ATMEGA164PA-MN - 16KB Flash 20MHz AVR MCU | Microchip
MPN: ATMEGA164PA-MN ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.62 | $3.62 |
| 10 | $3.28 | $32.80 |
| 100 | $2.71 | $271.00 |
| 500 | $2.44 | $1,220.00 |
| 1,000 | $2.15 | $2,150.00 |
ATMEGA164PA-MN Overview
An 8-bit AVR microcontroller is a Harvard-architecture RISC device in the broader microcontroller (MCU) hierarchy that integrates flash program memory, SRAM data memory, EEPROM, peripherals and a CPU core on one chip. The AVR ATmega family executes most instructions in a single clock cycle, giving roughly 1 MIPS per MHz of throughput, which places it among the most cycle-efficient 8-bit cores for embedded control, sensing and consumer hardware.
Key features include 32 general purpose I/O lines, 32 general purpose working registers, a real-time counter, three flexible timer/counters with compare modes and PWM outputs, and picoPower low-power technology for battery-operated designs. The device supports 2.7V to 5.5V operation across the VQFN-44, making it usable directly on 3.3V and 5V rails without level shifting in many designs.
Connectivity is rich for an 8-bit MCU: two USARTs, a byte-oriented two-wire serial interface (TWI, I2C-compatible) and an SPI serial port. An 8-channel 10-bit ADC provides analog acquisition for sensor front ends, while the read-while-write flash supports in-system self-programming for firmware updates and data logging.
Typical applications include industrial sensor nodes and control panels, battery-powered metering and IoT endpoints, and consumer appliances requiring dual serial ports for, for example, a display and a radio module simultaneously.
Design consideration: at 20 MHz and 5V the device draws its maximum dynamic current, so for battery designs prefer the internal 8 MHz RC oscillator plus picoPower sleep modes to cut active and standby current dramatically.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for ATMEGA164PA-MN — 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-MN (same form factor and footprint) — differing in ADC, Package, Flash Memory, RoHS Status, Working Registers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA164PA-MNR
✅ Drop-In✓ In Stock
$2.66 / Unit
View Datasheet →ATMEGA164A-MU
✅ Drop-In✓ In Stock
$3.01 / Unit
View Datasheet →ATMEGA164P-20MUR
✅ Drop-In✓ In Stock
$1.5 / Unit
View Datasheet →ATMEGA164P-20MQ
✅ Drop-In✓ In Stock
$2.96 / Unit
View Datasheet →ATMEGA1284P-MUR
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →ATMEGA1284-AUR
✅ Drop-In✓ In Stock
$4.61 / Unit
View Datasheet →ATMEGA164PA-MN Maximum Ratings & Electrical Characteristics
| Core | AVR 8-bit RISC |
| Core Size | 8-bit |
| Speed | 20 MHz |
| Flash Memory | 16 KB (8K x 16) ISP, read-while-write |
| EEPROM | 512 B |
| SRAM | 1 KB |
| GPIO | 32 |
| Working Registers | 32 general purpose |
| Timers/Counters | 3 (with compare modes and PWM) |
| USART | 2 |
| TWI (I2C) | Yes, byte-oriented two-wire serial interface |
| SPI | Yes |
| ADC | 8-channel, 10-bit |
| Low Power Technology | picoPower |
| Real-Time Counter | Yes |
| Package | 44-VQFN (7x7 mm) with exposed pad |
| Mounting Type | Surface Mount |
| RoHS Status | Green (per Mouser listing) |
ATMEGA164PA-MN Pin Configuration
| Pin 1 | PB5 — Port B, bit 5 (PCINT13/MOSI) |
| Pin 2 | PB6 — Port B, bit 6 (PCINT14/XTAL1/TOSC1) - oscillator input |
| Pin 3 | PB7 — Port B, bit 7 (PCINT15/XTAL2/TOSC2) - oscillator output |
| Pin 4 | VCC — Digital supply voltage |
| Pin 5 | GND — Ground |
| Pin 6 | VCC — Digital supply voltage |
| Pin 7 | GND — Ground |
| Pin 8 | PA0 — Port A, bit 0 (ADC0 / PCINT0) |
| Pin 9 | PA1 — Port A, bit 1 (ADC1 / PCINT1) |
| Pin 10 | PA2 — Port A, bit 2 (ADC2 / PCINT2) |
| Pin 11 | PA3 — Port A, bit 3 (ADC3 / PCINT3) |
| Pin 12 | PA4 — Port A, bit 4 (ADC4 / PCINT4) |
| Pin 13 | PA5 — Port A, bit 5 (ADC5 / PCINT5) |
| Pin 14 | PA6 — Port A, bit 6 (ADC6 / PCINT6) |
| Pin 15 | PA7 — Port A, bit 7 (ADC7 / PCINT7) |
| Pin 16 | AREF — Analog reference voltage for ADC |
| Pin 17 | GND — Analog ground (AGND) |
