ATmega16/32 Datasheet, Pinout, Minimal Circuit, Maximum Frequency Calculator

The ATmega16 and ATmega32 are similar devices, with the only difference being the available memory. They are the "workhorses" of the AVR line, or have been for quite a while, but they are gradually being outpaced by newer devices, like the ATmegaxx4 family, which is pin-compatible, but functionally advanced. There is still plenty of life left in these devices, but since the ATmega16/32 are limited to 16MHz at 5V, and the ATmega16L/32L are limited to 8MHz at any voltage, there are fewer uses than there used to be.

The ATmega16 and ATmega32 are 40-pin devices with either 16kB or 32kB of flash. They are not the only devices having their particular pinout - the ATmega164/324/644/1284 family shares it. Maximum clock speeds of 16MHz (8MHz for the -L parts) limit their performance. The I/O is the same on both parts, as shown in the parameter table below. The internal oscillator is an 8MHz RC oscillator with three different frequencies - 1MHz, 2MHz, 4MHz, and 8MHz.

Power Supply vs. Maximum Frequency

ATmega16/32's are specified at one of two maximum clock frequencies. With power supplies 4V and under, or for the -L parts at any voltage, the maximum clock frequency is 8MHz. For the standard parts, with a power supply of 4.5V to 5.5V, the clock frequency may be up to 16MHz.

ATmega16/32 Features
Flash 16k32k
EEPROM 0.5k1k
RAM 1k2k
I/O Pins 32
Interrupts 21
ADC Channels 8
RT Counter (w/osc)1
Timers (8-bit) 2
Timers (16-bit) 1
PWM (8-bit) 2
PWM (16-bit) 2
Price (1's) $4.86$3.77
Power Consumption (approximate) 1.25mA/MHz
Maximum I/O Current (per pin) 40mA
Maximum I/O Current (all ports) 100mA
Maximum I/O Current (total) 200mA (PDIP)
Maximum I/O Current (total)400mA (QFP/MLF)

ATmega16/32 Datasheet

Link to ATmega16(L) datasheet from Atmel's website.
Link to ATmega32(L) datasheet from Atmel's website.

ATmega16/32 Pinout

ATmega32-PU pinout ATmega32-AU pinout

ATmega16/32 "Minimal" Circuit Diagram

The circuit below shows a programming port, reset circuit, and a crystal oscillator. Any or all of these could be left off and the device would function perfectly well. By default the unit runs from the 1MHz internal RC oscillator.

ATmega16/32 minimal schematic diagram