ATMEGA128A-ANR - 8-bit AVR MCU 128KB Flash 16MHz | Microchip
Référence : ATMEGA128A-ANR ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $9.79 | $9,79 |
| 10 | $9.31 | $93,10 |
| 100 | $8.82 | $882,00 |
| 500 | $8.38 | $4 190,00 |
| 1 000 | $7.96 | $7 960,00 |
ATMEGA128A-ANR Présentation
An 8-bit AVR microcontroller is a single-chip processor based on the AVR enhanced RISC architecture, in which most instructions execute in a single clock cycle, delivering throughput close to 1 MIPS per MHz. MCUs of this class sit at the core of embedded systems, combining processor, non-volatile program memory, SRAM data memory, EEPROM, timers, communication peripherals, and analog-to-digital conversion in one package within the broader power-management and control hierarchy of a system.
Key differentiating features of the ATMEGA128A include read-while-write flash capability for in-system self-programming, 4KB of EEPROM for data retention, 4KB of internal SRAM, 32 general-purpose working registers, a real-time counter, four flexible timer/counters with compare modes and PWM, and two USARTs for serial communication. The AVR architecture executes 135 powerful instructions, most in a single clock cycle, giving it strong code density and deterministic real-time behavior.
Technically, the ATMEGA128A is fabricated in a low-power CMOS process and provides a byte-addressable external memory interface (ports PA through PC serve as AD0-AD15 with WR/RD/ALE control), an 8-channel 10-bit ADC, byte-oriented Two-Wire Interface (I2C-compatible), SPI, and a JTAG interface for on-chip debugging and boundary scan. It is 100% pin compatible with the ATmega103 and can replace it on existing PCBs using the M103C compatibility fuse.
Typical applications include industrial automation and control panels, building and HVAC controllers, instrumentation and data loggers, motor control, and legacy ATmega103/ATmega128 designs requiring a second source or extended availability. The large 128KB flash accommodates substantial firmware including protocol stacks and HMI code.
A key design consideration: the -ANR suffix denotes the TQFP 14x14 mm package with tape-and-reel delivery; verify operating voltage range against clock frequency, as maximum rated speed drops at lower VCC in the AVR family.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in the manufacturer datasheet.
Alternatives de remplacement direct pour ATMEGA128A-ANR — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec ATMEGA128A-ANR (même facteur de forme et même empreinte) — différant par Timers/Counters, Package, RoHS Status, Flash Memory, ADC.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
ATMEGA128-16MUR
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$8.4 / unité
Voir la fiche technique →ATMEGA128-16AN
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$7.44 / unité
Voir la fiche technique →ATMEGA128-16AI
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$5.9 / unité
Voir la fiche technique →ATMEGA1281-16MUR
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$8.78 / unité
Voir la fiche technique →ATMEGA1281V-8MUR
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$4.02 / unité
Voir la fiche technique →ATMEGA128A-ANR Valeurs maximales et caractéristiques électriques
| Core Architecture | AVR 8-bit RISC |
| Fréquence d'horloge maximale | 16 MHz |
| Flash Memory | 128 KB (64K x 16) |
| EEPROM | 4 KB |
| SRAM | 4 KB |
| General Purpose I/O | 53 I/O lines |
| Working Registers | 32 general purpose |
| Instructions | 135 instructions, most single-cycle |
| Timer/Counters | 4 flexible timer/counters |
| USART | 2 |
| ADC | 8-channel 10-bit |
| Interfaces | SPI, TWI (I2C-compatible), JTAG |
| External Memory Interface | Yes (WR, RD, ALE) |
| Boîtier | 64-TQFP (14x14 mm) |
| Type de montage | Surface Mount |
| Pin Compatibility | 100% compatible with ATmega103 |
