DRV2605 and EN pin

Should I2C communications function no matter what state the EN pin is in? Or does it have to be set high (tie to VDD)? When I scan the I2C bus I can see other devices, but not the DRV2605? I'm using an Arduino Mega as MCU for basic testing at the moment. 

Hi, Robert:

the device's I2C communication function is working even if the device is in standby state.

but if the device is in standby state, writings to a lot of registers will be ignored (reading is OK).

For normal operations, EN pin needs to be high and STANDBY bit should be cleared.

if drv2605 is not found(no ACK when I2C host issues address 0x5a? ), please check the EN pin voltage level.

if possible, please check the data on I2C bus when I2C host issues address 0x5a.

Hi Peter,

I'm having similar issues. I'm attempting to communicate with the DRV2605 over an I2C bus that I am successfully using to talk to other chips at < 400kHz . So i know my I2C driver is ok and when monitoring the I2C bus (with an Aardvard I2C/SPI total phase device) I see that the messages I'd like to be sending are in fact on the bus, but the DRV2605 is not acknowledging any of them.

I have checked the voltage level of the enable pin (3.2V) and the first message that I attempt to write to the chip is to the MODE register to remove the chip from STANDBY mode.

Do you have any advice about what else I could check?

Thanks,

Megan

Hi, Megan:

under normal operations, if the EN pin is high, no matter the STANDBY bit is set or not, the DRV2605 will acknowledge any I2C commands sent to it, but maybe ignore actions the commands want.

i think the checklist maybe:

1. I2C slave address on the I2C bus ----- is it 0x5a?
2. the voltage on  Vreg -- is it about 1.8V?
3. the voltage on VDD?

it the above two items are all normal, then the issue maybe hide in the board I2C connection to DRV2605.

what DRV2605 board are you testing with? DRV2605EVM-CT? DRV2605-miniEVM?

I recommend the DRV2605-miniEVM as it is in simple hardware environment.

if you are working with DRV2605EVM-CT, we need to check the below items:

1. JP2 is enabled or not? what is the voltage level of SDA-IN/SCL-IN pin before connecting to I2C master?
2. can the DRV2605EVM-CT alone work as described in the UserGuide? when the EVM-CT is power on, the board will be initialized and actuators will be calibrated (we can feel the vibration). 

please check the above so as to have more clues for further analysis.

Hello Peter,

Do you have a link to the DRV2605-miniEVM? I've just received a DRV2605EVM-CT and will start some testing with it. I'm in the same situation as Megan.

Hello Megan,

What Host device are you using to communicate with the DRV2605? I've been wondering about pull-up resistor values and the DRV2605. I have a few new "host" setups to try out in the next week or so to gather more information.

Thanks

Robert...

Hi Peter,

I have a custom PCB with the DRV2605 on it. I'm attempting to communicate with it from a dsPic33.

As far as your questions go...

1. Yes I am trying to send communications to device ID 0x5a. I write 0xB4 (0x5a shifted with LSB as 0 for write).

2. I see 1.8V on the Vreg pin

3. The voltage on VDD is 3.2 V.

Here is a schematic of the connections. M_EN2 & M_TRIG2 are just GPIO from the uController. SDA and SCL are the I2C bus which is successfully communicating with other devices...so I'm sure it's working correctly at <400kHz.

Thanks for your responses!

Megan

Hi, Megan:

I cannot see the schematic you posted.

By now I have no idea about why the DRV2605 doesn't respond.

I think we should check the components and connections around the chip.

If you can get the DRV2605-miniEVM (maybe Brian can help), maybe we can check with the mini-EVM.