P-Star 45K50 Mini SV

Overview

The Pololu P-Star 45K50 Mini SV is a general-purpose programmable module based on Microchip’s PIC18F45K50 microcontroller, which has 32 KB of flash program memory, 2 KB of RAM, and built-in USB functionality. On-board features of the P-Star (abbreviated P*) include a 16 MHz crystal, a USB Micro-B connector, and three user-controllable indicator LEDs. A switching step-down voltage regulator and power selection circuit allow the board to be powered from either USB or an external 5 V to 36 V source, while a current limit on the USB VBUS supply and reverse protection on VIN help protect it from accidental damage. The board ships with a USB bootloader that makes it easy to program the PIC microcontroller without using an external programmer.

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

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

Features

• Dimensions: 2″ × 0.7″ (2.05″ × 0.7″ including USB Micro-B connector)
• Programmable Microchip PIC18F45K50 microcontroller
  • 32 KB flash (8 KB used by bootloader, leaving 24 KB available for user program by default)
  • 2 KB SRAM
  • 256 bytes of EEPROM
  • Native full-speed USB (12 Mbps)
• Internally clocked at 48 MHz, resulting in execution speeds up to 12 million instructions per second (MIPS)
• Precision 16 MHz crystal
• 30 I/O lines in a small package
  • 28 user I/O pins on the two long sides of the board
  • 2 additional I/O pins available in other locations
  • 25 pins can be configured as analogue inputs
  • 2 PWM output signals (one of which can be sent to four different pins)
  • 5-bit digital-to-analogue converter (DAC) output
• Three user-controllable LEDs
• Reset button
• USB Micro-B connector
• Can be powered from USB or external source regulated to 5 V by onboard regulator
• Operating voltage: 5 V to 36 V
• 5 V logic voltage
• Auxiliary 3.3 V linear regulator
• Reverse-voltage protection on external power input
• Ships with a proprietary USB bootloader developed by Pololu for the P-Star
• Bootloader is usable from Windows, Linux, and Mac OS X with open source software
• No external programmer required
• Compatible with standard Microchip compilers, development tools, and programmers
• Comprehensive user’s guide

Pinout

This diagram identifies the I/O and power pins on the P-Star 45K50 Mini SV. The diagram is also available as a printable PDF (547k pdf). For more information about the PIC18F45K50 microcontroller and its peripherals, see Microchip’s PIC18F45K50 documentation.

Included hardware

Two 1×18-pin breakaway 0.1″ male headers and one 1×7-pin breakaway 0.1″ male header are included with the P-Star 45K50 Mini. These header pins can be soldered in to use the board with perfboards, breadboards, or 0.1″ female connectors.

The P-Star family

The P-Star 45K50 Mini is part of our P-Star family. The table below lists the members of the family and shows the key differences between them.

	P-Star 25K50 Micro	P-Star 45K50 Mini SV
Microcontroller:	PIC18F25K50	PIC18F45K50
User I/O lines:	19	30
Analogue inputs:	14	25
Reset button:
Operating voltage:	5.5 V to 15 V	5 V to 36 V
Regulator type:	linear	switching step-down
Regulated current:(1)	100 mA	500 mA
Auxiliary 3.3 V regulator:
Dimensions:	1″ × 0.6″	2.0″ × 0.7″
Weight:(2)	1.3 g	3.5 g

1 These values are rough approximations for comparison purposes. Available current depends on input voltage, current consumed by the board, ambient conditions, and regulator topology.

2 Without included optional headers.

Dimensions

General specifications

Identifying markings

Notes:

1

Without included optional headers. This measurement includes the USB Micro-B connector, which extends 0.05″ past the edge of the PCB.

2

Without included optional headers.

3

8 KB of the MCU's 32 KB of flash memory is used by the pre-installed USB bootloader. All 32 KB is available if you use an external programmer and erase the bootloader.

4

All 30 can be used as digital I/O, 25 can be used as analogue inputs, and one can be an analogue output. 28 of the 30 are available along the sides for use in a breadboard.

5

For light loads. The regulator's dropout voltage increases approximately linearly with the load, from a few millivolts at no load up to around 0.6 V at 500 mA.

6

On BAT+.