# ATmega16A chip: specs and pinout > 8-bit AVR microcontroller with 16 KB in-system programmable flash, 1 KB SRAM and 512 bytes EEPROM, 32 I/O lines. Bare chip; the listing does not say… [HTML version](https://soldr.ai/docs/boards/atmega16a) [Docs](https://soldr.ai/docs) / [Boards](https://soldr.ai/docs/boards) 8-bit AVR microcontroller with 16 KB in-system programmable flash, 1 KB SRAM and 512 bytes EEPROM, 32 I/O lines. Bare chip; the listing does not say which package. Every value cites its sourceOfficial pinout [Buy on Compoden](https://compoden.com/products/atmega-16a-microcontroller) ## Specs | Spec | Value | Source | |---|---|---| | Operating voltage | 2.7 V to 5.5 V | source Features, Operating Voltages | | Speed grade | 0 to 16 MHz | source Features, Speed Grades | | Operating temperature | -40 C to 85 C | source Electrical characteristics, DC Characteristics conditions (TA = -40C to 85C) | | Flash / SRAM / EEPROM | 16 KB / 1 KB / 512 bytes | source Features, High Endurance Non-volatile Memory segments | | Programmable I/O lines | 32 | source Features, I/O and Packages | | Packages | 40-pin PDIP, 44-lead TQFP, 44-pad QFN/MLF | source Features, I/O and Packages | | ADC | 8-channel 10-bit; 8 single-ended; 7 differential channels in TQFP package only | source Features, Peripheral Features | | PWM channels | 4 | source Features, Peripheral Features | | Active current | 0.6 mA at 1 MHz, 3 V, 25 C | source Features, Power Consumption | | Power-down current | < 1 uA at 3 V, 25 C | source Features, Power Consumption | ## Power | | Value | Source | |---|---|---| | Supply | 2.7 V to 5.5 V | source Features, Operating Voltages and Power Consumption | | Current | 0.6 mA active at 1 MHz, 3 V, 25 C; < 1 uA power-down | source Features, Operating Voltages and Power Consumption | ## Pinout Bare chip, no module board. The pin table is the 40-pin PDIP figure from the chip data sheet; the TQFP/QFN pin numbers are different. The listing does not state the package, so check the chip in hand against the figure. | Pin | Function | Voltage | Notes | Source | |---|---|---|---|---| | 1 | PB0 (XCK/T0) | | | source Section 1 Figure 1-1, PDIP | | 2 | PB1 (T1) | | | source Section 1 Figure 1-1, PDIP | | 3 | PB2 (INT2/AIN0) | | | source Section 1 Figure 1-1, PDIP | | 4 | PB3 (OC0/AIN1) | | | source Section 1 Figure 1-1, PDIP | | 5 | PB4 (SS) | | | source Section 1 Figure 1-1, PDIP | | 6 | PB5 (MOSI) | | | source Section 1 Figure 1-1, PDIP | | 7 | PB6 (MISO) | | | source Section 1 Figure 1-1, PDIP | | 8 | PB7 (SCK) | | | source Section 1 Figure 1-1, PDIP | | 9 | RESET | | | source Section 1 Figure 1-1, PDIP | | 10 | VCC | | | source Section 1 Figure 1-1, PDIP | | 11 | GND | | | source Section 1 Figure 1-1, PDIP | | 12 | XTAL2 | | | source Section 1 Figure 1-1, PDIP | | 13 | XTAL1 | | | source Section 1 Figure 1-1, PDIP | | 14 | PD0 (RXD) | | | source Section 1 Figure 1-1, PDIP | | 15 | PD1 (TXD) | | | source Section 1 Figure 1-1, PDIP | | 16 | PD2 (INT0) | | | source Section 1 Figure 1-1, PDIP | | 17 | PD3 (INT1) | | | source Section 1 Figure 1-1, PDIP | | 18 | PD4 (OC1B) | | | source Section 1 Figure 1-1, PDIP | | 19 | PD5 (OC1A) | | | source Section 1 Figure 1-1, PDIP | | 20 | PD6 (ICP1) | | | source Section 1 Figure 1-1, PDIP | | 21 | PD7 (OC2) | | | source Section 1 Figure 1-1, PDIP | | 22 | PC0 (SCL) | | | source Section 1 Figure 1-1, PDIP | | 23 | PC1 (SDA) | | | source Section 1 Figure 1-1, PDIP | | 24 | PC2 (TCK) | | JTAG pin; the sheet lists a JTAG interface on port C | source Section 1 Figure 1-1, PDIP | | 25 | PC3 (TMS) | | JTAG pin; the sheet lists a JTAG interface on port C | source Section 1 Figure 1-1, PDIP | | 26 | PC4 (TDO) | | JTAG pin; the sheet lists a JTAG interface on port C | source Section 1 Figure 1-1, PDIP | | 27 | PC5 (TDI) | | JTAG pin; the sheet lists a JTAG interface on port C | source Section 1 Figure 1-1, PDIP | | 28 | PC6 (TOSC1) | | | source Section 1 Figure 1-1, PDIP | | 29 | PC7 (TOSC2) | | | source Section 1 Figure 1-1, PDIP | | 30 | AVCC | | | source Section 1 Figure 1-1, PDIP | | 31 | GND | | | source Section 1 Figure 1-1, PDIP | | 32 | AREF | | | source Section 1 Figure 1-1, PDIP | | 33 | PA7 (ADC7) | | | source Section 1 Figure 1-1, PDIP | | 34 | PA6 (ADC6) | | | source Section 1 Figure 1-1, PDIP | | 35 | PA5 (ADC5) | | | source Section 1 Figure 1-1, PDIP | | 36 | PA4 (ADC4) | | | source Section 1 Figure 1-1, PDIP | | 37 | PA3 (ADC3) | | | source Section 1 Figure 1-1, PDIP | | 38 | PA2 (ADC2) | | | source Section 1 Figure 1-1, PDIP | | 39 | PA1 (ADC1) | | | source Section 1 Figure 1-1, PDIP | | 40 | PA0 (ADC0) | | | source Section 1 Figure 1-1, PDIP | ## Build with it Project ideas for the ATmega16A chip. Each link opens Soldr with the prompt filled in; Soldr assigns the pins, checks power and shows how to wire every part. - [A custom circuit board around an ATmega 16A that shows the temperature from a DS18B20 module on a TM1637 4-digit display](https://app.soldr.ai/?prompt=I%20want%20to%20build%20a%20custom%20circuit%20board%20around%20an%20ATmega%2016A%20that%20shows%20the%20temperature%20from%20a%20DS18B20%20module%20on%20a%20TM1637%204-digit%20display): Digital I/O on ports B and D drives both modules; a 5 V supply sits inside the 2.7-5.5 V range. Programmed over its SPI pins. - [Light-following servo demo](https://app.soldr.ai/?prompt=I%20want%20to%20build%20a%20custom%20circuit%20board%20around%20an%20ATmega%2016A%20that%20turns%20a%20micro%20servo%20toward%20the%20brighter%20of%20two%20light%20sensor%20modules): Two ADC inputs on port A read the light modules and PD4/PD5 (OC1B/OC1A) give a hardware PWM output for the servo. Power the servo from its own 5 V supply and join the grounds. A learning project. - [Serial-controlled relay board](https://app.soldr.ai/?prompt=I%20want%20to%20build%20a%20custom%20circuit%20board%20around%20an%20ATmega%2016A%20that%20switches%20a%20relay%20module%20and%20an%20LED%20when%20it%20receives%20a%20character%20from%20a%20computer%20through%20a%20USB%20serial%20adapter): PD0 (RXD) and PD1 (TXD) are the chip's USART pins. Keep the relay on low-voltage loads such as an LED. - [Reaction-time game](https://app.soldr.ai/?prompt=I%20want%20to%20build%20a%20custom%20circuit%20board%20around%20an%20ATmega%2016A%20that%20runs%20a%20reaction-time%20game%20with%20a%20push%20button%2C%20a%20buzzer%20and%20a%20TM1637%20display): Simple digital I/O and a timer are all it needs; the chip has two 8-bit timers and one 16-bit timer. ## Common mistakes - AVCC outside the allowed window: AVCC must stay within 2.7 to 5.5 V and within VCC - 0.3 V to VCC + 0.3 V (source: [link](https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-8154-8-bit-AVR-ATmega16A_Datasheet.pdf), SPI serial programming figure note) - Wiring the wrong package: the chip ships as 40-pin PDIP, 44-lead TQFP or 44-pad QFN/MLF, and the pin numbers differ (source: [link](https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-8154-8-bit-AVR-ATmega16A_Datasheet.pdf), Features and Section 1 Figure 1-1) - Treating port C pins PC2 to PC5 as free I/O: the JTAG interface (TCK, TMS, TDO, TDI) shares them (source: [link](https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-8154-8-bit-AVR-ATmega16A_Datasheet.pdf), Features: JTAG interface; pinout Figure 1-1) ## Not covered by the official source - Package on the listing is not stated; the 40-pin PDIP table is given and the TQFP/QFN table in the same sheet differs. - Speed grade voltage pairing is not stated separately in the Features list (listed as 0 to 16 MHz). - Typical current at 16 MHz is not given on this page. ## Sources - [link](https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-8154-8-bit-AVR-ATmega16A_Datasheet.pdf) (Atmel-8154C ATmega16A datasheet, 07/2014)