SKU: 27685105773

A-Star 32U4 Micro Pololu 3101

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Description

A-Star 32U4 Micro Pololu 3101The A Star 32U4 Micro is a tiny programmable module featuring the ATmega32U4 AVR microcontroller. It packs a Micro USB interface and 18 digital input output pins (of which 7 can be used as PWM outputs and 8 as analog inputs) onto a board measuring only 1 0. 6 and ships preloaded with an Arduino compatible bootloader. A Star 32U4 Micro, bottom view with U. S. quarter for size reference. Overview The Pololu A Star 32U4 Micro is a general purpose

The A-Star 32U4 Micro is a tiny programmable module featuring the ATmega32U4 AVR microcontroller. It packs a Micro-USB interface and 18 digital input/output pins (of which 7 can be used as PWM outputs and 8 as analog inputs) onto a board measuring only 1″ × 0.6″ and ships preloaded with an Arduino-compatible bootloader.


 

A-Star 32U4 Micro, bottom view with U.S. quarter for size reference.

Overview

The Pololu A-Star 32U4 Micro is a general-purpose programmable module based on the ATmega32U4 AVR microcontroller from Microchip (formerly Atmel), which has 32 KB of flash program memory, 2.5 KB of RAM, and built-in USB functionality. Onboard features of the A-Star (abbreviated A*) include a 16 MHz resonator, a USB Micro-B connector, an in-system programming (ISP) header, and a pair of indicator LEDs. A voltage regulator and power selection circuit allow the board to be powered from either USB or an external 5.5 V to 15 V source, while a resettable PTC fuse on the USB VBUS supply and reverse protection on VIN help protect it from accidental damage.

The A-Star 32U4 Micro breaks out 15 general-purpose I/O lines along two rows of pins, including 7 usable as PWM outputs and 8 usable as analog inputs; another three GPIO pins can be accessed through the 6-pin ISP header. It fits all this into a 20-pin dual in-line package (DIP) measuring only 1″ × 0.6″ (even smaller than competing ATmega32U4 boards like the Teensy 2.0 and Pro Micro), and its 0.1″ pin spacing makes the A* easy to use with solderless breadboards, perfboards, and 0.1″-pitch connectors.

Our comprehensive user’s guide provides the basics you need to get started with the A-Star as well as detailed technical information for advanced users.

This product requires a USB A to Micro-B cable (not included) to connect to a computer.

Features

  • Dimensions: 1″ × 0.6″ (1.05″ × 0.6″ including USB Micro-B connector)
  • Programmable 16 MHz ATmega32U4 AVR microcontroller
    • 32 KB flash (4 KB used by bootloader, leaving 28 KB available for user program by default)
    • 2.5 KB SRAM
    • 1 KB EEPROM
    • Native full-speed USB (12 Mbps)
  • Preloaded with Arduino-compatible bootloader (no external programmer required)
  • Many I/O lines in a small package
    • 15 general-purpose I/O pins available along the sides of the board
    • 3 additional I/O pins available on ISP header
    • 7 pins can be configured as hardware PWM outputs
    • 8 pins can be configured as analog inputs
  • 2 user-controllable LEDs
  • Can be powered from USB or external 5.5 V to 15 V source on VIN
  • PTC fuse on VBUS supply
  • Reverse-voltage protection on VIN supply
  • 6-pin ISP header for use with an external programmer
  • Comprehensive user’s guide

Arduino compatibility

The A-Star 32U4 ships with a preloaded Arduino-compatible bootloader (which uses 4 KB of flash memory, leaving 28 KB available for the user program). We provide a software add-on that enables the board to be easily programmed from the Arduino environment.

The A-Star 32U4 uses the same microcontroller as the Arduino Leonardo and Arduino Micro and runs at the same frequency, making it just as powerful. Although the larger boards offer a few more I/O pins, the A-Star 32U4 Micro fits in an area half that of the Arduino Micro, and it takes up only 11% as much area as a standard full-size Arduino!

 

Pololu A-Star 32U4 Micro, Pololu A-Star 32U4 Mini SV, Arduino Micro, and Arduino Leonardo.

Pinout

 

This diagram identifies the I/O and power pins on the A-Star 32U4 Micro; it is also available as a printable PDF (409k pdf). For more information about the ATmega32U4 microcontroller on this board, see Microchip’s ATmega32U4 documentation.

Printed on the A* circuit board are indicators that you can use to quickly identify each pin’s capabilities: a triangle next to the pin means it can be used as an analog input, and a square wave symbol under the pin number means it can be used as a PWM output.

The board can either be powered directly from the USB 5 V supply or from a separate 5.5 V to 15 V source on the VIN pin, which is reduced to 5 V by a 100 mA low-dropout (LDO) regulator; you can access this 5 V supply through the 5V power output pin. Additionally, the ATmega32U4 contains an internal 3.3 V regulator whose output is available on the 3V3 pin. Current drawn from the 3V3 output should not exceed about 50 mA, and when the board is being powered through VIN, the sum of the 5V output current, 3V3 output current, GPIO output current, and current used by the board itself (typically about 25 mA) should not exceed 100 mA.

Included hardware

A 1×20-pin breakaway 0.1″ male header is included with the A-Star 32U4 Micro, which can be soldered in to use the board with perfboards, breadboards, or 0.1″ female connectors. (The headers might ship already separated into two 1×10 pieces.) Also included is a 2×3 header that can be installed to allow external programming of the microcontroller through the AVR ISP interface, such as with our USB AVR programmer.

A-Star 32U4 Micro with included optional headers.

A-Star 32U4 Micro with soldered headers and connected USB cable.

