MIKROE-233 MikroElektronika

Manual mikroDRIVE All Mikroelektronikas development systems feature a large number of peripheral modules expanding microcontrollers range of application and making the process of program testing easier. In addition to these modules, it is also possible to use numerous additional modules linked to the development system through the I/O port connectors. Some of these additional modules can operate as stand-alone devices without being connected to the microcontroller. MikroElektronika Additional BoardmikroDRIVE mikroDRIVE Additional Board The mikroDrive additional board enables digital outputs capable of providing current of only up to several milliamperes to be connected to devices requiring driving current of up to several hundreds milliamperes (relays, coils, stepper motors, heaters, printer hammers etc.). All this is enabled by the ULN2803 circuit provided on the mikroDrive board. This circuit is composed of 8 Darlington transistors that can power loads up to 260 W in total (8x350 mA, 95V). All these transistors are of open collector type with clamp diodes. The diodes protect them against high voltage of self-induction. The mikroDrive additional board can be used as a stand-alone device or along with some of Mikroelektronikas development systems. This board is connected to the microcontrollers output port via a standard 2x5 connector. Figure 1: mikroDRIVE additional board Figure 2: mikroDRIVE connected to a development system Jumper J1 is used to select power supply source for the ULN2803s output drivers. When this jumper is set to the VCC position, Darlington drivers are powered with 5V (power supply voltage). When this jumper is set to the VCC-EXT position, the drivers outputs are powered with voltage provided via the CN10 connector. This voltage goes up to 50V. Figure 3: mikroDRIVE connection schematic Figure 4: A ULN2803s driver connection schematic MikroElektronika