ATMEGA128-16MUR - 8-bit AVR MCU 128KB 16MHz | Microchip
MPN: ATMEGA128-16MUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.68 | $12.68 |
| 10 | $11.41 | $114.10 |
| 100 | $10.15 | $1,015.00 |
| 500 | $9.12 | $4,560.00 |
| 1,000 | $8.4 | $8,400.00 |
ATMEGA128-16MUR Overview
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor that executes most instructions in a single clock cycle, making it a core embedded processing element within the broader power management and control hierarchy of industrial, consumer, and automotive electronics. The AVR family from Microchip is one of the most widely deployed MCU architectures in embedded systems.
Key features include 131 powerful instructions with mostly single-cycle execution delivering up to 16 MIPS throughput at 16 MHz, an 8-channel 10-bit ADC for analog sensing, a JTAG interface for on-chip debugging and boundary scan, two 8-bit and two 16-bit timers with PWM capability, and dual programmable serial USARTs plus SPI and TWI (I2C) interfaces. Six sleep modes allow aggressive power optimization in battery-conscious designs.
Architecturally, the ATmega128 offers full static operation, 64 KB optional external memory space, and a byte-oriented two-wire serial interface. The 128 KB flash supports 10,000 write/erase cycles, the EEPROM supports 100,000 cycles, and ISP (In-System Programming) via SPI or boot-loader programming via USART simplifies field updates. JTAG provides hardware breakpoint and single-observability debugging.
Typical applications include industrial automation control, sensor data acquisition using the 10-bit ADC, embedded motor and actuator control with hardware PWM, and legacy ATmega103 designs, since the ATmega128 is 100% pin compatible with the ATmega103 and provides an ATmega103 compatibility mode.
A key design consideration is supply voltage: the -16MUR speed grade requires 4.5 V to 5.5 V for 16 MHz operation; for 3 V designs, use the 8 MHz ATmega128V variants instead. Decouple the multiple VCC/GND pin pairs with 0.1 uF ceramics.
This page synthesizes distributor pricing, drop-in alternatives, full 64-pin pinout, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for ATMEGA128-16MUR 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 ATMEGA128-16MUR (same form factor and footprint) β differing in ADC Channels, Package, Supply Voltage Range, Throughput, Timers/Counters.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA128A-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA128A-MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$5.2 / Unit
View Datasheet βATMEGA1281-16MUR
β Drop-Inβ In Stock
$8.78 / Unit
View Datasheet βATMEGA64A-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA128-16MUR Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Core Size | 8-bit |
| Maximum Clock Frequency | 16 MHz |
| Flash Memory | 128 KB (64K x 16) |
| SRAM | 4 KB |
| EEPROM | 4 KB |
| Supply Voltage Range | 4.5 V to 5.5 V |
| ADC Channels | 8 channels |
| ADC Resolution | 10-bit |
| Timers/Counters | 2 x 8-bit, 2 x 16-bit |
| PWM Channels | Yes (hardware PWM) |
| Communication Interfaces | 2 x USART, SPI, TWI (I2C) |
| JTAG Debug | Yes (on-chip debug and boundary scan) |
| I/O Pins | 53 |
| External Memory Support | Up to 64 KB |
| Sleep Modes | 6 |
| Package | 64-VFQFN (9x9 mm) exposed pad |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Throughput | Up to 16 MIPS |
ATMEGA128-16MUR Pin Configuration
| Pin 1 | PE0 (RXD0/PDI) β Port E bit 0 / USART0 receive |
