Driver Click Board™

The Driver Click Board™ retains the connection flexibility of the DRV777 IC, offering a nine-pole spring terminal that can be used to implement and realize a wide range of different applications. Featuring kickback protection diodes, high impedance control inputs, input RC snubber network for improved reliability, pull-down input resistors that allow tri-stating, up to 2kV ESD protection, and more, this Click board™ is a perfect solution for developing various types of motor driving applications, regardless of whether it is a stepper motor, brushed DC motor, brushless motor, or a combination of these. A special feature of the Driver Click Board™ is the possibility to combine integrated drivers in parallel, allowing to sink up to 1A of current.

How Does The Driver Click Board™ Work?

The Driver Click Board™ uses the DRV777, an integrated motor and relay driver from Texas Instruments. This IC has seven integrated current sink drivers. Each channel has a free-wheeling diode, connected to a common pin (COM) used for an inductive kickback voltage protection. This kickback voltage is typically observed at electromotors and relays, so the existence of such a protection makes this driver a good choice for driving motors, relays, and other inductive loads, which can generate back EMF.

Each output is controlled by an input pin. Logic HIGH level on the input will result in the LOW state of the corresponding output, allowing a single driver to sink up to 140mA. The input logic voltage level can range between 1.8V and 5V, thus allowing a wide range of MCUs to be used. The input stage is filtered through an RC snubber filter, allowing the Click board™ to be used in a noisy environment. Logic LOW on the input pin will set the output driver to a HIGH logic level, allowing up to 16V (20V absolute maximum) between the pin and the ground. While in a HIGH state, the output driver will not sink current. For this reason, the input is equipped with the weak pull-down resistor, allowing inputs to be left floating or tri-stated, ensuring that the output drivers will not accidentally drive the connected load.

The output drivers are capable of sinking up to 140mA per channel. However, the DRV777 IC allows outputs to be used in parallel, combining the current that can be sink. This allows sinking up to 1A of current when all the drivers are combined. In addition, more Click board™ can be combined, allowing sinking even more current.

The Driver Click Board™ is equipped with the nine-pole spring terminal. Each output is routed to the terminal, with the addition of the COM pin and GND. This pin is a common cathode pin for all the free-wheeling diodes and a special care should be taken to connect this pin to the same voltage potential as the connected load. If not connected, a permanent damage might occur to the output drivers. GND for the load should be connected to the GND input of the nine-pole spring terminal. By using the output connector, various connections can be implemented with the same Click board™. Drivers can drive relays, motors, or a combination of these. The DRV777 datasheet offers several connecting and driving solutions. It also offers more in-depth information about the IC itself.

Although the IC uses only the 5V power rail from the mikroBUS™, the Driver Click Board™ can be freely interfaced to either 3.3V or 5V MCUs. It does not require a special jumper for the logic voltage level selection. However, it has two SMD jumpers labelled as IN6 and IN7, used to enable or disable these driver inputs. It is done so to prevent eventual interference with the UART module in some cases, as these two pins are routed to the mikroBUS™ RX and TX pins. The complete pinout is contained at the table below.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout of the Driver Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
IN1	IN1	1	AN	PWM	16	IN4	IN4
IN1	IN2	2	RST	INT	15	IN5	IN5
IN1	IN3	3	CS	RX	14	IN6	IN6
NC	4	SCK	TX	13	IN7	IN7
NC	5	MISO	SCL	12	NC
NC	6	MOSI	SDA	11	NC
Power supply	3.3V	7	3.3V	5V	10	5V	Power supply
Ground	GND	8	GND	GND	9	GND	Ground

ONBOARD JUMPERS AND SETTINGS

DRIVER CLICK ELECTRICAL SPECIFICATIONS