ATMEGA48PA-MMN - 4KB Flash 20MHz AVR MCU QFN-28 | Microchip
MPN: ATMEGA48PA-MMN β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.18 | $1.18 |
| 10 | $1.06 | $10.60 |
| 100 | $0.92 | $92.00 |
| 500 | $0.83 | $415.00 |
| 1,000 | $0.74 | $740.00 |
ATMEGA48PA-MMN Overview
An AVR 8-bit microcontroller is a Harvard-architecture RISC processor that executes most of its 131 instructions in a single clock cycle. Within the power-management hierarchy, an MCU of this class integrates CPU, program memory, data memory, timers, ADC, and communication peripherals on one die, replacing multi-chip logic designs in cost-sensitive embedded systems. The ATmega family spans 4KB to 32KB Flash devices sharing one core and one development toolchain.
Key features include the picoPower technology set (idle, power-down, power-save, and standby sleep modes) for ultra-low average consumption in battery products, three flexible timer/counters with compare modes, a 10-bit ADC, and the 32 general-purpose working registers that give AVR its high code density. The PA suffix denotes the low-power picoPower silicon revision of the ATmega48 generation.
Architecturally, the AVR core pairs the single-cycle ALU with on-chip in-system programmable (ISP) Flash, allowing firmware updates through the SPI-based ICSP interface using tools such as MPLAB SNAP or the Atmel-ICE debugger. The MMN VQFN-28 (4x4 mm) package suits dense two-layer PCBs and offers an exposed die-attach pad for improved grounding and thermal behavior.
Typical applications include battery-powered sensor nodes, small home-automation and IoT end nodes, industrial control subfunctions, and consumer appliance front-ends where 4KB of Flash and 512B of SRAM are sufficient.
Design consideration: at 5V and 20 MHz, confirm your supply falls within the high-voltage operating range listed by distributors, and respect the picoPower clock-configuration constraints when scaling frequency downward for low-power modes.
This page synthesizes distributor listings, drop-in family alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA48PA-MMN 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 ATMEGA48PA-MMN (same form factor and footprint) β differing in EEPROM, Flash Memory, General Purpose I/O, Low Power Technology, Package.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA48PB-MMN
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA88PA-MMN
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$2.05 / Unit
View Datasheet βATMEGA168PA-MMN
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA328P-MMH
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA48-20MMU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA48PA-MMN Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Flash Memory | 4 KB (2K x 16) ISP Flash |
| EEPROM | 256 B |
| SRAM | 512 B |
| Maximum Clock Frequency | 20 MHz |
| Instructions | 131 instructions, most single-cycle |
| General Purpose I/O | 23 I/O lines |
| Working Registers | 32 general purpose registers |
| Timers/Counters | 3 flexible timer/counters with compare modes |
| Supply Voltage (per distributor listing) | 4.5 V to 5.5 V (high-voltage range) |
| Operating Temperature (per Mouser) | up to 105 C |
| Package | 28-VQFN (4x4 mm), 0.45 mm pitch, 1 mm height, exposed pad |
| Mounting Type | Surface Mount |
| Programming Interface | ICSP (SPI), In-Circuit Debug via 2 I/O pins + reset |
| Low Power Technology | picoPower sleep modes (idle, power-down, power-save, standby) |
| Lifecycle Status | ACTIVE (per DigChip) |
ATMEGA48PA-MMN Pin Configuration