| Statut RoHS | Green (per Mouser) |
Configuration des broches de ATMEGA128A-ANR
| Broche 1 | PEN — Programming Enable (low during power-on for programming) |
| Broche 2 | PE0 (RXD0/PDI) — USART0 receive / programming data in |
| Broche 3 | PE1 (TXD0/PDO) — USART0 transmit / programming data out |
| Broche 4 | PE2 (XCK0/AIN0) — USART0 clock / analog comparator input 0 |
| Broche 5 | PE3 (OC3A/AIN1) — Timer3 output compare A / comparator input 1 |
| Broche 6 | PE4 (OC3B/INT4) — Timer3 output compare B / external interrupt 4 |
| Broche 7 | PE5 (OC3C/INT5) — Timer3 output compare C / external interrupt 5 |
| Broche 8 | PE6 (T3/INT6) — Timer3 clock input / external interrupt 6 |
| Broche 9 | PE7 (ICP3/INT7) — Timer3 input capture / external interrupt 7 |
| Broche 10 | PB0 (SS) — Port B0 / SPI slave select |
| Broche 11 | PB1 (SCK) — Port B1 / SPI clock |
| Broche 12 | PB2 (MOSI) — Port B2 / SPI master data out |
| Broche 13 | PB3 (MISO) — Port B3 / SPI master data in |
| Broche 14 | PB4 (OC2/PWM) — Port B4 / Timer2 output compare |
| Broche 15 | PB5 (OC1A) — Port B5 / Timer1 output compare A |
| Broche 16 | PB6 (OC1B) — Port B6 / Timer1 output compare B |
| Broche 17 | PB7 (OC2A/OC1C) — Port B7 / Timer2/Timer1 output compare |
| Broche 18 | PG3 (TOSC2) — Port G3 / Timer oscillator output (32kHz crystal) |
| Broche 19 | PG4 (TOSC1) — Port G4 / Timer oscillator input |
| Broche 20 | RESET — Reset input (active low) |
| Broche 21 | VCC — Digital supply voltage |
| Broche 22 | GND — Ground |
| Broche 23 | XTAL2 — Main oscillator output |
| Broche 24 | XTAL1 — Main oscillator input / external clock |
| Broche 25 | PD0 (RXD1/SCL) — USART1 receive / TWI clock |
| Broche 26 | PD1 (TXD1/SDA) — USART1 transmit / TWI data |
| Broche 27 | PD2 (RXD1/INT2) — Port D2 / external interrupt 2 |
| Broche 28 | PD3 (TXD1/INT3) — Port D3 / external interrupt 3 |
| Broche 29 | PD4 (ICP1) — Port D4 / Timer1 input capture |
| Broche 30 | PD5 (XCK1) — Port D5 / USART1 external clock |
| Broche 31 | PD6 (T1) — Port D6 / Timer1 external clock input |
| Broche 32 | PD7 (T2) — Port D7 / Timer2 external clock input |
| Broche 33 | PG0 (WR) — Port G0 / external memory write strobe |
| Broche 34 | PG1 (RD) — Port G1 / external memory read strobe |
| Broche 35 | PC0 (A8/AD8) — Port C0 / external memory address/data bus |
| Broche 36 | PC1 (A9/AD9) — Port C1 / external memory address/data bus |
| Broche 37 | PC2 (A10/AD10) — Port C2 / external memory address/data bus |
| Broche 38 | PC3 (A11/AD11) — Port C3 / external memory address/data bus |
| Broche 39 | PC4 (A12/AD12) — Port C4 / external memory address/data bus |
| Broche 40 | PC5 (A13/AD13) — Port C5 / external memory address/data bus |
| Broche 41 | PC6 (A14/AD14) — Port C6 / external memory address/data bus |
| Broche 42 | PC7 (A15/AD15) — Port C7 / external memory address/data bus |
| Broche 43 | PG2 (ALE) — Port G2 / external memory address latch enable |
| Broche 44 | PA7 (AD7) — Port A7 / external memory address/data bus |
| Broche 45 | PA6 (AD6) — Port A6 / external memory address/data bus |
| Broche 46 | PA5 (AD5) — Port A5 / external memory address/data bus |
| Broche 47 | PA4 (AD4) — Port A4 / external memory address/data bus |
| Broche 48 | PA3 (AD3) — Port A3 / external memory address/data bus |
| Broche 49 | PA2 (AD2) — Port A2 / external memory address/data bus |
| Broche 50 | PA1 (AD1) — Port A1 / external memory address/data bus |
| Broche 51 | PA0 (AD0) — Port A0 / external memory address/data bus |
| Broche 52 | VCC — Digital supply voltage |
| Broche 53 | GND — Ground |
| Broche 54 | PF0 (ADC0) — Port F0 / ADC channel 0 |
| Broche 55 | PF1 (ADC1) — Port F1 / ADC channel 1 |
| Broche 56 | PF2 (ADC2) — Port F2 / ADC channel 2 |
| Broche 57 | PF3 (ADC3) — Port F3 / ADC channel 3 |
| Broche 58 | PF4 (ADC4/TCK) — Port F4 / ADC channel 4 / JTAG test clock |
| Broche 59 | PF5 (ADC5/TMS) — Port F5 / ADC channel 5 / JTAG test mode select |
