SparkFun – Resettable Fuse PTC
SparkFun: COM-08357
Description: This is a handy little device that can save your system from smoking. A resettable fuse (also known as a PTC) is a resistor that has very unique properties.
For this model, if your circuit tries to draw more than 250mA of current (if you have a bad short for instance) the PTC would ‘trip’ (by heating up). The increased resistance (trip state) would break the circuit and allow only a small leakage current.
The leakage current may still be enough to hurt some electronics but it’s much less than the 3A that the short may have allowed. Removing the short, the PTC ‘resets’ and allows current up to 250mA to flow again. It’s a resettable fuse that protects your system! Good for use on battery powered devices that need to protect again high-current accidental discharges.
The thermal pictures to the right do a great job of showing what happens when the PTC is tripped. The first thermal picture shows a voltage regulating circuit in its normal state. In the second picture the circuit is shorted, notice how hot the PTC gets (213 °F!) as it limits the amount of damaging current going through the circuit. Major thanks to Joshua Weaver for the great thermal shots!
Don Luc
Steren – Phenolic plate 4.5 x 4.5 cm for projects
Steren: 155
Description: Bakelite phenolic copper plate of 4.5 x 4.5 cm, engraved and perforated with holes 164 and 4 components to fix the plate. Ideal for projects or prototypes.
Don Luc
SparkFun – Arduino Stackable Header Kit
SparkFun: PRT-10007
Description: These headers are made to work with the Arduino Main Board, Arduino Pro, and the Arduino Mega. They are the perfect height for clearing the USB-B connector and great for stacking multiple shields. This kit includes 4 headers (2 8-pin and 2 6-pin), enough to connect a shield to an Arduino Main Board. These are the same headers we use in our tutorials and with our own shields.
Don Luc
SparkFun – JST Jumper 2 Wire Assembly
SparkFun: PRT-09914
Description: This is a simple two wire cable. Great for jumping from board to board or just about anything else. There is a 2-pin JST connector on one end, bare cable on the opposite end. It also comes with the mating connector for the JST.
Dimensions: 6″ length
Don Luc
SparkFun – ProtoShield for Arduino Pro Mini
SparkFun: DEV-09709
Description: This is a small prototyping shield for the Arduino Pro Mini. If your project requires just a little bit more space for your external circuitry, this might be a perfect addition. 38 unconnected PTHs are provided for your prototyping needs.
The shield fits the small form factor of the Arduino Pro Mini – connecting to the ‘top’ four pins on each side of the Mini (‘GND’-‘TXO’ & ‘VCC’-‘RAW’). There are small buses for VCC, GND and RAW. In addition to the power buses, the serial pins are also broken out on the shield. The analog and digital pins are not broken out on the shield.
Features:
- VCC, RAW and GND buses
- Serial (RXI & TXO) pins broken out to small buses
- Works with both 5V and 3.3V Pro Mini versions
- Upholds the Pro Mini’s small form factor
- 38 unconnected PTHs for prototyping
Don Luc
SparkFun – Alcohol Gas Sensor – MQ-3 – Gas Sensor Breakout Board
SparkFun: SEN-08880
Description: This alcohol sensor is suitable for detecting alcohol concentration on your breath, just like your common breathalyzer. It has a high sensitivity and fast response time. Sensor provides an analog resistive output based on alcohol concentration. The drive circuit is very simple, all it needs is one resistor. A simple interface could be a 0-3.3V ADC.
Features:
- 5V DC or AC circuit
- Requires heater voltage
- Operation Temperature: -10 to 70 degrees C
- Heater consumption: less than 750mW
Dimensions:
- 16.8mm diameter
- 9.3 mm height without the pins
SparkFun: BOB-08891
Description: Simple breakout board for the MQ – 3, MQ – 4 and MQ – 6 gas sensors. All you need is VCC at 5V, GND, and a resistor to an ADC, that is it.
Note: This is the PCB only. Sensors listed below.
Dimensions: 16.8mm diameter
Don Luc
Steren – Phenolic board 10.7 x 14 cm, for projects
Steren: 150CC
Description: Phenolic copper plate 10.7 x 14 cm (1/4 carte), engraved and perforated. Ideal for projects or prototypes.
Don Luc
SparkFun – Break Away Headers – Straight
SparkFun: PRT-00116
Description: A row of headers – break to fit. 40 pins that can be cut to any size. Used with custom PCBs or general custom headers.
Features:
- Pin Style: Square
- Number of Pins: 40
- Pin Spacing: 0.1″ (2.54 mm)
- Pin Length: 11.5 mm
Don Luc
SparkFun – ProtoBoard – Square 2″
SparkFun: PRT-08811
Description: This is a very simple but handy, 2″ square, double sided perf board. Standard 0.1″ spacing with a 4-40 (3mm) holes for mounting. Great for quickly prototyping stackable circuits.
Don Luc
Pololu – Universal Aluminum Mounting Hub for 3mm Shaft, #4-40 Holes (2-Pack)
Pololu: 1078
These universal aluminum mounting hubs allow you to mount custom wheels and mechanisms to 3 mm diameter motor shafts. The set includes two hubs, two #4-40 set screws for securing the hubs to motor shafts, and one 0.05? Allen wrench for use with the set screws. Each hub has four threaded mounting holes for #4-40 screws (not included).
We have an assortment of universal mounting hubs available, spanning several shaft sizes and featuring mounting holes threaded for metric or imperial screws: 3mm – #4-40
Description
These universal mounting hubs are designed to work with most 3 mm diameter shafts, including round shafts, “D” shafts, and Tamiya’s 3 mm hexagonal shafts. Each of the two included hubs has four mounting holes for #4-40 screws (not included), letting you mount custom wheels or mechanisms to your motors. The two included #4-40 hex set screws (one for each hub) allow secure coupling of shaft to hub, and a 0.05? hex wrench (often the smallest size in SAE Allen wrench sets) is included for use with the set screws. A dimension diagram of the hub is available under the resources tab.
The picture to the right shows a hub with one of Pololu’s mini metal gearmotors and a Pololu mini metal gearmotor bracket. These hubs will work with any Pololu mini/15.5D mm metal gearmotor or micro metal gearmotor, and they also work with 60 mm, 70 mm, 80 mm, and 90 mm Pololu wheels.
- Size: 17.5 mm diameter × 5 mm thick
- Weight: 2.8 g
- Shaft diameter: 3 mm
- Mounting hole size: #4-40
Notes:
- For a single hub only (without set screw)
- This is also the size of the set screw
Don Luc