ATMEGA164PA-MNR - 8-bit AVR MCU 16KB Flash 20MHz | Microchip
MPN: ATMEGA164PA-MNR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.06 | $4.06 |
| 10 | $3.68 | $36.80 |
| 100 | $3.3 | $330.00 |
| 500 | $2.96 | $1,480.00 |
| 1,000 | $2.66 | $2,660.00 |
ATMEGA164PA-MNR Overview
An 8-bit AVR microcontroller is a Harvard-architecture MCU that separates program flash from data SRAM, sitting in the wider hierarchy of microcontrollers under the power-efficient embedded control IC category. The ATmega family is widely used where low standby power, deterministic execution, and mature tooling (AVR GCC, Atmel Studio / MPLAB X) matter more than raw processing throughput.
Key features of the ATMEGA164PA-MNR include 32 general purpose I/O lines, three flexible timer/counters with compare modes and PWM, two USARTs, a byte-oriented Two-Wire (I2C-compatible) serial interface, an 8-channel 10-bit ADC, and a real-time counter with separate oscillator. The picoPower technology enables sub-uA sleep currents, and the device supports ISP and IAP flash programming with read-while-write capability. Operating voltage spans 2.5V/3.3V/5V systems per distributor parametric data, covering both 3.3V and 5V logic designs.
Per Microchip application note AVR527, the ATmega164PA is a functionally identical drop-in replacement for the ATmega164P within the same 44-pin package, differing only in electrical characteristics due to a new manufacturing process - so existing firmware migrates without code changes.
Typical applications include industrial sensor nodes, consumer appliances, battery-powered metering, HVAC control, and hobby/embedded products where a 5V-tolerant 8-bit MCU with on-chip ADC simplifies the BOM.
When designing with this MCU, budget flash carefully: 16 KB holds structured C code well, but floating-point-heavy code or large lookup tables may force a move to the pin-compatible ATmega324PA/644PA/1284P.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA164PA-MNR — 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 ATMEGA164PA-MNR (same form factor and footprint) — differing in Package, Flash Memory, Working Registers, Operating Temperature, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA164P-20MUR
✅ Drop-In✓ In Stock
$1.5 / Unit
View Datasheet →ATMEGA164A-MU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.01 / Unit
View Datasheet →ATMEGA164P-20MQ
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.96 / Unit
View Datasheet →ATMEGA324PA-MU
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA644PA-MU
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA1284P-MUR
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →ATMEGA164PA-MNR Maximum Ratings & Electrical Characteristics
| Core Architecture | AVR enhanced RISC, 8-bit |
| Max Clock Frequency | 20 MHz |
| Flash Memory | 16 KB (8K x 16) ISP flash, read-while-write |
| SRAM | 1 KB |
| EEPROM | 512 B |
| I/O Lines | 32 general purpose I/O |
| Timers | 3 timer/counters with compare modes and PWM |
| USART | 2 |
| Serial Interfaces | Two-Wire (I2C), SPI |
| ADC | 8-channel 10-bit |
| Operating Voltage | 2.5 V / 3.3 V / 5 V |
| Low Power Technology | picoPower |
| Programming | ISP, IAP; debugWire/ICSP via reset line |
| Package | 44-VQFN (7x7 mm) exposed pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (T/R) |
| RoHS Status | Compliant (GRN / green per Mouser) |
| Working Registers | 32 x 8-bit general purpose |
ATMEGA164PA-MNR Pin Configuration
| Pin 1 | VCC — Digital supply voltage |
| Pin 2 | PA0 (ADC0) — Port A bit 0 / ADC channel 0 |
| Pin 3 | PA1 (ADC1) — Port A bit 1 / ADC channel 1 |
| Pin 4 | PA2 (ADC2) — Port A bit 2 / ADC channel 2 |
| Pin 5 | PA3 (ADC3) — Port A bit 3 / ADC channel 3 |
| Pin 6 | PA4 (ADC4) — Port A bit 4 / ADC channel 4 |
| Pin 7 | PA5 (ADC5) — Port A bit 5 / ADC channel 5 |
| Pin 8 | PA6 (ADC6) — Port A bit 6 / ADC channel 6 |
| Pin 9 | PA7 (ADC7) — Port A bit 7 / ADC channel 7 |
| Pin 10 | PB0 (XCK0/T0) — Port B bit 0 / USART0 clock / Timer0 clock input |
| Pin 11 | PB1 (T1) — Port B bit 1 / Timer1 clock input |
| Pin 12 | PB2 (AIN0/INT2) — Port B bit 2 / analog comparator input 0 / external interrupt 2 |
| Pin 13 | PB3 (AIN1/OC0) — Port B bit 3 / comparator input 1 / Timer0 output compare |
| Pin 14 | PB4 (SS) — Port B bit 4 / SPI slave select |
