Hi, dialog. Recently I am measuring the power consumption of my custom board which has some sensors on it. I double check that I have set the correct sleep mode of all sensors, and disabled uart and jlink interface also. But when I measure the current with one 10 Om resister using oscilloscope, the result is as high as 160ua. Could you please give me some suggestions on how to find the wrong place? Thanks.
Device:
嗨，Summer，160uA是a吗constant, average, or peak ? is it noisy or clean ... If you probe around the DA14580, do you see any activity on any GPIO etc ? Also, 10Ohm might be a bit high : can you take a look at section 4.1 of the below document ?
http://support.dialog-semiconductor.com/system/files/resources/AN-B-015_...
BR JE_Dialog
Hi, the 160uA current is constant which is the offset of the measured result. I have read the doc before, but I'm still confused about the high measured current. Maybe there is something wrong with my board? But I double check the schematic all day long yesterday and unfortunately, don't make any progress.
你好，你提到了吗hte 160uA is an offset : so is the 1.6mV there even if you disconnect the supply completely ? i was wondering if you are seeing 1.6mV of offset/noise on your measurement circuit. On a 10 Ohm resisors, what looks like 160uA is only 1.6mV which could be offset/noise. BR JE_Dialog
Thank you for your reply, but I measure another board which is the BLE product of one company China, there is no offset current.
OK.. no problem. I will send you a message and have one of the team take a look at this : we'll need your schematics and a scope waveform of what you are seeing. BR JE_Dialog
OK, I have emailed you and I am appreciated about your work, thanks.
看起来电流是由i2c接口引起的，但是我确信我已经设置了连接到i2c总线的传感器的正确的低功耗模式。你觉得怎么样？
Hi Summer,
连接到Vbat3的I2C上拉电阻器（1K）可能是泄漏电流的来源。
When in sleep, are the SDA and SCL lines indeed high-impedance?
Are you able to measure the Vbat3V current of the DA14580 device alone?
SPI闪存设备消耗了多少电流？
不使用时蜂鸣器真的完全关闭了吗？
Best regards, BB_Dialog.
嗨，谢谢你的建议。卸下SPI闪存和上拉电阻器的Vbat3V电源后，电流为90ua，卸下SPI闪存、lis3dh、bme280和上拉电阻器的Vbat3V电源后，电流降至1.5ua。我也做了更多的测试，但我不打算描述那些乏味的细节。现在我有一个问题，如何设置SDA和SCL线路的高阻抗？据我所知，大电流可能是由以下两种来源之一引起的：i2c总线或lis3dh，但我现在还不能弄清楚。所以请帮我推进，谢谢。
Hi Summer,
the I2C lines should be in high impedance state when the DA14580 is in sleep mode, they will not draw current.
Best regards, BB_Dialog.
但是当我测量卷tage of the SCL and SDA pin, the result is as high as the Vbat3V level. And what's more, it is said that DA14580 will latch the pin status when in sleep mode, and i2c bus is idle high, so the result I get may be correct. So is there anything that I am wrong ?
Hi Summer.
when measuring SCL and SDA levels as high as Vbat3V, it indicates there's no current throught the pull-up resistors. Pins are high.
All is okay in our opinion.
We think you have to look for current leakage in the other devices.
Best regards, BB_Dialog.
好的，我只想确认，即使没有上拉电阻，SCL和SDA的电平也高达Vbat3V，是真的吗？因为我已经拆下了上拉电阻。
Hi Summer,
yes, we would expect that.
In this state, you do mesasure the 1.5µA sleep current?
Best regards, BB_Dialog.
It's weird to me. After I remove the pull-up resistors and the Vbat3V supply of LIS3DH without initializing the i2c interface, the current is about 13ua. But if I enable the i2c interface, the current is as high as 100ua.
After I remove the LIS3DH from my board completely, it seems that the current returns to normal. So my question here is, what should be taken care of when I use LIS3DH ? It seems the LIS3DH worked well before in spite of the high current.
I changed the accelerometer LIS3DH with KX022, and the current is below 10 ua now.
Hi Summer, thanks for letting us know that you fixed the issue. I'm surprised the LIS3DH doesn't work as its very popular product and we have multiple customers using it with the DA14580.. The KX022 looks like a good device ! BR JE_Dialog