8 bit AVR Microcontroller ATMEGA32U4-AU
21 September 2023
Ⅱ. Symbol and Footprint of ATMEGA32U4-AU
Ⅵ. What types of products is ATMEGA32U4-AU suitable for?
ATMEGA32U4-AU is an 8-bit MEGAAVR device based on the AVR enhanced RISC architecture. It has USB 2.0 device module and JTAG interface for chip debugging. It uses TQFP-44 package and operates at 16Mhz. This microcontroller has 44 pins, 26 of which are I/O pins for input and output. Its memory type is FLASH, the operating voltage range is 2.7V to 5.5V, and the temperature range is - 40°C to 85°C.
This microcontroller has a rich instruction set and 32 general-purpose working registers. Among them, these 32 registers are directly connected to the arithmetic logic unit (ALU), allowing two independent register single instructions to be executed in a single clock cycle. This design makes code execution more efficient and enables throughput up to ten times faster than traditional CISC microcontrollers.
This device provides 16/32K bytes of in-system programmable flash memory, 512Bytes/1K bytes of EEPROM, and 1.25/2.5K bytes of SRAM. It also features 26 general-purpose I/O lines, 32 general-purpose working registers, four flexible timer/counter modes and PWM. In addition, this device is equipped with a high-speed timer/counter, a USART, a byte-oriented 2-wire serial interface, a 12-channel 10-bit ADC, an on-chip calibrated temperature sensor, and a programmable watchdog timers, an SPI serial port, and IEEE standards.
Replacement and equivalent：
• ATMEGA32U2
1. It is equipped with an on-chip 2-cycle multiplier so it can perform multiplication calculations faster.
2. This controller adopts an advanced RISC architecture and has 135 powerful instructions, most of which can be executed in a single cycle. Its general-purpose working registers and completely static operation characteristics enable it to have higher operating speed and efficiency.
3. It also has ADC noise reduction function. It is capable of stopping the CPU and other I/O modules while minimizing switching noise during ADC transitions.
4. It is equipped with 16KB/32KB in-system self-programming, 1.25KB/2.5KB internal SRAM, and 512Bytes/1KB internal EEPROM. These memories retain data even after the power is turned off.
5. By executing powerful instructions in a single clock cycle, it can achieve throughput close to 1MIPS while achieving an ideal balance between power consumption and speed.
6. It also has multiple power-saving modes such as idle mode and power-down mode, which can effectively reduce power consumption while ensuring that the system of normal operation.
1. AREF
This is the analog reference pin (input) for the A/D Converter.
2. UVCC
USB Pads Internal Regulator Input supply voltage.
3. VCC
Digital supply voltage.
4. AVCC
AVCC is the supply voltage pin (input) for all the A/D Converter channels. If the ADC is not used, it should be externally connected to VCC. If the ADC is used, it should be connected to VCC through a low-pass filter.
5. D-
USB Full speed / Low Speed Negative Data Upstream Port. Should be connected to the USB D- connector pin with a serial 22Ωresistor.
6. D+
USB Full speed / Low Speed Positive Data Upstream Port. Should be connected to the USB D+ connector pin with a serial 22Ωresistor.
7. UCAP
USB Pads Internal Regulator Output supply voltage. Should be connected to an external capacitor (1µF).
8. VBUS
USB VBUS monitor input.
9. RESET
Reset input. A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running. The minimum pulse length is given in Table 8-2 on page 53. Shorter pulses are not guaranteed to generate a reset.
10. XTAL1
Input to the inverting Oscillator amplifier and input to the internal clock operating circuit.
11. XTAL2
Output from the inverting Oscillator amplifier.
12. GND
Ground.
13. UGND
USB Pads Ground.
14. Port B (PB7..PB0)
Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port B output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up resistors are activated. The Port B pins are tristated when a reset condition becomes active, even if the clock is not running. Port B has better driving capabilities than the other ports.
15. Port C (PC7,PC6)
Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port C output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up resistors are activated. The Port C pins are tristated when a reset condition becomes active, even if the clock is not running. Only bits 6 and 7 are present on the product pinout.
16. Port D (PD7..PD0)
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port D output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tristated when a reset condition becomes active, even if the clock is not running.
17. Port E (PE6,PE2)
Port E is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port E output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port E pins that are externally pulled low will source current if the pull-up resistors are activated. The Port E pins are tristated when a reset condition becomes active, even if the clock is not running. Only bits 2 and 6 are present on the product pinout.
18. Port F (PF7..PF4, PF1,PF0)
Port F serves as analog inputs to the A/D Converter. Port F also serves as an 8-bit bi-directional I/O port, if the A/D Converter channels are not used. Port pins can provide internal pull-up resistors (selected for each bit). The Port F output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port F pins that are externally pulled low will source current if the pull-up resistors are activated. The Port F pins are tri-stated when a reset condition becomes active, even if the clock is not running. Bits 2 and 3 are not present on the product pinout. Port F also serves the functions of the JTAG interface. If the JTAG interface is enabled, the pull-up resistors on pins PF7(TDI), PF5(TMS), and PF4(TCK) will be activated even if a reset occurs.
• Keyboard and mouse: Since ATMEGA32U4-AU supports USB communication, it is often used to design peripherals such as keyboard and mouse.
• Consumer electronics: digital photo frames, audio players, smart remote controls, etc.
• Automation systems: ATMEGA32U4-AU can be used in various automation systems such as home automation, industrial automation, and agricultural automation to control and monitor equipment and sensors.
• Electronic toys: remote controls, small robots, game controllers, etc.
• Handheld devices: digital multimeters, remote controls, small instruments, etc.
• Embedded systems: ATMEGA32U4-AU is suitable for embedded systems that need to control and monitor various external devices and sensors. It has enough I/O pins to connect and control various external hardware.
Frequently Asked Questions
1. What is the key feature of the ATMEGA32U4-AU that sets it apart from other AVR microcontrollers?
The primary distinguishing feature of the ATMEGA32U4-AU is its built-in USB controller, which allows it to communicate with USB devices directly without the need for external components.
2. What is the IC equivalent of ATMEGA32U4-AU ?
The equivalent of ATMEGA32U4-AU is ATMEGA32U2, ATMEGA16U4, ATMEGA32U4-AUR, ATMEGA32U4-MU and AT90USB1286.
3. What is the clock speed of the ATMEGA32U4-AU?
The ATMEGA32U4-AU can be operated at various clock speeds, typically up to 16 MHz, but it can be overclocked to higher frequencies under certain conditions.
4. What is the purpose of the USB interface on the ATMEGA32U4-AU?
The USB interface allows the microcontroller to connect to USB devices, such as computers, to exchange data, emulate USB peripherals, or even act as a USB host in some applications.