| Pin 15 | PB5 (MOSI) — Port B bit 5 / SPI master output |
| Pin 16 | PB6 (MISO) — Port B bit 6 / SPI master input |
| Pin 17 | PB7 (SCK) — Port B bit 7 / SPI clock |
| Pin 18 | AREF — ADC analog reference |
| Pin 19 | GND — Ground |
| Pin 20 | AVCC — ADC supply voltage |
| Pin 21 | PC0 (SCL) — Port C bit 0 / Two-Wire clock |
| Pin 22 | PC1 (SDA) — Port C bit 1 / Two-Wire data |
| Pin 23 | PC2 (TCK) — Port C bit 2 / JTAG test clock |
| Pin 24 | PC3 (TMS) — Port C bit 3 / JTAG test mode select |
| Pin 25 | PC4 (TDO) — Port C bit 4 / JTAG test data output |
| Pin 26 | PC5 (TDI) — Port C bit 5 / JTAG test data input |
| Pin 27 | PC6 (TOSC1) — Port C bit 6 / RTC oscillator input |
| Pin 28 | PC7 (TOSC2) — Port C bit 7 / RTC oscillator output |
| Pin 29 | PD0 (RXD0) — Port D bit 0 / USART0 receive |
| Pin 30 | PD1 (TXD0) — Port D bit 1 / USART0 transmit |
| Pin 31 | PD2 (RXD1/INT0) — Port D bit 2 / USART1 receive / external interrupt 0 |
| Pin 32 | PD3 (TXD1/INT1) — Port D bit 3 / USART1 transmit / external interrupt 1 |
| Pin 33 | PD4 (ICP1) — Port D bit 4 / Timer1 input capture |
| Pin 34 | PD5 (OC1A) — Port D bit 5 / Timer1 output compare A |
| Pin 35 | PD6 (OC1B) — Port D bit 6 / Timer1 output compare B |
| Pin 36 | PD7 (OC2) — Port D bit 7 / Timer2 output compare |
| Pin 37 | RESET — Reset input (active low) |
| Pin 38 | XTAL2 — Main oscillator output |
| Pin 39 | XTAL1 — Main oscillator input |
| Pin 40 | NC — Not connected (per datasheet) |
| Pin 41 | NC — Not connected (per datasheet) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
| Pin EP | GND (Exposed Pad) — Ground return / thermal pad, solder to PCB ground |
Typical Applications
ATMEGA164PA-MNR is suitable for 6 applications: Industrial Sensor Nodes, Battery-Powered Metering, HVAC and Appliance Control, Consumer Electronics and Remote Controls, Hobby, Education, and Rapid Prototyping, Building Automation and Access Control.
Industrial Sensor Nodes
The ATMEGA164PA-MNR fits industrial sensor nodes because its 8-channel 10-bit ADC digitizes multiple analog sensors directly, its Two-Wire and SPI interfaces link digital sensors, and two USARTs support RS-485-based field buses through external transceivers. The AVR single-cycle execution delivers deterministic scan loops at 20 MHz while picoPower sleep modes keep average current in the microamp range between readings. Typical topology places the MCU between sensor front ends and a USART-driven RS-485 transceiver, with the ADC sampling at modest rates where the 10-bit resolution suffices. Unlike analog-front-end-heavy designs, integrating the ADC on-chip removes a separate converter from the BOM, cutting cost and board area in compact DIN-rail or node enclosures.
Recommended
Battery-Powered Metering
For electricity, water, and thermal meters, the ATMEGA164PA-MNR's picoPower architecture is the decisive fit: sleep currents drop to sub-uA levels while the real-time counter with its separate oscillator keeps timekeeping alive at minimal current draw. The 512 B EEPROM stores calibration constants and tamper flags through power cycles, and the 10-bit ADC plus internal bandgap reference handles basic load-signal measurement. A typical design wakes the MCU on a pulse or RTC interrupt, performs a measurement burst, updates the LCD or accumulation registers, and returns to deep sleep - the 1 MIPS-per-MHz throughput means the wake window is milliseconds long, preserving battery budget over 10+ year service intervals. The 5V operating capability also simplifies direct interfacing with metering front ends.
Recommended
HVAC and Appliance Control
Home appliances and HVAC controllers benefit from the ATMEGA164PA-MNR's three timers with PWM outputs, which directly drive TRIAC/IGBT gate stages or brushless motor drivers for fans, dampers, and pumps. The 32 GPIO lines cover relays, buttons, and indicators in one chip, while the 8-channel 10-bit ADC reads NTC temperature sensors, pot-position feedback, and supply-voltage supervision. Two USARTs allow one channel for a user-display front board and another for a service/debug port. Because appliance control boards typically run at 5V with noisy relay environments, the AVR's robust 5V I/O structure and classic flash-based firmware model (updated via ISP in production) make manufacturing straightforward without external programming controllers.