The A-Star family

 

From top to bottom: A-Star 328PB Micro, 32U4 Micro, 32U4 Mini SV, and 32U4 Prime SV.

The A-Star 32U4 Micro is a part of our larger A-Star family, all of whose members are based on AVR microcontrollers and are preloaded with Arduino-compatible bootloaders. The table below shows some key features and specifications of our A-Star microcontroller boards to help you choose the right one for your application.







A-Star 328PB Micro A-Star 32U4 Micro A-Star 32U4 Mini ULV

A-Star 32U4 Mini LV

A-Star 32U4 Mini SV
A-Star 32U4 Prime LV

A-Star 32U4 Prime SV
A-Star 32U4 Robot Controller LV

A-Star 32U4 Robot Controller SV
Microcontroller: ATmega328PB ATmega32U4
User I/O lines: 24 18 26 26(1) 26(1)
PWM outputs: 9 7 7 7 7(1)
Analog inputs: 8 8 12 12 12(1)
Ground access points: 6 2 4 43 44
User LEDs: 1 2 3 3 3
User pushbuttons: 3 3
USB interface: Yes Yes Yes Yes
Reset button: Yes   Yes Yes Yes
Power switch:     Yes Yes
Buzzer option:     Yes Yes
microSD option:     Yes  
LCD option:     Yes  
Motor drivers:       Yes
Operating voltage: 3.3V VCC: 3.8 V to 15 V
5V VCC: 5.5 V to 15 V
5.5 V to 15 V ULV: 0.5 V to 5.5 V
LV: 2.7 V to 11.8 V
SV: 5 V to 40 V
LV: 2 V to 16 V
SV: 5 V to 36 V
LV: 2.7 V to 11 V
SV: 5.5 V to 36 V
Regulator type: 3.3 V or 5 V linear 5 V linear 5 V switching

ULV: step-up
LV: step-up/step-down
SV: step-down
5 V switching

LV: step-up/step-down
SV: step-down
5 V switching

LV: step-up/step-down
SV: step-down
Regulated current:(2) 100 mA 100 mA ULV: 500 mA
LV: 1 A
SV: 800 mA
LV: 1.8 A
SV: 1 A
LV: 1 A
SV: 1.5 A
Dimensions: 1.3″ × 0.7″ 1″ × 0.6″ 1.9″ × 0.7″ 2.8″ × 2.1″ 2.6″ × 2.2″
Weight: 1.5 g(3) 1.3 g(3) 3.4 g(3) 13 g to 33 g 14 g to 23 g
1 Some microcontroller resources are used by on-board hardware.
2 These values are rough approximations for comparison purposes. Available current depends on input voltage, current consumed by the board, ambient conditions, and regulator topology. See product documentation and performance graphs for details.
3 Without included optional headers.

Specifications

Parameter Value
Size 0.6″ × 1.05″ × 0.18″
Weight 1.3 g
Processor ATmega32U4 @ 16 MHz
Ram size 2560 bytes
Program memory size 32 Kbytes
Motor channels 0
User i/o lines 18
Minimum operating voltage 5.5 V
Maximum operating voltage 15 V
Logic voltage 5 V
Reverse voltage protection? Y
External programmer required? N
PCB dev codes ac01a
Other PCB markings 0J8063

Resources

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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
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SKU: 27685105773

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Michael F.
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My 7 month Golden Retriever puppy has way too much energy. And I go to work in the dark, and come home in the dark. This was the solution. First of all if you get this, I suggest a UV flashlight to charge it. Most of these phosphors for glow in the dark items have very strong optical absorption in the UV, and the UV will charge both the ball and the launcher in seconds. I shine the light at the launcher with the ball in it, since you can then see where the launcher is when you are trying to load the ball. I use this UV flashlight, which takes qty=3 AA batteries. https://www.amazon.com/gp/product/B01A5KLUG2/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1 I have never used a launcher before and I learned it within about 10 throws. It is easy to have a basic competence. I live in a suburban area and I send the ball across front lawns, trying to avoid the street, or hitting my neighbors parked cars. I can consistently do this now with the launcher, which is a big improvement over the old tennis racket and ball routine. I got the 25" medium ball launcher, which also works for tennis balls. The scoop goes easily over the Chuck-it balls. My older dog is not taking to it, since he was trained to sit and give the ball. This works better if you have the dog drop the ball so you can scoop it. The glow in the dark ball has 2 holes (think wiffle) that have a low pitch whooshing whistle as you toss it. This is great for my puppy who gets easily distracted as the glowing ball and the noise it makes really helps him propery mark it. Overall I think the dog retrieves better in the dark as there are fewer distractions, and I feel better about the dark for retrieving since there is no traffic early in the morning (both foot and auto). The ball has some squish to it and the pup loves to chew on it as he brings it back. I do not let him play with it when we are not retrieving...better for him to destroy his chew bones and ropes. It took him about 5 tries to get the hang of picking up the new ball. The older dog (13yr old golden) does not like it and only goes for tennis balls. I can tell already this is my puppy's favorite toy ever. I put it up out of reach across coat hooks in the entryway, and that pup will sit there staring at it, then at me, then at it hoping that I will go out and use it. With bounces and rolls and the puppy missing the grab this has gone 100-150' across 3 front lawns. I am looking forward to giving it a go in the park on the weekend. Main problems with the pup now are he likes to parade around me with the ball when he comes back, then lie down and try to give it a proper chew. If I use my launcher to pick it up, I have to put my foot between him and the ball since he will try to get it back fast. Overall this launcher means faster pickup, faster release, more accurate release, good distance, and a better run per time allocation than the old tennis racket and ball routine.
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