VNH2sp30 output current is too low

I use VNH2sp30 to driver a coil.I use a switch power 12v 2A as VCC for power supply,and connect +5v、GND to control board,connect INA to 5v,NB to GND on control board.But i found that the output of VNH2sp30 is about 6v and the current is about 0.4a. VNH2sp30’s current can up to 14a,why the current I got is too low? Why this problem occuered, is this because the switch power current not high enough? Thanks

I use vnh2sp30 to drive a coil.The power supply is 12v 2a.But I found that the output is only about 6v,current is about 0.4a.So why does this problem happened?


You did not give us enough information to know how much current your coil should draw. What coil are you using? Is it a motor or just a coil? What is its resistance? How are you measuring the voltage and current of the coil? Also, what are you doing with the PWM pin? Could you post pictures of your setup that show how everything, including your power supply and coil, are connected?


I use dsp to control the vnh2sp30. First,to test vnh2sp30 board I connect it like this.
Motor Supply + ------->Power 12v;
Motor Supply - ------->GND;

In this situation I think the output measured by DMM should be about 12v,but it about 6v.So what is problem? Did I connect wrong?

Thanks for posting the wiring diagram. I do not think that it is causing your issue, but you should not connect the DIAG/EN pins to 5V. These pins are only meant to be pulled to ground to disable the board or used as inputs to tell when there is an error. I also noticed that you did not list the PWM pin when you described your connections in text, but it is shown connected to 5V in your diagram. What is the PWM pin connected to in your setup? Could you measure the output of your 12V supply to make sure it is 12V? Could you also check the 5V output of your DSP while it is connected to the driver? When you measured the output of the driver, did you have your coil connected? Could you post pictures of your physical setup?


Oh,I make a mistake on the picture,I have just check the connection the DIAG/EN is connected as you said,and the input volt is 12v.I just found that if change the connection of INA and INB,just like this:
the output can reach 12v. So I don’t know why this happened,does the output of VNH2sp30 related with this?


It sounds like the behavior you are describing is normal (e.g. getting 12V out when INA is connected to logical low with INB and PWM connected to logical high). Could you try switching the INA connection back to 5V and the INB connection back to ground to see if the output stays at 12V (with the opposite polarity) as expected? If it does not, could you post pictures of both cases that show all of your connections?