Hi, I am doing a test of consumption and I do not match the values with those specified on the TI datasheet. The pins are connected like this:
GND pin to GND
VCC pin to 3.6V
nSLEEP pin to GND
PHASE pin to GND
ENABLE pin to GND
GND pin to GND
VIN pin to 3.6V
OUT2 pin no connect
OUT1 pin no connect
VM pin no connect
The measured consumption is between 250 and 270 uA when the datasheet specifies a maximum consumption of 120 nA. I have done the test with two different DVR8838 What am I doing wrong? Thanks in advance.
The amount of current you are measuring seems like it could be normal for how you are using the board. There is a 10k pull-up resistor on the nSLEEP pin that dominates the quiescent current draw of the board when the pin is driven low to put the driver to sleep. If you want to lower the quiescent current draw of the board, you can remove that pull-up resistor. Below is a picture of the top of the board that I’ve circled the pull-up resistor on:
Thanks for your answer Jonathan. The consumption is less than 1uA with resistor removed, in the test configation given by franmartin.
Nevertheless, when I connect the Sleep pin to my microcontroler, it comsumes 1.1A.
Pins connexion
GND to GND
VCC to 3.6V
nSLEEP to MC PIN in Digital Ouput Low.
PHASE pin to GND (or no connect, same result)
ENABLE pin to GND (or no connect, same result)
GND pin to GND
VIN pin to 3.6V
Can you verify that when you say “The consumption is less than 1uA with resistor removed, in the test configation given by franmartin”, you are saying that you measured the current draw of the DRV8838 with nSLEEP connected to GND?
The nSLEEP pin should already be pulled low, so it is strange that it would draw any more current when connected to a microcontroller pin driving low. Can you verify that your MCU pin is actually being driven low? Can you also send pictures that clearly show your connections and setup?