| Broche 60 | PF6 (ADC6/TDO) — Port F6 / ADC channel 6 / JTAG test data out |
| Broche 61 | PF7 (ADC7/TDI) — Port F7 / ADC channel 7 / JTAG test data in |
| Broche 62 | AREF — ADC analog reference input |
| Broche 63 | GND — Ground |
| Broche 64 | AVCC — ADC supply voltage |
Applications typiques
ATMEGA128A-ANR convient pour 6 applications: Industrial Automation and Control, Legacy ATmega103/ATmega128 Board Maintenance, Instrumentation and Data Logging, Motor Control and Power Conversion, Building Automation and HVAC Controllers, Communication Nodes and Gateways.
Industrial Automation and Control
The ATMEGA128A-ANR fits industrial control panels and PLC-style controllers because its 53 GPIO lines, four timer/counters with PWM, and external memory bus support relay driving, sensor polling, and display interfaces in one chip. The 128KB flash accommodates large ladder-logic interpreters or Modbus protocol stacks, while the two USARTs enable simultaneous RS-485 fieldbus and HMI communication. Its deterministic single-cycle-per-instruction AVR core delivers predictable interrupt latency critical for timing loops. Industrial designs should derate clock versus supply voltage and use the watchdog timer for fault recovery in 24V-panel environments with proper isolation.
Recommandé
Legacy ATmega103/ATmega128 Board Maintenance
The ATMEGA128A-ANR is the sanctioned migration path for end-of-life ATmega103 and ATmega128 designs: per the Microchip datasheet it is 100% pin compatible with ATmega103 and drops onto existing PCBs, with the M103C fuse enabling ATmega103 compatibility mode. This lets manufacturers of long-lifecycle equipment keep producing boards without layout changes while gaining the refined 128A die. Engineers should read the application note 'Replacing ATmega103 by ATmega128A', verify fuse defaults, and re-validate timing-critical code, but the footprint, port map, and package are preserved exactly.
Recommandé
Instrumentation and Data Logging
Battery-powered instruments and data loggers benefit from the ATMEGA128A-ANR's 8-channel 10-bit ADC, 4KB EEPROM for calibration constants and event logs, and AVR power-management sleep modes that cut average current dramatically in duty-cycled sampling. The 128KB flash stores both firmware and lookup tables, and TWI/SPI connect precision converters and RTCs. For logging products, pair the MCU with an external SD or FRAM interface via SPI and use Timer/Counter asynchronous mode with a 32kHz crystal for the real-time counter, keeping timestamp accuracy independent of the main clock.
Recommandé
Motor Control and Power Conversion
With four flexible timer/counters including PWM compare outputs on ports PB and PE, the ATMEGA128A-ANR can drive DC and stepper motor H-bridges and basic BLDC commutation schemes. The ADC monitors current shunts and bus voltage, while the analog comparator inputs (AIN0/AIN1 on port E) support zero-cross detection. Designers should route PWM outputs to gate drivers rather than driving MOSFETs directly, keep ADC sampling synchronized to PWM edges via timer-triggered conversion, and observe that 16MHz execution gives ample loop bandwidth for most low- to mid-power motion-control applications.
Recommandé
Building Automation and HVAC Controllers
HVAC and building controllers use the ATMEGA128A-ANR's large I/O count for zone valves, dampers, and multi-sensor inputs, while TWI (I2C) and SPI connect temperature/humidity sensors and displays. The 128KB flash holds BACnet-lite or proprietary protocol firmware with room for OTA-in-field updates via the read-while-write self-programming bootloader, and the 4KB EEPROM preserves configuration across power cycles. Its availability as a mature, actively manufactured part reduces obsolescence risk for 10-20 year building equipment lifecycles, a key procurement criterion in this sector.
