LAVA OTG adapter keeps android tablet from sleeping
The LAVA SimulCharge has a chip in it that detects if charge power is being supplied.  If no charge power is being supplied it turns into a regular OTG connection.  When it does this, it draws power from the tablet to power your accessories.

From what I've looked at so far, I haven't found a way to make the OTG 5V power from the tablet turn off when the tablet goes into sleep mode. When the tablet goes to sleep, it seems to still be providing the OTG power.

My tablet will go to sleep, but drains the battery from the OTG connection.