DRV110: DRV110 solenoid driver switching problem

Hi Chetan,

Thanks for your question. Let me contact the expert for this part. You can expect a response by 3/9/20.

Best,

Grant

Hello Chetan,

If you see a significant delta current between valves that's leakage current on the sense resistor or/and Rpeak or Rhold.

The delta current is same(%) for Ipeak and Ihold?  If the ratio is same very likely is Rsense.

Do you see IR drop between DRV1_GND to DRV2_GND?

The reference GND for Rpeak/Rhold/Rsense needs to be each DRV110 GND pin.

Regards,

Costin

Hello Costin,

I have connected all the grounds together including both the DRV grounds, please refer to the attached document for connections and LTspice simulation for valve currents.

Coil1= On Coil2 = OFF

Fig 1: circuit block dia

Fig2: Coil switching for the alternative signal 

Fig3: coil switching parallelly 

Checked voltage drop at Peak and hold resistor during parallel switching and both are same

Hello Chetan,

That's a current leakage to GND from Peak pin and Hold pin to GND. Did you tried without the common pot?

Replace the pot with a fixed resistor, one for each DRV110. The Peak and Hold threshold is set by the Peak_pin/Hold_pin to the GND_pin.

Another suggestion for debugging the issue is to increase the keep time and the total on time

Regards,

Costin

Hello Costin,

I want to control the current in both the coils by just using one Pot (2 pots, for peak and hold) and this set up is working fine when drv is getting triggered alternatively.

Is there any method to control peak and hold currents of multiple DRV's by using a single pot?

Regards,

Chetan

Hi Chetan,

I don't see any issue using one pot for both, the singe fix resistor to GND pin suggestion is for debugging.

What I don't understand is the slow current rise time, it looks like low coil voltage

Regards,

Costin.