| Pin 18 | AVCC — Analog supply voltage for ADC (connect to VCC via filter) |
| Pin 19 | PC0 — Port C, bit 0 (SCL/PCINT16) - TWI clock |
| Pin 20 | PC1 — Port C, bit 1 (SDA/PCINT17) - TWI data |
| Pin 21 | PC2 — Port C, bit 2 (TCK/PCINT18) |
| Pin 22 | PC3 — Port C, bit 3 (TMS/PCINT19) |
| Pin 23 | PC4 — Port C, bit 4 (TDO/PCINT20) |
| Pin 24 | PC5 — Port C, bit 5 (TDI/PCINT21) |
| Pin 25 | PC6 — Port C, bit 6 (TOSC1/PCINT22) |
| Pin 26 | PC7 — Port C, bit 7 (TOSC2/PCINT23) |
| Pin 27 | PD0 — Port D, bit 0 (RXD0/PCINT24) - USART0 receive |
| Pin 28 | PD1 — Port D, bit 1 (TXD0/PCINT25) - USART0 transmit |
| Pin 29 | PD2 — Port D, bit 2 (RXD1/INT0/PCINT26) |
| Pin 30 | PD3 — Port D, bit 3 (TXD1/INT1/PCINT27) |
| Pin 31 | PD4 — Port D, bit 4 (XCK1/OC1B/PCINT28) |
| Pin 32 | PD5 — Port D, bit 5 (XCK0/OC1A/PCINT29) |
| Pin 33 | PD6 — Port D, bit 6 (OC2B/ICP0/PCINT30) |
| Pin 34 | PD7 — Port D, bit 7 (OC0A/OC1C/PCINT31) |
| Pin 35 | VCC — Digital supply voltage |
| Pin 36 | GND — Ground |
| Pin 37 | RESET — Reset input (active low); held low for ISP entry |
| Pin 38 | VCC — Digital supply voltage |
| Pin 39 | GND — Ground |
| Pin 40 | PB0 — Port B, bit 0 (XCK0/T0/PCINT8) |
| Pin 41 | PB1 — Port B, bit 1 (T1/CLKO/PCINT9) |
| Pin 42 | PB2 — Port B, bit 2 (AIN0/INT2/PCINT10) |
| Pin 43 | PB3 — Port B, bit 3 (AIN1/OC0B/PCINT11) |
| Pin 44 | PB4 — Port B, bit 4 (SS/PCINT12) - SPI slave select |
Typical Applications
ATMEGA164PA-MN is suitable for 6 applications: Industrial Sensor Nodes and Control Panels, Battery-Powered Metering and IoT Endpoints, Consumer Appliance Control Boards, Dual-UART Communication Gateways, Motor Control and PWM Actuation, Analog Data Acquisition Front Ends.
Industrial Sensor Nodes and Control Panels
The ATMEGA164PA-MN fits industrial sensor nodes because its 8-channel 10-bit ADC digitizes up to eight analog transducers while the 32 GPIO lines drive relays, indicators and local keypads. picoPower sleep modes keep standby current low between sampling intervals, and the 44-pad VQFN-44 exposed-pad package withstands vibration better than leaded alternatives. In control panel use, the device typically runs from an internal RC oscillator with watchdog supervision, polling sensors over the ADC and TWI bus, then reporting via one USART to a Modbus or custom RS-485 link. The second USART remains available for local HMI or service diagnostics, which is a common reason designers pick this part over single-UART ATmega328-class MCUs.
Recommended
Battery-Powered Metering and IoT Endpoints
For battery-powered metering and IoT endpoint designs, the ATMEGA164PA-MN's picoPower technology is the primary selection driver: power-down and power-save modes clocked by the real-time counter allow the MCU to sleep at microamp-level current and wake periodically to sample the 8-channel 10-bit ADC or a TWI sensor. The 16 KB flash accommodates metering firmware plus a lightweight communication stack over one USART (e.g., RF module), while the second USART services a service/debug port. The 512 B EEPROM stores calibration constants that survive battery replacement. Because the VQFN-44 operates from low supply voltages typical of lithium cells with a regulator, designers can achieve multi-year battery life without compromising I/O count.
Recommended
Consumer Appliance Control Boards
The ATMEGA164PA-MN suits consumer appliance control boards needing dual serial links: one USART commonly drives a segment/LCD display module while the second handles an external RF remote receiver or bootloader service interface. The three timer/counters with compare modes generate PWM for motor speed control, heater triac phase control or buzzer tones, and the 32 GPIO lines cover keypad matrices, LEDs and limit switches without port expanders. The green RoHS VQFN-44 supports standard reflow assembly. Its read-while-write flash enables field firmware updates via bootloader over UART, a valued feature for post-deployment feature additions in appliance fleets. The 20 MHz core executes button scanning, PID loops and communication concurrently at comfortable margin.