| Pin 1 | PD3 (PCINT19/OC2B/INT1) β Port D bit 3, pin-change interrupt 19, Timer2 output compare B, external interrupt 1 |
| Pin 2 | PD4 (PCINT20/XCK/T0) β Port D bit 4, pin-change interrupt 20, USART external clock, Timer0 clock input |
| Pin 3 | GND β Ground (per datasheet; see PB migration caution for pin 3) |
| Pin 4 | PD5 (PCINT21/OC0B/T1) β Port D bit 5, pin-change interrupt 21, Timer0 output compare B, Timer1 clock input |
| Pin 5 | PD6 (PCINT22/OC0A/AIN0) β Port D bit 6, pin-change interrupt 22, Timer0 output compare A, analog comparator positive input |
| Pin 6 | VCC β Digital supply voltage (per datasheet; see PB migration caution for pin 6) |
| Pin 7 | PD7 (PCINT23/AIN1) β Port D bit 7, pin-change interrupt 23, analog comparator negative input |
| Pin 8 | PB0 (PCINT0/CLKO/ICP1) β Port B bit 0, pin-change interrupt 0, clock output, Timer1 input capture |
| Pin 9 | PB1 (PCINT1/OC1A) β Port B bit 1, pin-change interrupt 1, Timer1 output compare A |
| Pin 10 | PB2 (PCINT2/SS/OC1B) β Port B bit 2, pin-change interrupt 2, SPI slave select, Timer1 output compare B |
| Pin 11 | PB3 (PCINT3/OC2A/MOSI) β Port B bit 3, pin-change interrupt 3, Timer2 output compare A, SPI master output |
| Pin 12 | PB4 (PCINT4/MISO) β Port B bit 4, pin-change interrupt 4, SPI master input |
| Pin 13 | PB5 (PCINT5/SCK) β Port B bit 5, pin-change interrupt 5, SPI serial clock |
| Pin 14 | AVCC β ADC supply voltage |
| Pin 15 | ADC6 β ADC input channel 6 (analog-only pin) |
| Pin 16 | ADC7 β ADC input channel 7 (analog-only pin) |
| Pin 17 | PB6 (PCINT6/XTAL1/TOSC1) β Port B bit 6, crystal oscillator input 1 / Timer oscillator input |
| Pin 18 | PB7 (PCINT7/XTAL2/TOSC2) β Port B bit 7, crystal oscillator output 2 / Timer oscillator output |
| Pin 19 | PC6 (RESET/PCINT14) β Reset input (active low) / pin-change interrupt 14 |
| Pin 20 | PD0 (PCINT16/RXD) β Port D bit 0, pin-change interrupt 16, USART receive |
| Pin 21 | PD1 (PCINT17/TXD) β Port D bit 1, pin-change interrupt 17, USART transmit |
| Pin 22 | PD2 (PCINT18/INT0) β Port D bit 2, pin-change interrupt 18, external interrupt 0 |
| Pin 23 | PC0 (PCINT8/ADC0) β Port C bit 0, pin-change interrupt 8, ADC channel 0 |
| Pin 24 | PC1 (PCINT9/ADC1) β Port C bit 1, pin-change interrupt 9, ADC channel 1 |
| Pin 25 | PC2 (PCINT10/ADC2) β Port C bit 2, pin-change interrupt 10, ADC channel 2 |
| Pin 26 | PC3 (PCINT11/ADC3) β Port C bit 3, pin-change interrupt 11, ADC channel 3 |
| Pin 27 | PC4 (PCINT12/SDA/ADC4) β Port C bit 4, pin-change interrupt 12, TWI data, ADC channel 4 |
| Pin 28 | PC5 (PCINT13/SCL/ADC5) β Port C bit 5, pin-change interrupt 13, TWI clock, ADC channel 5 |
Typical Applications
ATMEGA48PA-MMN is suitable for 6 applications: Battery-Powered Sensor Nodes, Industrial Control Subfunctions, Home Automation and IoT End Nodes, Consumer Appliance Front-Ends, Analog Measurement Front-Ends, Prototype and Education Platforms.
Battery-Powered Sensor Nodes
The ATMEGA48PA-MMN's picoPower technology is the primary reason it fits battery-powered sensor nodes: idle, power-down, power-save, and standby sleep modes let the MCU sleep between wake events so average current drops to microamp levels, directly extending battery life. With 4KB Flash and 512B SRAM, the device comfortably hosts sensor polling loops, simple protocol stacks, and calibration routines. A typical topology wakes the MCU on a timer or pin-change interrupt, reads a sensor through the ADC or SPI/I2C, transmits a short packet, and returns to power-save. Quantified benefit: duty-cycling at 1% active time reduces average consumption roughly 100x versus always-on operation, enabling multi-year coin-cell life.