Recommended
Consumer Electronics and Remote Controls
Cost-sensitive consumer devices use the ATMEGA164PA-MNR where a single 8-bit MCU replaces scattered logic: it scans keypads through 32 GPIO, drives segment or dot-matrix LCDs through SPI/Two-Wire to display drivers, and manages IR communication via timer-based carrier generation and the ADC-based battery monitor. The 20 MHz clock provides ample headroom for IR protocol decoding in software, and the 16 KB flash accommodates multi-language menu strings and lookup tables. The VQFN (7x7 mm) exposed-pad package keeps the PCB footprint small for handheld form factors while the thermal pad grounds the chip for EMC robustness. The AEC-adjacent green packaging and tape-and-reel supply support high-volume SMT assembly lines.
Recommended
Hobby, Education, and Rapid Prototyping
The ATmega164PA family is a mainstay of the hobbyist and educational ecosystem because it is programmable with free AVR GCC toolchains, MPLAB X, and countless ISP programmers, and its datasheet documents every register exhaustively. The 44-pin VQFN gives students and makers access to all 32 I/O lines in a hand-solderable-with-practice footprint (or use the TQFP44 ATMEGA164PA-AUR variant for breadboard adapters). The 8-channel 10-bit ADC, hardware PWM, and hardware USARTs let newcomers graduate from Blink to motor control and serial projects without external peripherals. Because firmware is portable upward across the pin-compatible 324/644/1284 family, a prototype sketched on the 164PA scales directly to a commercial build when memory runs out.
Recommended
Building Automation and Access Control
Door controllers, occupancy sensors, and room modules in building automation leverage the ATMEGA164PA-MNR's Two-Wire interface to address I2C expanders, RTCs, and EEPROMs on a shared bus, while one USART handles RS-485 multidrop networking and the second services diagnostics. The 16 KB flash holds protocol stacks for simple fieldbus framing plus local logic, and the EEPROM retains IDs, credentials, and counters across power loss. PicoPower sleep keeps wall-mounted, battery-backed modules within energy budgets, and the ADC supervises battery voltage and reads hall-effect or magnetic sensors. The industrial 5V I/O tolerates the electrically noisy environments typical of buildings, reducing external protection component count.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA164PA-MNR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA164P-20MUR | ATMEGA164A-MU | ATMEGA1284P-MUR |
|---|---|---|---|---|
| Package | 44-VQFN (7x7) | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB | 16 KB | 16 KB | 128 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 16 KB |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| picoPower Technology | Yes | Yes (P revision) | No (A revision) | Yes (P revision) |
| Silicon Revision | PA (functionally identical drop-in for P per AVR527) | P (predecessor) | A (cost-optimized) | 1284P family |
| Drop-in Relation | Reference | Pin-to-pin, code-compatible | Pin-to-pin, code-compatible | Pin-to-pin, code-compatible (more memory) |
Key Differentiators
- picoPower low-sleep-current silicon (vs ATMEGA164A-MU)
- Drop-in migration from ATmega164P (vs ATMEGA164P-20MUR)
- Flash upgrade path on identical footprint (vs ATMEGA1284P-MUR)
Design Notes
The 44-VQFN (7x7 mm) exposed pad is the primary ground return and must be soldered to a grounded copper pour with an array of thermal vias (typically 4-9 vias under the pad). Poor exposed-pad soldering causes intermittent ground faults and elevated EMC emissions that are very hard to debug. Follow the Microchip QFN land-pattern application guidance: use a solder-mask-defined aperture slightly smaller than the pad and a printed or stencil paste pattern of ~50-70% coverage on the center pad to prevent float during reflow.
Decouple VCC and AVCC separately: place 100 nF ceramic capacitors within 2-3 mm of pins 1 (VCC) and 20 (AVCC), plus a bulk 4.7-10 uF capacitor near the IC. Connect AVCC to VCC through a low-pass filter (e.g., 10 uH inductor or ferrite plus capacitor) when ADC accuracy matters, and tie AREF to a 100 nF capacitor - never to a large reservoir cap alone. In picoPower designs, ensure residual board leakage and pull-ups on unused I/O are minimized, otherwise sleep current targets will not be met.
Clock speed is voltage-dependent: do not run 20 MHz below the datasheet's minimum VCC for that frequency, or marginal timing will appear only over temperature - check the speed versus VCC curve in the family datasheet before fixing the crystal. RESET (pin 37) needs a 10 k pull-up for reliable power-on; when using debugWire, note that disabling RESET for debugWire output makes subsequent ISP reprogramming require a 12V high-voltage programmer unless debugWire is disabled first. Finally, keep JTAG-enable fuse state in mind: PC2-PC5 default to JTAG and lose general I/O function until the JTAG fuse is cleared.
Compliance Information
Mouser lists the part as GRN (green); Microchip standard ATmega packaging is RoHS-compliant and lead-free. REACH and conflict minerals status not stated in provided data.