| Pin 2 | PE1 (TXD0/PDO) β Port E bit 1 / USART0 transmit |
| Pin 3 | PE2 (XCK0/AIN0) β Port E bit 2 / USART0 clock / Analog comparator input 0 |
| Pin 4 | PE3 (OC3A/AIN1) β Port E bit 3 / Timer3 output compare A / Analog comparator input 1 |
| Pin 5 | PE4 (OC3B/INT4) β Port E bit 4 / Timer3 output compare B / External interrupt 4 |
| Pin 6 | PE5 (OC3C/INT5) β Port E bit 5 / Timer3 output compare C / External interrupt 5 |
| Pin 7 | PE6 (T3/INT6) β Port E bit 6 / Timer3 clock input / External interrupt 6 |
| Pin 8 | PE7 (ICP3/INT7) β Port E bit 7 / Timer3 input capture / External interrupt 7 |
| Pin 9 | VCC β Digital supply voltage |
| Pin 10 | GND β Ground |
| Pin 11 | PG0 (WR) β Port G bit 0 / External memory write strobe |
| Pin 12 | PG1 (RD) β Port G bit 1 / External memory read strobe |
| Pin 13 | PC0 (A8) β Port C bit 0 / External memory address line 8 |
| Pin 14 | PC1 (A9) β Port C bit 1 / External memory address line 9 |
| Pin 15 | PC2 (A10) β Port C bit 2 / External memory address line 10 |
| Pin 16 | PC3 (A11) β Port C bit 3 / External memory address line 11 |
| Pin 17 | PC4 (A12) β Port C bit 4 / External memory address line 12 |
| Pin 18 | PC5 (A13) β Port C bit 5 / External memory address line 13 |
| Pin 19 | PC6 (A14) β Port C bit 6 / External memory address line 14 |
| Pin 20 | PC7 (A15) β Port C bit 7 / External memory address line 15 |
| Pin 21 | PG2 (ALE) β Port G bit 2 / External memory address latch enable |
| Pin 22 | VCC β Digital supply voltage |
| Pin 23 | GND β Ground |
| Pin 24 | VCC β Digital supply voltage |
| Pin 25 | GND β Ground |
| Pin 26 | PB0 (SS) β Port B bit 0 / SPI slave select |
| Pin 27 | PB1 (SCK) β Port B bit 1 / SPI serial clock |
| Pin 28 | PB2 (MOSI) β Port B bit 2 / SPI master output |
| Pin 29 | PB3 (MISO) β Port B bit 3 / SPI master input |
| Pin 30 | PB4 (OC0/PWM0) β Port B bit 4 / Timer0 output compare |
| Pin 31 | PB5 (OC1A) β Port B bit 5 / Timer1 output compare A |
| Pin 32 | PB6 (OC1B) β Port B bit 6 / Timer1 output compare B |
| Pin 33 | PB7 (OC2/OC1C) β Port B bit 7 / Timer2 output compare / Timer1 output compare C |
| Pin 34 | PF0 (ADC0) β Port F bit 0 / ADC input 0 |
| Pin 35 | PF1 (ADC1) β Port F bit 1 / ADC input 1 |
| Pin 36 | PF2 (ADC2) β Port F bit 2 / ADC input 2 |
| Pin 37 | PF3 (ADC3) β Port F bit 3 / ADC input 3 |
| Pin 38 | PF4 (ADC4/TCK) β Port F bit 4 / ADC input 4 / JTAG test clock |
| Pin 39 | PF5 (ADC5/TMS) β Port F bit 5 / ADC input 5 / JTAG test mode select |
| Pin 40 | PF6 (ADC6/TDO) β Port F bit 6 / ADC input 6 / JTAG test data output |
| Pin 41 | PF7 (ADC7/TDI) β Port F bit 7 / ADC input 7 / JTAG test data input |
| Pin 42 | AREF β ADC reference voltage |
| Pin 43 | GND β Ground |
| Pin 44 | AVCC β Analog supply for ADC |
| Pin 45 | PA0 (AD0) β Port A bit 0 / External memory data/address line 0 |
| Pin 46 | PA1 (AD1) β Port A bit 1 / External memory data/address line 1 |
| Pin 47 | PA2 (AD2) β Port A bit 2 / External memory data/address line 2 |
| Pin 48 | PA3 (AD3) β Port A bit 3 / External memory data/address line 3 |
| Pin 49 | PA4 (AD4) β Port A bit 4 / External memory data/address line 4 |
| Pin 50 | PA5 (AD5) β Port A bit 5 / External memory data/address line 5 |
| Pin 51 | PA6 (AD6) β Port A bit 6 / External memory data/address line 6 |
| Pin 52 | PA7 (AD7) β Port A bit 7 / External memory data/address line 7 |
| Pin 53 | PG3 (TOSC2) β Port G bit 3 / Timer oscillator output |
| Pin 54 | PG4 (TOSC1) β Port G bit 4 / Timer oscillator input |
