ATMEGA16-16MI - AVR 8-bit MCU 16MHz 16KB Flash VQFN-44 | Microchip
MPN: ATMEGA16-16MI β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.1 | $6.10 |
| 10 | $5.55 | $55.50 |
| 100 | $4.92 | $492.00 |
| 500 | $4.48 | $2,240.00 |
| 1,000 | $3.98 | $3,980.00 |
ATMEGA16-16MI Overview
An 8-bit AVR microcontroller is a Harvard-architecture processor that executes most of its 131 powerful instructions in a single clock cycle, sitting in the power management and embedded control hierarchy between tiny 8-pin MCUs and 32-bit ARM devices. AVR MCUs combine program Flash, SRAM, EEPROM, and peripherals such as UART, SPI, I2C (TWI), timers, and ADC on a single die, eliminating external glue logic in embedded systems.
Key features of the ATMEGA16-16MI include an 8-channel 10-bit A/D converter for direct analog sensor interfacing, a JTAG interface for on-chip debugging and boundary scan, two 8-bit and one 16-bit timers with PWM outputs, and serial interfaces covering I2C, SPI, and UART/USART. Self-programming Flash enables field firmware updates over the serial bootloader.
Architecturally, the AVR advanced RISC core uses 32 general-purpose working registers directly connected to the ALU, allowing one-cycle execution and code efficiency approaching C-compiler-friendly density. Separate program and data buses allow simultaneous Flash access and SRAM operation, sustaining the 16 MIPS at 16 MHz rating with 5V supply.
Typical applications include industrial control and sensor nodes, motor-adjacent monitoring circuits using the 10-bit ADC, embedded instrumentation with JTAG debugging, and legacy AVR designs requiring long-term drop-in compatibility within the ATmega family.
Design consideration: the ATMEGA16-16MI operates from 4.5V to 5.5V for full 16MHz speed; place 100nF decoupling capacitors at both VCC pin pairs and route AVCC cleanly for best ADC accuracy.
This page synthesizes distributor pricing context, same-footprint alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA16-16MI β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA16-16MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA16A-MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA32-16MU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA16-16MI Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Maximum Clock Frequency | 16 MHz |
| Program Memory Size | 16 KB (8K x 16) Flash |
| SRAM Size | 1 KB |
| EEPROM Size | 512 B |
| Supply Voltage | 4.5 V to 5.5 V |
| ADC Resolution | 10-bit, 8 channels |
| Timers/Counters | 2 x 8-bit, 1 x 16-bit |
| Communication Interfaces | I2C, SPI, UART/USART |
| JTAG Interface | Yes (on-chip debug, boundary scan) |
| Package | 44-VQFN (MLF, 7x7 mm) |
| Operating Temperature | -40C to +85C |
| Throughput | Up to 16 MIPS at 16 MHz |
| Instruction Set | 131 instructions, mostly single-cycle |
| General Purpose Registers | 32 x 8-bit |
| In-System Programmable Flash | Yes |
| Mounting Type | Surface Mount |
ATMEGA16-16MI Pin Configuration
| Pin 1 | PB5 (SCK) β Port B bit 5 / SPI serial clock |
| Pin 2 | PB6 (MISO) β Port B bit 6 / SPI master-in slave-out |
| Pin 3 | PB7 (MOSI/OC2) β Port B bit 7 / SPI master-out slave-in / Timer2 output compare |
| Pin 4 | RESET β Active-low reset input |
| Pin 5 | VCC β Digital supply voltage |
| Pin 6 | GND β Ground |
| Pin 7 | XTAL2 β Oscillator output |
| Pin 8 | XTAL1 β Oscillator input / external clock |
| Pin 9 | PD0 (RXD) β Port D bit 0 / USART receive |
| Pin 10 | PD1 (TXD) β Port D bit 1 / USART transmit |
| Pin 11 | PD2 (INT0) β Port D bit 2 / external interrupt 0 |
| Pin 12 | PD3 (INT1) β Port D bit 3 / external interrupt 1 |
| Pin 13 | PD4 (OC1B) β Port D bit 4 / Timer1 output compare B |
| Pin 14 | PD5 (OC1A) β Port D bit 5 / Timer1 output compare A |
| Pin 15 | PD6 (ICP1) β Port D bit 6 / Timer1 input capture |
| Pin 16 | PD7 (OC2) β Port D bit 7 / Timer2 output compare |
| Pin 17 | VCC β Digital supply voltage |
| Pin 18 | GND β Ground |
| Pin 19 | PC0 (SCL) β Port C bit 0 / TWI serial clock |