Recommended
Dual-UART Communication Gateways
Designs bridging two serial domains - for example RS-232 service port to RS-485 field bus, or UART radio to UART host - benefit directly from the ATMEGA164PA-MN's two independent USARTs, a feature absent from single-UART 8-bit MCUs at this price point. The 16 KB flash holds buffering plus two protocol stacks, the 1 KB SRAM provides packet buffers, and hardware flow flexibility supports baud rates up to the MCU's 20 MHz clock limits. The TWI interface can additionally attach an I2C EEPROM or RTC for message logging. The picoPower core keeps average draw low in duty-cycled gateway deployments, and the exposed-pad VQFN-44 grounds provide low-impedance return paths for the transceivers.
Recommended
Motor Control and PWM Actuation
The ATMEGA164PA-MN's three timer/counters with compare modes deliver multiple PWM channels for DC motor speed control, servo actuation or LED dimming, while the 20 MHz core executes closed-loop control (PI/PID) using feedback from the 10-bit ADC. Timer input-capture features measure tachometer pulses for speed feedback, and interrupt-driven UART handles command traffic simultaneously. Typical usage: one 8-bit timer generates a fast carrier PWM, a 16-bit timer handles precise timing or capture, and the ADC samples current-shunt and potentiometer inputs. The 44-pin VQFN provides enough GPIO for H-bridge enable/direction signaling plus protection interlocks, avoiding the need for external logic in compact actuator boards.
Recommended
Analog Data Acquisition Front Ends
The 8-channel 10-bit ADC makes the ATMEGA164PA-MN a compact data acquisition front end for temperature (NTC/PT100 with conditioning), voltage, current and potentiometer inputs. Differential ADC modes with programmable gain suit bridge sensors such as load cells and pressure elements, while the internal bandgap reference and AREF pin support ratiometric measurement techniques that cancel supply drift. Firmware can oversample and decimate in the 1 KB SRAM for effective resolution beyond 10 bits, then stream results over USART or store them in the 512 B EEPROM. picoPower modes allow duty-cycled acquisition - wake, sample a burst, transmit, sleep - which is the standard pattern for wireless sensor logging nodes.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA164PA-MN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA164PA-MNR | ATMEGA164A-MU | ATMEGA164P-20MUR | ATMEGA1284P-MUR |
|---|---|---|---|---|---|
| Package | VQFN-44 (7x7) EP | VQFN-44 (7x7) - same | VQFN-44 (MLF) - same pad pattern | VQFN-44 (7x7) - same | VQFN-44 (7x7) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 16 KB | 16 KB | 16 KB | 16 KB | 128 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 1 KB | 16 KB |
| EEPROM | 512 B | 512 B | 512 B | 512 B | 4 KB |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| USART Count | 2 | 2 | 2 | 2 | 2 |
| ADC | 8-ch 10-bit | 8-ch 10-bit | 8-ch 10-bit | 8-ch 10-bit | 8-ch 10-bit |
| Low Power Revision | picoPower (PA) | picoPower (PA) - identical | ATmega164A generation | picoPower (P) predecessor | picoPower (P) |
Key Differentiators
- picoPower low-power optimization (vs ATMEGA164A-MU)
- Identical die availability on reel (vs ATMEGA164PA-MNR)
- Cost vs memory headroom trade-off (vs ATMEGA1284P-MUR)
Design Notes
The VQFN-44 has a large exposed ground pad on the underside; connect it to a solid ground plane with an array of thermal vias (e.g., 4x4 grid of ~0.3 mm vias) to ensure reliable grounding and heat spreading - solder voids here are the most common assembly defect for the -MN package. Use a fine-pitch stencil (~100 um, 50-60% coverage) and no-clean flux for the 0.5 mm-class pad geometry. Verify pad dimensions against the Microchip datasheet package drawing before layout release, as the MLF and VQFN land patterns differ slightly in aperture size.
Decouple each VCC pin pair (pins 4/6, 35/38) with 100 nF ceramic capacitors placed within 2-3 mm of the pins, and AVCC (pin 18) with 100 nF plus an RC filter (e.g., 10 ohm in series) from VCC to keep ADC noise low. Connect AREF to a clean reference; enable the internal bandgap or use an external precision reference for ratiometric-critical measurements. Ground AGND (pin 17) at a single quiet point to avoid digital return currents corrupting ADC readings. Keep the crystal loop (PB6/PB7) compact with 22 pF-class load caps per the crystal datasheet.
RESET (pin 37) must remain low while entering ISP programming - ensure no driver holds this pin during production programming, and consider a 10 kohm pull-up plus ESD protection for field reliability. If you migrate between ATmega164PA and ATmega1284P in the same footprint, remember the larger part has 4 KB EEPROM and different interrupt vector counts; recompile with the correct device selected rather than reusing binary images. Also confirm fuse settings (JTAGEN, clock source) after programming, since factory defaults run the internal 1 MHz RC oscillator, not the 20 MHz crystal.
Compliance Information
Mouser listing describes the part as 'Grn' (green / RoHS-compliant, lead-free). REACH, halogen-free and conflict-minerals status not stated in the provided data - verify via Microchip's product page certificates.