| Pin 55 | RESET β Reset input (active low) |
| Pin 56 | VCC β Digital supply voltage |
| Pin 57 | GND β Ground |
| Pin 58 | XTAL2 β Crystal oscillator output |
| Pin 59 | XTAL1 β Crystal oscillator input |
| Pin 60 | PD0 (SCL/INT0) β Port D bit 0 / TWI clock / External interrupt 0 |
| Pin 61 | PD1 (SDA/INT1) β Port D bit 1 / TWI data / External interrupt 1 |
| Pin 62 | PD2 (TXD1/INT2) β Port D bit 2 / USART1 transmit / External interrupt 2 |
| Pin 63 | PD3 (RXD1/INT3) β Port D bit 3 / USART1 receive / External interrupt 3 |
| Pin 64 | PD4 (ICP1) β Port D bit 4 / Timer1 input capture |
Typical Applications
ATMEGA128-16MUR is suitable for 6 applications: Industrial Automation Control, Analog Sensor Data Acquisition, Motor Control with PWM, Embedded Communication Nodes, ATmega103 Legacy Migration, Consumer and Battery-Powered Devices.
Industrial Automation Control
The ATMEGA128-16MUR suits industrial controllers because its 53 I/O lines, dual USARTs, and hardware PWM let one MCU drive relays, read sensors, and communicate on RS-485 networks simultaneously. The 16 MHz AVR core executes most of its 131 instructions in a single cycle, delivering 16 MIPS for deterministic control loops. Its 128 KB flash accommodates large ladder-logic interpreters or communication stacks, while the 4 KB EEPROM stores calibration data and counters that survive power loss. JTAG debugging shortens commissioning cycles on factory floors. Wide 4.5 V to 5.5 V tolerance tolerates noisy industrial 5 V rails with regulator sag.
Recommended
Analog Sensor Data Acquisition
The 8-channel 10-bit ADC of the ATMEGA128-16MUR directly digitizes thermistors, potentiometers, and pressure sensors without an external converter. With AREF and AVCC pins available for a precision reference, achievable resolution is roughly 5 mV per LSB on a 5 V rail, sufficient for threshold monitoring and trend logging. Six sleep modes allow duty-cycled sampling that stretches battery or energy-harvesting budgets, waking via interrupt to burst-sample and transmit over TWI or SPI. The 4 KB EEPROM locally stores calibration coefficients per channel. This removes a dedicated ADC chip from the BOM in cost-sensitive multi-sensor nodes.
Recommended
Motor Control with PWM
With two 8-bit and two 16-bit timers generating hardware PWM, the ATMEGA128-16MUR drives DC and stepper motor drivers without CPU-intensive software timing. The 16 MHz clock yields PWM resolutions up to 16-bit at low frequencies or fast 20 kHz control frequencies for inaudible motor operation. External memory bus signals (ALE, RD, WR on Ports C/G) enable expansion for encoders or display interfaces, and input-capture pins measure encoder feedback precisely. The 5 V supply directly interfaces classic H-bridge driver logic thresholds. JTAG allows single-stepping commutation firmware during drive bring-up and fault analysis.
Recommended
Embedded Communication Nodes
The ATMEGA128-16MUR integrates two USARTs plus SPI and TWI, allowing a single node to bridge a field bus, a local peripheral bus, and a debugging console concurrently. At 16 MHz, USART rates up to 1 Mbps support Modbus and proprietary protocols, while SPI clocks to fosc/2 (8 MHz) for fast displays or flash logging. The 128 KB flash stores protocol stacks and buffering code with room for boot-loader-based field updates over the serial link, extending deployed product life. This makes the part common in gateways, metering heads, and legacy telemetry equipment still produced today.