| Pin 20 | PC1 (SDA) β Port C bit 1 / TWI serial data |
| Pin 21 | PC2 (TCK) β Port C bit 2 / JTAG test clock |
| Pin 22 | PC3 (TMS) β Port C bit 3 / JTAG test mode select |
| Pin 23 | PC4 (TDO) β Port C bit 4 / JTAG test data out |
| Pin 24 | PC5 (TDI) β Port C bit 5 / JTAG test data in |
| Pin 25 | PC6 (TOSC1) β Port C bit 6 / Timer2 oscillator input |
| Pin 26 | PC7 (TOSC2) β Port C bit 7 / Timer2 oscillator output |
| Pin 27 | AREF β ADC analog reference |
| Pin 28 | AVCC β ADC supply voltage |
| Pin 29 | PB0 (XCK/T0) β Port B bit 0 / USART clock / Timer0 clock in |
| Pin 30 | PB1 (T1) β Port B bit 1 / Timer1 clock in |
| Pin 31 | PB2 (AIN0/INT2) β Port B bit 2 / analog comparator input / external interrupt 2 |
| Pin 32 | PB3 (AIN1/OC0) β Port B bit 3 / analog comparator input / Timer0 output compare |
| Pin 33 | PB4 (SS) β Port B bit 4 / SPI slave select |
| Pin 34 | ADC6 β ADC input channel 6 (44-pin package only) |
| Pin 35 | ADC7 β ADC input channel 7 (44-pin package only) |
| Pin 36 | PA7 (ADC7) β Port A bit 7 / ADC input 7 |
| Pin 37 | PA6 (ADC6) β Port A bit 6 / ADC input 6 |
| Pin 38 | PA5 (ADC5) β Port A bit 5 / ADC input 5 |
| Pin 39 | PA4 (ADC4) β Port A bit 4 / ADC input 4 |
| Pin 40 | PA3 (ADC3) β Port A bit 3 / ADC input 3 |
| Pin 41 | PA2 (ADC2) β Port A bit 2 / ADC input 2 |
| Pin 42 | PA1 (ADC1) β Port A bit 1 / ADC input 1 |
| Pin 43 | PA0 (ADC0) β Port A bit 0 / ADC input 0 |
| Pin 44 | GND β Ground |
Typical Applications
ATMEGA16-16MI is suitable for 6 applications: Industrial Control and Sensor Nodes, Embedded Instrumentation with JTAG Debug, Motor-Adjacent Monitoring and PWM Control, Legacy AVR System Maintenance, Consumer Appliance and Home Automation Controllers, Security and Access Control Terminals.
Industrial Control and Sensor Nodes
The ATMEGA16-16MI fits industrial control nodes because its -40C to +85C grade, 8-channel 10-bit ADC, and 5V noise-tolerant I/O match typical factory-floor signal conditions. The ADC digitizes 0-5V sensor signals such as potentiometers, NTC thermistors, and 4-20mA-receiver outputs directly, while the 16MHz core executes control loops with 16 MIPS of headroom. Used as a distributed node on an RS-485 bus via the UART, it samples up to 8 channels, stores calibration constants in the 512B EEPROM, and reports over Modbus-RTU. Placing 100nF caps on both VCC pairs and filtering AVCC preserves the 10-bit ADC's 2-LSB accuracy in electrically noisy cabinets.
Recommended
Embedded Instrumentation with JTAG Debug
The ATMEGA16-16MI is well suited to measurement instruments because its JTAG interface provides full on-chip debugging (breakpoints, single-step, register watch) and IEEE-style boundary scan for board-level test - a capability many small AVRs lack. In a bench instrument such as a programmable load or data logger, the 10-bit ADC acquires analog front-end outputs, the 16-bit Timer/Counter1 measures frequency or generates precise PWM, and the EEPROM holds calibration factors written during production. The 16KB Flash accommodates a bootloader plus application firmware, enabling field updates over the UART. Debugging via JTAG shortens bring-up time significantly compared to LED-and-print debugging on devices without it.
Recommended
Motor-Adjacent Monitoring and PWM Control
For motor systems that need supervisory logic rather than high-power control, the ATMEGA16-16MI offers three timers: two 8-bit timers and one 16-bit timer with output-compare channels (OC1A/OC1B), generating up to four PWM outputs for fan, pump, or small DC motor drivers. The 10-bit ADC reads current-sense amplifiers and back-EMF or tachometer inputs on up to 8 channels, letting firmware implement closed-loop speed regulation. The -40C to +85C industrial grade tolerates enclosure heat, and the UART links the node to a supervisory PLC. PWM frequency set around 20kHz keeps operation audible-noise-free; the input-capture pin (ICP1) measures external hall pulses with 62.5ns resolution at 16MHz.
