ATMEGA168PA-MNR - AVR 8-Bit MCU 16KB 20MHz VQFN-32 | Microchip
MPN: ATMEGA168PA-MNR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.1 | $2.10 |
| 10 | $1.89 | $18.90 |
| 100 | $1.68 | $168.00 |
| 500 | $1.51 | $755.00 |
| 1,000 | $1.36 | $1,360.00 |
ATMEGA168PA-MNR Overview
An 8-bit AVR microcontroller is a Harvard-architecture RISC processor that combines program FLASH, data SRAM, and EEPROM on a single die, forming the core of a full system-on-chip power management and embedded control solution. The AVR family pioneered single-cycle instruction execution, making ATmega devices a de facto standard for cost-sensitive embedded control from hobby platforms to industrial products.
Key features of the ATMEGA168PA-MNR include 23 general-purpose I/O lines, 32 general-purpose working registers, three flexible timer/counters with compare modes (two 8-bit, one 16-bit), a 10-bit ADC with up to 8 channels, and serial peripherals including USART, SPI, and two-wire I2C interfaces. The picoPower technology delivers very low sleep-mode currents, extending battery life in portable designs. On-chip debug via debugWIRE and In-Circuit Serial Programming (ICSP) simplify development with tools such as MPLAB SNAP and AVR ISP MKII.
The advanced RISC architecture provides 131 powerful instructions, hardware multiply, and read-while-write FLASH operation. Brown-out detection, power-on reset, an internal calibrated 8 MHz RC oscillator, and a watchdog timer reduce external component count and improve system robustness. Six sleep modes, including Idle, ADC Noise Reduction, Power-save, and Power-down, allow fine-grained energy optimization down to the microamp range.
Typical applications include battery-powered consumer devices, industrial sensor nodes, motor and LED control, HVAC and home-automation products, and low-cost data loggers where the 16 KB FLASH / 1 KB SRAM balance is sufficient and the compact 5x5 mm VQFN footprint saves PCB area.
A key design consideration: the -MNR suffix indicates Tape and Reel packaging and the lead-free/RoHS MLF package, whose exposed die pad must be soldered to a grounded copper pour for both mechanical retention and thermal performance; VCC/GND decoupling capacitors should be placed within 2 mm of the pads.
This page adds value beyond the manufacturer datasheet by synthesizing distributor pricing tiers, drop-in same-footprint alternatives across the ATmega48/88/168/328 families, and practical PCB and power-design notes in one citation-ready reference.
Drop-in alternatives for ATMEGA168PA-MNR 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 ATMEGA168PA-MNR (same form factor and footprint) β differing in Package, Communication Interfaces, Core Processor, Flash Memory, Operating Temperature.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA168A-MU
β Drop-Inβ In Stock
$1.38 / Unit
View Datasheet βATMEGA168PA-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.72 / Unit
View Datasheet βATMEGA328P-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.28 / Unit
View Datasheet βATMEGA328-MU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA88PA-MU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA48PA-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA328PB-MNR
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA168PA-MNR Maximum Ratings & Electrical Characteristics
| Core Processor | AVR |
| Core Size | 8-Bit |
| Speed | 20 MHz |
| Flash Memory | 16 KB (8K x 16) |
| EEPROM | 512 B |
| SRAM | 1 KB |
| Operating Temperature | -40C to +105C |
| Number of I/O | 23 |
| Timers/Counters | 3 (2 x 8-bit, 1 x 16-bit) |
| ADC Resolution | 10-bit |
| ADC Channels | 8 |
| Communication Interfaces | USART, SPI, I2C (TWI) |
| Package | 32-VQFN (5x5 mm) MLF, exposed pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (MNR suffix) |
| Programming / Debug | ICSP, debugWIRE |
ATMEGA168PA-MNR Pin Configuration
| Pin 1 | PD3 β Port D bit 3 / INT1 external interrupt |
| Pin 2 | PD4 β Port D bit 4 / Timer0 T0 input |
| Pin 3 | GND β Ground |
| Pin 4 | VCC β Digital supply voltage |
| Pin 5 | GND β Ground |
| Pin 6 | VCC β Digital supply voltage |