Recommended
Industrial Control Subfunctions
In industrial automation, the ATMEGA48PA-MMN handles localized control tasks such as relay sequencing, PWM-driven actuator control, and limit-switch monitoring, offloading the main PLC or gateway. Its three flexible timer/counters with compare modes generate precise PWM without CPU overhead, and the 10-bit ADC digitizes potentiometer, thermistor, or current-shunt feedback. Distributor listings rate the device to 105 C, covering control-cabinet ambient conditions. The 23 I/O lines interface optocouplers, drivers, and indicators directly. Placed as a 5V, 20 MHz controller, the single-cycle RISC core executes interrupt-latency-critical loops deterministically. Trade-off: at 4KB Flash, communication-heavy Modbus implementations are tight, so use the pin-compatible ATMEGA88PA-MMN when protocol stacks grow.
Recommended
Home Automation and IoT End Nodes
Smart-home end nodes such as wall switches, dimmers, and sensor pucks use the ATMEGA48PA-MMN where cost per unit dominates the BOM. The 4KB ISP Flash accommodates RF-module-at-driver logic while the 23 I/O lines handle buttons, triacs, and status LEDs. The exposed-pad 28-VQFN (4x4 mm, 0.45 mm pitch) keeps the controller footprint under 25 mm squared, enabling compact mains-safe enclosures. ICSP programming through two I/O pins plus reset allows firmware updates during manufacturing via an MPLAB SNAP. Performance consideration: run at reduced clock (for example 8 MHz) in always-listening nodes to cut dynamic current; at 5V high-voltage range the device tolerates noisy mains-derived supplies better than 3V-only MCUs.
Recommended
Consumer Appliance Front-Ends
Small appliance and consumer-product front panels - coffee makers, fans, chargers, toys - use the ATMEGA48PA-MMN to scan keypads, drive segment or matrix LED displays, and manage simple state machines. The 32 general-purpose working registers and single-cycle instruction execution keep debouncing and display-refresh routines responsive at modest clock rates, and picoPower sleep modes meet standby-power expectations in off-state. The green plastic 4x4 mm VQFN package satisfies halogen-restricted consumer material requirements per distributor packaging descriptions. Design consideration: the 105 C rating (per Mouser) accommodates enclosure heat soak, but verify the frequency-versus-voltage speed grade when operating at reduced supply in battery products.
Recommended
Analog Measurement Front-Ends
The ATMEGA48PA-MMN's 10-bit ADC, internal bandgap reference options, and differential-input capability make it a compact analog measurement controller for thermistor bridges, potentiometer sensing, and battery-voltage monitors. Running the ADC from a reduced system clock lowers ADC noise for small-signal channels, while the 512B SRAM buffers sample windows for simple averaging or RMS estimation. The VQFN exposed pad grounds the analog die region, reducing ground bounce when ADC and digital I/O share the same die. Quantified workflow: sample at modest rates, oversample 4x-16x for extra effective bits, and use power-down between conversions to preserve battery. For precision beyond 10-bit resolution, add an external ADC and keep the mega48 as the host.
