DRV8844EVM: Motor Drivers Forum

Mehmet Tomac

Part Number: DRV8844EVM

Hi. I'm trying to use DRV8844EVM to drive four 24V DC 1A (Festo MH3) solenoid valves. I'm generating four square waves (this wave has frequency, duty cycle, phase info in it already) in LabView and use its analog outputs to provide the control signal to DRV8844EVM. Here are couple questions that I'm trying to solve:

1- I will take the jumpers off from J3 for four inputs (IN1 to IN4) and put my square wave analog signals positive voltage (only at driver's side not microcontroller side) but what am I supposed to use as the ground for these analog signals? Just LGND may be?

2- Similar problem with the output from DRV8844EVM. How am I going to ground the output voltages that are going to solenoid valves from DRV8844EVM?

3- There are test stakes on DRV8844EVM. These are provided for measurements with probes for sure. What is the easiest way to connect a cable on these? Just hold o cable touching it and then solder?

Thank you very much for the help!

over 6 years ago

0 James Lockridge19 over 6 years ago

TI__Genius 14485 points

Hi Mehmet,

Before I can answer questions 1 and 2, can you tell me about the VM supply for the board? What supply voltages are you connecting to VM+ and VM-?

3) The test points on the board are designed for spring-loaded hooks. These are sometimes called "minigrabbers."

0 Mehmet Tomac over 6 years ago in reply to James Lockridge19

Prodigy 50 points

Hi James,

I will be using a power supply with output 24V DC at 2.5A.

Thank you very much.

Mehmet

0 James Lockridge19 over 6 years ago in reply to Mehmet Tomac

TI__Genius 14485 points

Mehmet,

1) The ground for the NI DAQ can connect to LGND or VM- since these should both connect to your power supply ground. If you supply a negative voltage to VM-, then only connect the NI DAQ to LGND.

2) You can connect your valves between the OUTx pins and your power supply ground if you are only turning the valves on and off. If you need to run the current in both directions through the valve coil, then connect the coil between two OUTx pins and provide the proper signal inputs to the IN pins to change direction of current flow.

0 Mehmet Tomac over 6 years ago in reply to James Lockridge19

Prodigy 50 points

Thank you very much James! Since I'm using a single power supply J2 is in place connecting VM- and LGRD.

Motor drivers

Motor drivers forum

DRV8844EVM: Motor Drivers Forum