Recommandé
Communication Nodes and Gateways
The two independent USARTs on the ATMEGA128A-ANR make it a natural protocol translator: one port handles RS-485/Modbus field traffic while the other connects to a radio, GSM, or Ethernet module. JTAG supports in-field debugging during commissioning, and SPI/TWI link additional network PHYs or memories. The 128KB flash comfortably hosts dual protocol stacks plus buffers in the 4KB SRAM when the code is written carefully. For gateways, implement ring buffers with the USART receive-complete interrupts and consider the external memory bus if line-speed buffering exceeds on-chip SRAM.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour ATMEGA128A-ANR — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | ATMEGA128-16MUR | ATMEGA128-16AN | ATMEGA1281-16MUR | ATMEGA1281V-8MUR |
|---|---|---|---|---|---|
| Package | 64-TQFP (14x14) | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same | 64-TQFP (14x14) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Architecture | 8-bit AVR RISC | 8-bit AVR RISC | 8-bit AVR RISC | 8-bit AVR RISC | 8-bit AVR RISC |
| Flash Memory | 128 KB | 128 KB | 128 KB | 128 KB | 128 KB |
| Maximum Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 8 MHz |
| SRAM | 4 KB | 4 KB | 4 KB | 8 KB | 8 KB |
| USART Count | 2 | 2 | 2 | 2 | 2 |
| ATmega103 Compatibility Mode | Yes (M103C fuse) | Yes (M103C fuse) | Yes (M103C fuse) | No | No |
Principaux différenciateurs
- ATmega103 compatibility mode via M103C fuse (vs ATMEGA1281-16MUR)
- Newer refined die vs original ATmega128 (vs ATMEGA128-16MUR)
- Full-speed 16MHz rating (vs ATMEGA1281V-8MUR)
- Trade-off: less SRAM than newer family members (vs ATMEGA1281-16MUR)
Notes de conception
Estimated: in the AVR mega family, the guaranteed maximum operating frequency depends on supply voltage - running a 16MHz crystal at reduced VCC falls outside the datasheet safe-operating region. Consult the 'Maximum Frequency vs. VCC' curve in the Microchip ATmega128A datasheet before finalizing the power tree. Decouple both VCC pins (21, 52) and AVCC (64) with 100nF ceramics placed within 5 mm of the pins, and connect AVCC to VCC through a low-pass LC filter (10uH + 100nF) when ADC accuracy matters.
The 64-TQFP (14x14 mm) has 0.5 mm pitch leads - specify a solder-mask-defined footprint per IPC-SM-782 or Microchip's QFN/TQFP layout guide and keep thermal relief on the center ground lands minimal. Route the ADC input traces on port F away from XTAL and PWM output lines; a ground moat around the analog section measurably improves 10-bit ADC ENOB. Use a solid ground plane on layer 2 and stitch AVCC/GND filtering near pin 63/64.
The JTAGEN fuse is enabled at factory, so pins PF4-PF7 are JTAG pins, not general-purpose I/O, until JTAG is disabled - designs that assume four extra ADC channels (ADC4-ADC7) will fail if the fuse is overlooked. Also, when migrating from ATmega103, the M103C fuse must be programmed deliberately; in default mode register maps differ and legacy code will malfunction. Finally, RESET has no internal power-on-reset hysteresis in compatibility contexts - verify brown-out fuse settings for reliable startup.
Place the main crystal within 10 mm of XTAL1/XTAL2 (pins 24/23) with short ground returns for the load capacitors. If using the asynchronous Timer/Counter RTC feature, the 32kHz crystal connects to TOSC1/TOSC2 (pins 19/18) and needs its own guarded area - keep switching PWM traces at least 5 mm away to avoid jitter in real-time-clock counting.
Informations de conformité
Mouser lists the ATMEGA128A-ANR as 'Green', Microchip's designation for RoHS-compliant lead-free construction. REACH, halogen-free, and conflict-minerals status not stated in retrieved data; confirm via Microchip's product-page environmental documents.