| Pin 7 | PB6 β Port B bit 6 / XTAL1 clock input |
| Pin 8 | PB7 β Port B bit 7 / XTAL2 clock output |
| Pin 9 | PD5 β Port D bit 5 / Timer0 T1 input |
| Pin 10 | PD6 β Port D bit 6 / Analog comparator AIN0 |
| Pin 11 | PD7 β Port D bit 7 / Analog comparator AIN1 |
| Pin 12 | PB0 β Port B bit 0 / XCK, T0 |
| Pin 13 | PB1 β Port B bit 1 / T1, OC1A |
| Pin 14 | PB2 β Port B bit 2 / SS, OC1B |
| Pin 15 | PB3 β Port B bit 3 / MOSI, OC2A |
| Pin 16 | PB4 β Port B bit 4 / MISO |
| Pin 17 | PB5 β Port B bit 5 / SCK |
| Pin 18 | AVCC β Analog supply voltage for ADC |
| Pin 19 | ADC6 β ADC input channel 6 |
| Pin 20 | AREF β Analog reference voltage |
| Pin 21 | GND β Ground |
| Pin 22 | ADC7 β ADC input channel 7 |
| Pin 23 | PC0 β Port C bit 0 / ADC0 |
| Pin 24 | PC1 β Port C bit 1 / ADC1 |
| Pin 25 | PC2 β Port C bit 2 / ADC2 |
| Pin 26 | PC3 β Port C bit 3 / ADC3 |
| Pin 27 | PC4 β Port C bit 4 / ADC4, SDA |
| Pin 28 | PC5 β Port C bit 5 / ADC5, SCL |
| Pin 29 | PC6 β Port C bit 6 / RESET (active low) |
| Pin 30 | PD0 β Port D bit 0 / USART RXD |
| Pin 31 | PD1 β Port D bit 1 / USART TXD |
| Pin 32 | PD2 β Port D bit 2 / INT0 external interrupt |
Typical Applications
ATMEGA168PA-MNR is suitable for 6 applications: Battery-Powered Sensor Nodes, Industrial Control and Automation, Consumer Appliances and Home Automation, Motor Control and LED Lighting, Automotive Body and Convenience Modules, Hobby, Education, and Rapid Prototyping.
Battery-Powered Sensor Nodes
The ATMEGA168PA-MNR is a strong fit for battery-powered sensor nodes because its picoPower technology offers six sleep modes, including Power-down at microamp-level current, which directly translates to multi-year coin-cell life. Its 16 KB FLASH accommodates wireless protocol stacks and calibration code, while 1 KB SRAM buffers sensor data. Typical designs pair the MCU with an RF transceiver over SPI and sample the ADC at 10-bit resolution. By waking on pin-change or watchdog interrupt, duty-cycled operation is achieved without an external wake timer, and the internal 8 MHz oscillator eliminates crystal cost in non-timing-critical nodes.
Recommended
Industrial Control and Automation
In industrial control panels and automation modules, the ATMEGA168PA-MNR's -40C to +105C operating range, brown-out detector, and watchdog timer provide the robustness required on noisy factory floors. The 16-bit timer with compare modes generates PWM for motor and heater control, while the USART links to RS-485 transceivers for Modbus-style networks. With 23 GPIO lines, it directly drives relays and opto-isolated inputs. Its VQFN-32 footprint keeps control-board area small, and the wide Flash headroom (16 KB) leaves space for field-updatable firmware delivered over the serial bootloader.
Recommended
Consumer Appliances and Home Automation
Consumer appliances such as coffee machines, fans, and smart-home controllers benefit from the ATMEGA168PA-MNR's low cost, single-cycle RISC core at 20 MHz, and integrated capacitive-touch-capable I/O. The 10-bit ADC reads NTC thermistors and user potentiometers, while TWI (I2C) interfaces OLED display drivers. picoPower sleep modes meet standby-energy regulations for appliances that idle most of the day. Because the device programs in-system via ICSP, manufacturers can flash final firmware on the assembly line. The 5x5 mm VQFN fits compact appliance PCBs behind front panels where space is at a premium.
Recommended
Motor Control and LED Lighting
For small motor control and LED lighting drivers, the ATMEGA168PA-MNR provides two 8-bit timers and one 16-bit timer with compare outputs, enabling multi-channel PWM at up to 8-bit resolution for dimming and speed control. The hardware ADC synchronizes current-sense feedback for closed-loop regulation, and the 20 MHz clock gives sufficient loop bandwidth for fan and pump control. Operating to +105C ambient suits enclosed luminaires. The ADC Noise Reduction sleep mode reduces measurement jitter during current sampling, and the interrupt-on-pin-change feature handles zero-cross detection for AC phase-dimming applications without additional components.