Recommended
Prototype and Education Platforms
Because the ATmega48/88/168/328 family shares one core, one instruction set, and one toolchain (MPLAB X with SNAP or Atmel-ICE), the ATMEGA48PA-MMN is a natural low-cost teaching and prototyping device. Students can develop on the 4KB part and migrate identical code to ATMEGA328P-based boards without relearning architecture. The ICSP header uses only two I/O pins plus reset, teaching minimal in-circuit debugging methodology. On 28-VQFN adapters or the ATMEGA48PA-AU TQFP variant for breadboards, peripheral exercises covering timers, ADC, sleep modes, and interrupts map one-to-one to industrial practice. Benefit: 4KB Flash enforces lean, register-level C or assembly habits early, while the upgrade path removes ceiling pressure later.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA48PA-MMN β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA48PB-MMN | ATMEGA88PA-MMN | ATMEGA168PA-MMN | ATMEGA328P-MMH | ATMEGA48-20MMU |
|---|---|---|---|---|---|---|
| Package | 28-VQFN (4x4 mm) | 28-VQFN (4x4 mm) - same | 28-VQFN (4x4 mm) - same | 28-VQFN (4x4 mm) - same | 28-VQFN (4x4 mm) - same | 28-VQFN (4x4 mm) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology (Atmel) |
| Flash Memory | 4 KB | 4 KB | 8 KB | 16 KB | 32 KB | 4 KB |
| SRAM | 512 B | 512 B | 1 KB | 1 KB | 2 KB | 512 B |
| EEPROM | 256 B | 256 B | 512 B | 512 B | 1 KB | 256 B |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Low-Power Technology | picoPower (PA revision) | picoPower (PB revision) | picoPower (PA revision) | picoPower (PA revision) | picoPower-class (P revision) | Standard (non-picoPower) |
| Drop-In Status | Reference device | Drop-in with pin 3/pin 6 cautions (Microchip migration note) | Pin-to-pin, more flash | Pin-to-pin, more flash | Pin-to-pin, highest flash | Pin-to-pin, non-picoPower silicon |
Key Differentiators
- Lowest-cost point of the pin-compatible ATmega QFN-28 family (vs ATMEGA328P-MMH)
- picoPower silicon revision (vs ATMEGA48-20MMU)
- Clear forward-migration path (vs ATMEGA48PB-MMN)
- Same-footprint memory scaling without PCB change (vs ATMEGA88PA-MMN)
Design Notes
The 28-VQFN (4x4 mm, 0.45 mm pitch) MMN package requires an exposed-pad land pattern. Solder the center pad to a grounded copper area with a 3x3 via array stitching to the ground plane; this provides both the primary GND connection and heat spreading for the die. Use 0.2 mm solder-mask-defined apertures on the 0.45 mm pitch perimeter lands and inspect with X-ray or AOI since QFN joints are hidden. If your assembler cannot rework QFN reliably, prototype with the TQFP-32 ATMEGA48PA-AU instead - the code is identical.
Distributor listings place the 20 MHz high-speed operating point in the 4.5 V to 5.5 V supply range. Decouple VCC and AVCC separately with 100 nF ceramic capacitors placed within 2 mm of each pin, plus a 4.7-10 uF bulk capacitor per rail, and connect AVCC to VCC through an LC filter (ferrite bead plus capacitor) when ADC accuracy matters. Estimated: at 5 V and 20 MHz, active current is on the order of 10 mA class per AVR family behavior, so a 100 mA-class 5 V regulator is adequate for MCU-only designs - verify against the datasheet current table for your exact conditions.
When migrating designs from ATMEGA48PA to the newer ATMEGA48PB, Microchip's online documentation specifies two mandatory checks: pin 3 - if connected to GND, the pin must not be actively driven or ACO must not be enabled; pin 6 - if connected to VCC, the pin must not be actively driven. Also remember PB5-PB7 double as the ISP/SPI and crystal pins: if you use PB6/PB7 for an external crystal, they are unavailable for ICSP clock/data routing on other pins, so place the ICSP header on MOSI/MISO/SCK/RESET and keep RESET pulled up through a 10k resistor with a programming header pin.
To exploit picoPower sleep modes, configure all unused I/O as inputs with internal pull-ups enabled or drive them to defined levels - floating pins in power-down mode cause shoot-through current that can dominate the sleep budget. Estimated: in a duty-cycled sensor node sleeping 99% of the time, average current is approximately I_active x 0.01 + I_sleep x 0.99, so even tens of microamps of leakage on floating pins can double battery consumption. Disable the digital input buffer on ADC-only pins (ADC6/ADC7) and use the watchdog or Timer2 asynchronous tick for wake-up.
Compliance Information
Distributor packaging description mentions GREEN plastic package material, which generally indicates RoHS-oriented material selection, but explicit RoHS/REACH/lead-free declarations were not present in the provided data - verify on the Microchip product page. AEC-Q100 status not stated in provided data.