Recommended
ATmega103 Legacy Migration
The ATmega128 is 100% pin compatible with the ATmega103 and offers an ATmega103 compatibility mode via fuse setting, which preserves the original register map and memory map for code reuse. Boards designed around the ATmega103 can adopt the ATMEGA128-16MUR without PCB respin, immediately gaining 128 KB flash (versus 128 KB on ATmega103 but with extended features), extra timers, TWI, and dual USARTs when running in native mode. This makes it the standard upgrade path for maintaining discontinued ATmega103-based industrial and medical devices while preserving firmware investment and approvals.
Recommended
Consumer and Battery-Powered Devices
Although the -16MUR grade targets 5 V systems, the ATMEGA128 architecture's six sleep modes - including power-down at microamp levels and idle modes with timers running - let designers aggressively duty-cycle consumer appliances, chargers, and accessories. Idle mode keeps the ADC and one USART alive for wake-on-event designs; power-save wakes on timer for periodic tasks. Combined with in-system boot-loader programming via the USART, products can receive firmware updates in the field from a 5 V USB-style supply. Cost-sensitive volume products benefit from the mature, multi-source-supported AVR toolchain.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA128-16MUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA128A-MU | ATMEGA128A-MUR | ATMEGA1281-16MUR | ATMEGA64A-MU |
|---|---|---|---|---|---|
| Package | 64-QFN (9x9 mm) MLF | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same | 64-QFN (9x9 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 128 KB | 128 KB | 128 KB | 128 KB | 64 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 8 KB | 2 KB |
| EEPROM | 4 KB | 4 KB | 4 KB | 4 KB | 2 KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Pinout Compatibility | Reference (ATmega128 pinout) | Pin-to-pin identical | Pin-to-pin identical | Same pin count, partial function differences | Pin-to-pin identical |
| Architecture / Family | 8-bit AVR ATmega128 | 8-bit AVR ATmega128A (die-shrink) | 8-bit AVR ATmega128A (die-shrink) | 8-bit AVR ATmega1281 | 8-bit AVR ATmega64A |
Key Differentiators
- Maximum code space in the ATmega64/128 QFN pin-compatible family (vs ATMEGA64A-MU)
- Drop-in die-shrink continuity path (vs ATMEGA128A-MU)
- 100% ATmega103 pin compatibility with compatibility mode (vs ATMEGA1281-16MUR)
Design Notes
Decouple every VCC pin pair individually: the 64-QFN ATMEGA128-16MUR has multiple VCC/GND pairs (pins 9/10, 22/23, 24/25, 56/57). Place a 0.1 uF ceramic capacitor within 2 mm of each VCC pin and add a 10 uF bulk capacitor near the supply entry. Connect AVCC (pin 44) to VCC through a low-pass LC filter (10 uH + 0.1 uF) when ADC accuracy matters, and tie AREF to a clean reference with a 100 nF capacitor when using the external reference mode.
The exposed pad on the 64-QFN (9x9 mm) package should be soldered to a grounded thermal array on the PCB. It provides the primary GND connection and improves heat spreading; a poorly soldered exposed pad is a common cause of intermittent resets and degraded ground integrity. Use an array of 4x4 to 5x5 vias under the pad filled or tented per IPC guidance, connected to the internal ground plane.
Three frequent design errors: (1) running at 16 MHz below 4.5 V violates the speed/voltage derating curve - use the V speed grade parts for 3 V operation; (2) forgetting that PF4-PF7 are shared with JTAG - if JTAG is enabled by default, those ADC channels and I/O are unavailable; disable JTAGEN via fuse or use the JTD bit for ADC-heavy designs; (3) in ATmega103 compatibility mode, extended features (TWI, second USART, additional timers) are inaccessible - verify the M103C fuse is cleared for native mode.
Keep XTAL1/XTAL2 crystal traces short (under 10 mm) and guarded by ground, with load capacitors chosen per the crystal specification (typically 12-22 pF for 16 MHz fundamental crystals). For external memory bus operation at full 16 MHz, match trace lengths on the multiplexed AD0-AD7 bus and add series termination (22-33 ohm) on ALE to control ringing on expansion designs.
Compliance Information
RoHS compliance and lead-free status per distributor listings for the ATMEGA128-16MUR. REACH, halogen-free, and conflict-minerals declarations should be confirmed from Microchip's certificate of conformance for the specific date code.
