Ordering Information: Minimum order is $10 (not including shipping costs); maximum order is $100.
Orders below $10 or above $100 will be automatically refunded.
International shipping is available. Shipments to the United States, Canada, or Mexico are trackable and insured.
Shipments to all other countries are not trackable, and are also not insured.
L298 Motor Driver PC Board
.jpg) |
.jpg) |
| Bare L298 PC Board | Assembled L298 PC Board |
The L298 Motor Driver PC Board implements a complete motor driver solution for controlling two DC motors.
The board is also capable of implementing the L298's current-sensing feature to detect excessive current-draw.
Temporarily out of stock.
The L298 PC board was originally developed in conjunction with the motor controller experiments presented in PICAXE Microcontroller Projects for the Evil Genius. In order to fully understand how to use the L298 board, you would either need to have access to the Evil Genius book, or read the L298 Motor Driver Datasheet.
The complete schematic and parts list for the L298 PC Board are shown below:
L298 PC Board Schematic |
.jpg) |
L298 PC Board Parts List
(All parts are available at JRHackett.net)
| Label | Description | C1 | Capacitor, Electrolytic, 470uF |
| C2 | Capacitor, Ceramic, .01uF |
| D1-D8 | Diode, Schottky, 1N5818 |
| L298 | L298 Dual Full-Bridge Driver |
| R1,R2 | Resistor, 0.5 ohm, 3 Watt |
| [None] | Header, Male, Straight, 10 Pins |
| [None] | Screw Terminals, 5mm pitch, 6 Pins |
Assembling the L298 Board
The L298 PC board is very easy to assemble. As usual, it's best to proceed from the smallest to the largest parts. The one exception in this case is the 10-pin male header (the shorter side of which is inserted from the bottom of the board and then soldered on the top). It's best to install this header last so that the bottom of the board can be more easily cleaned. (We'll get to that shortly.)
The only other aspect of the board that requires a brief explanation is the row of 12 holes in the area of the screw terminal. (See the photo of the bare board, at the top of this page.) When I designed the first prototype PC board for the L298 board, I included this row of holes so that I had the option of installing a 12-pin header in the place of the 6-pin screw terminal, which enabled me to make quick and easy breadboard connections for testing low-power motors with the prototype board. (Actually, I assembled and tested two prototypes, one with the breadboard header installed and the other with the screw terminal installed.)
I'm sure that most people will want to use the screw terminals for their motor connections, but just in case you prefer to conduct your own breadboard experiments with low power motors, I decided to leave the row of 12 holes on the final PC board so that you can omit the Screw Terminal, and in its place install a 12-pin straight male header (inserted from the bottom of the board) for connection to a second breadboard. If you decide to do so, don't forget that breadboards aren't designed to handle high-power motors. The breadboard can easily discolor (or even melt) as a result of the heat produced by the high currents required by large motors.
When all the parts have been soldered in place [except for the breadboard header(s)], make sure all the excess leads have been clipped from the bottom of the board. At this point you may want to rub the bottom of the board a few times on a piece of emery-type sandpaper to remove any sharp edges. You can use flux remover and a tooth brush to clean the bottom of the board, but I have found that ordinary paint thinner works just as well for this purpose and it's easier on your hands. Once you have cleaned the bottom of the board, you can insert the male header from the bottom of the board, and solder it in place on the top.
Testing the Completed L298 Board
The easiest way to test the completed L298 board is to install it in a simple PICAXE breadboard circuit and write a program to exercise the various functions of the L298 IC. One possible testing scenario is presented in detail in the Evil Genius book, but you could also use the test setup shown below to develop your own testing procedure. In the photo, I'm using two tiny stripboard circuits, each of which contains a red and a green LED connected in opposing polarities so that I can simulate a motor running forward or in reverse. Motor speed can also be easily checked this way: high speed = bright LED, and low speed = dim LED. Lastly, note the 9-Volt battery that I'm using as my "motor" supply voltage. For the L298 IC, the motor supply voltage must be at least 2.5V higher than the logic supply (+5V), so it's not possible to use the +5V breadboard supply to power the LEDs in this test setup.
.jpg)
If you have any problems getting your L298 board to function properly, email me at Ron@JRHackett.net and I will do what I can to help.