Recommended
Legacy AVR System Maintenance
Many installed products were designed around the ATmega16 in the 1998-2010 era, and the ATMEGA16-16MI serves the exact replacement and continuity market for those boards. Because Microchip (post-Atmel acquisition) still manufactures the family, spare boards for legacy equipment - lab devices, HVAC controllers, point-of-sale hardware - can be serviced with genuine silicon rather than reclaimed parts. The VQFN-44 footprint matches the original PCB land pattern, and fuse-bit settings documented in old project files apply unchanged. Using the JTAG port, service technicians can even read firmware from a working donor unit to clone replacement boards when source code is lost.
Recommended
Consumer Appliance and Home Automation Controllers
In 5V-powered appliances - coffee machines, thermostats, small HVAC units - the ATMEGA16-16MI provides a cost-effective, one-chip controller: 16KB Flash holds the application and bootloader, the 10-bit ADC reads temperature sensors and user potentiometers, and Port C drives seven-segment or LCD segments directly. TWI (I2C) connects to RTC chips and EEPROM expansion, while the UART supports home-automation bridges. Industrial temperature rating adds margin for hot enclosures near heating elements. A single 16MHz crystal and two decoupling capacitors complete the minimal design; watchdog timer and brown-out detector fuses provide the reliability level expected of always-on household products.
Recommended
Security and Access Control Terminals
The ATMEGA16-16MI suits keypad and access-control terminals: Port B and D provide the 4x4 keypad matrix lines plus UART for RS-485 networking, the EEPROM stores access codes and event logs, and the 16-bit timer timestamps entries. The JTAG interface supports production test and secure firmware verification. In a typical door controller, the MCU scans a keypad, drives a relay and status LEDs, and communicates with a central panel at 9600 baud; the -40C rating covers unheated outdoor gate enclosures. 16 MIPS is ample for keypad debouncing, Wiegand-format decoding, and encrypted-token checking, while watchdog supervision restores operation after mains glitches.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA16-16MI β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA16-16MU | ATMEGA16A-MU | ATMEGA32-16MU |
|---|---|---|---|---|
| Package | 44-VQFN (MLF, 7x7 mm) | 44-VQFN (MLF, 7x7 mm) - same | 44-VQFN (MLF, 7x7 mm) - same | 44-VQFN (MLF, 7x7 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 16 KB | 16 KB | 16 KB | 32 KB |
| SRAM | 1 KB | 1 KB | 1 KB | 2 KB |
| Max Clock | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Operating Temperature | -40C to +85C | 0C to +70C | -40C to +85C | 0C to +70C |
| ADC | 8-ch 10-bit | 8-ch 10-bit | 8-ch 10-bit | 8-ch 10-bit |
| JTAG Debug | Yes | Yes | Yes | Yes |
Key Differentiators
- Industrial temperature rating (vs ATMEGA16-16MU)
- Refreshed die with consolidated errata (vs ATMEGA16A-MU)
- Memory upgrade without PCB change (vs ATMEGA32-16MU)
Design Notes
The ATMEGA16-16MI needs 4.5V-5.5V for the 16MHz speed grade. Decouple both VCC pins (5 and 17) with 100nF ceramics placed within 5mm of each pin, plus 4.7-10uF bulk at the board level. Power AVCC (pin 28) from the cleanest 5V available through a 10R/100nF low-pass filter to keep ADC noise low; tie AREF (pin 27) to a 100nF cap or an external reference - never drive it directly while the internal reference is selected.
Fuse configuration is the most common bring-up failure: default clock fuse settings select the internal 1MHz RC oscillator, so an external 16MHz crystal requires reprogramming CKOPT and the CKSEL fuses before the part will run at full speed. Also, JTAG is enabled by default on PC2-PC7, blocking use of those pins as GPIO - disable the JTAGEN fuse in GPIO-heavy designs. Enabling the brown-out detector (BOD at 2.7V/4.0V) is strongly recommended for 5V 16MHz operation.
The VQFN-44 (7x7 mm) MLF package has a center thermal pad that must be soldered to a grounded copper blob on the PCB - this pad is the primary ground connection and also improves EMI. Use an array of small vias (5-6) under the pad to stitch to the ground plane. Keep the crystal within 10mm of XTAL1/XTAL2 with a ground guard ring, and route the analog Port A traces away from the XTAL and UART lines to protect ADC accuracy.
Compliance Information
RoHS/lead-free status per Microchip standard green packaging for current production; REACH and halogen-free declarations should be confirmed on Microchip's product compliance page for the specific date code.