Recommended
Automotive Body and Convenience Modules
While the standard ATMEGA168PA-MNR is not the AEC-Q100 qualified variant, its architecture underpins automotive-grade siblings, and the device itself is used in non-safety vehicle convenience electronics such as seat-position memories, interior lighting, and aftermarket accessories within cabin temperature limits. The 16 KB FLASH stores seat-motor sequences and LIN frames, the USART connects to LIN transceivers for the vehicle network, and the 10-bit ADC reads position potentiometers. Designers needing automotive qualification should cross to the ATmega168PA-AUR graded part, which shares the same die and pinout for easy migration.
Recommended
Hobby, Education, and Rapid Prototyping
The ATMEGA168PA-MNR is the silicon behind popular hobby and educational platforms (the pre-2010 Arduino family used the ATmega168), making it ideal for rapid prototyping and STEM education. A vast ecosystem of bootloaders, libraries, and programmers supports it; ICSP programming works with inexpensive USBasp and MPLAB SNAP tools. The 32 general-purpose registers and 131 single-cycle instructions make assembly teaching straightforward, while C compilers such as avr-gcc are mature. Because the ATmega48/88/168/328 family shares one VQFN-32 pinout, prototypes built on the 168PA upgrade to 32 KB ATmega328P for release firmware without any board respin.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA168PA-MNR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA168A-MU | ATMEGA168PA-MU | ATMEGA328P-MU | ATMEGA88PA-MU | ATMEGA48PA-MU | ATMEGA328PB-MNR |
|---|---|---|---|---|---|---|---|
| Package | 32-VQFN (5x5 mm) | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same | 32-VQFN (5x5 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB | 16 KB | 16 KB | 32 KB | 8 KB | 4 KB | 32 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 2 KB | 1 KB | 256 B | 2 KB |
| EEPROM | 512 B | 512 B | 512 B | 1 KB | 64 B | 64 B | 1 KB |
| Max Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| picoPower Technology | Yes | No | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- picoPower low-sleep-current technology (vs ATMEGA168A-MU)
- Lowest cost with adequate code space (vs ATMEGA328P-MU)
- Room to grow within one footprint (vs ATMEGA48PA-MU)
Design Notes
The 32-pad VQFN (MLF) package has an exposed die pad on the bottom that must be connected to ground. Design the PCB land pattern with a central thermal pad of roughly 3.5 x 3.5 mm tied to the GND plane via an array of 9 to 16 vias (0.3 mm diameter) for heat spreading and mechanical reliability. Extend PCB pads 0.3 to 0.5 mm beyond the package edge for solder fillet inspection, and stencil-print the center pad with about 50% coverage to avoid paste voids.
Decouple each VCC pin (pins 4 and 6) and AVCC (pin 18) with 100 nF ceramic capacitors placed within 2 mm of the pads, plus a single 10 uF bulk capacitor near the device. AVCC must be connected to VCC even if the ADC is unused - leaving it floating causes undefined ADC behavior. Tie AREF (pin 20) to GND through 100 nF when using internal references; never drive AREF with an external voltage while an internal reference is selected.
PC6 is RESET by default and is not usable as general I/O unless the RSTDISBL fuse is programmed - which permanently disables ISP programming and should be avoided. Enabling debugWIRE by programming the DWEN fuse requires the device to run from a stable clock; recovery from an accidental DWEN/SPIEN fuse lockout may require a high-voltage programmer. Also verify clock-source fuses: shipping default is the internal 8 MHz oscillator with CKDIV8 enabled, so a fresh device starts at only 1 MHz.
Keep the crystal (if used on PB6/PB7) within 5 mm of the device with short ground guards around the 12 to 22 pF load capacitors. Route analog ADC inputs (PC0-PC5, ADC6/ADC7) away from USART and SPI switching lines; use the ADC Noise Reduction sleep mode and a series 1k resistor plus 100 nF filter on high-impedance sensors to preserve 10-bit accuracy. Analog ground return should tie to the die-pad ground at a single point to avoid digital switching noise modulating ADC readings.
Compliance Information
The MNR suffix indicates lead-free (NiPdAu finish) MLF packaging; DigiKey lists the part as RoHS-compliant. REACH, halogen-free and conflict-minerals status not stated in provided data.
