The circuits on this page are switch machine drivers that can be used to operate Stall-Motor type switch machine motors. The circuits use LM324 Quad or 358 Dual operational Amplifier chips to provide a PUSH-PULL output to reverse the polarity of the supply to the switch machine motors.
The drivers use direct control inputs such as switches or CMOS and TTL logic devices.
The advantage of this type of driver is low cost and, in the case of the 324, two drivers per package can be built. These operational amplifiers can only supply enough output current to drive one switch machine per driver.
Note: Testing on this type of circuit showed that OpAmps were too unstable to allow the control input to float as would be the case with push button switches. This instability can be over come with added resistors and capacitors but the increased cost makes the 556 Timer based switch machine driver a better choice for push button controls.
The explanations for the circuits on these pages cannot hope to cover every situation on every layout. For this reason be prepared to do some experimenting to get the results you want. This is especially true of circuits such as the "Across Track Infrared Detection" circuits and any other circuit that relies on other than direct electronic inputs, such as switches.
If you use any of these circuit ideas, ask your parts supplier for a copy of the manufacturers data sheets for any components that you have not used before. These sheets contain a wealth of data and circuit design information that no electronic or print article could approach and will save time and perhaps damage to the components themselves. These data sheets can often be found on the web site of the device manufacturers.
Although the circuits are functional the pages are not meant to be full descriptions of each circuit but rather as guides for adapting them for use by others. If you have any questions or comments please send them to the email address on the Circuit Index page.
23 January, 2012