watchdog uses a separate on-chip oscillator with its own tolerance; do not assume WDT timing equals the 16 MHz system clock. Finally, verify EEPROM write endurance is not consumed by periodic logging - 4 KB EEPROM endurance is finite per cell.
Compliance Information
RoHS/lead-free inferred from the C package code and distributor listings for this suffix. Obtain Microchip's official certificate for REACH, halogen-free, and conflict-minerals declarations.