The 74LS244 buffer protects Port 2 of the 8051 microcontroller from the motor circuit and provides sufficient current to drive the output transistor. The dc motor is connected to a +5-V dc supply ...

The transistors’ feature a 4.4-mm × 4.0-mm footprint and can dissipate up to 2.1 W. In quantities of 10,000, the ZX5T851Z and ZX5T951Z are priced at $0.24 each.