1. Detection distance range：50cm-100cm;
2. Detecting angle range: Larger angle up 120°；
3. 4mm glass on the front of the chip.
For the above application，can the SI1153 meet the requirements? What is the acceptance angle of the SI1153?
In addition，How is the lens placed?
I got more than 1.6 degree between readings, is that normal? Since I'm reading the value at 10hz I wouldn't expect this kind of diference.
is that expected?
I have been testing with a national calibration laboratory (Elements) and I have noticed that the Si7021 is only passing 70% of the times (Passing = RH accuracy of >=3%) in temperature of 20c and calibration points 10,50,75% (45 pcs have been tested). None the less I have 100% at 37c (10 devices).
I can't find good data from Silicon Labs about how the accuracy is effected over temperature operating range, only how it is effected over RH range...
Is there a doc that can explain this drop of 30% pass when going to 20c? Is there a way to compensate for it?
To clarify, this is a professional lab making the calibration in a professional RH chamber.
As an example of one of the not passed sensors:
Temp: The chamber ref measured 20.154c and the Si7021 measured 20.16c
Then there were measured 3 humid points:
ref: Si7021: Diff: Uncertainty:
10.16%RH 13.85%RH 3.69 0.16%RH
49.61%RH 50.73%RH 1.12 0.50%RH
74.92%RH 73.95%RH -0.97 0.75%RH
We recently buy the sensor Si117x. However, no datasheet is available.
We have repeatedly asked the local sales office and distributor (Italy zone) how to obtain it by declaring our willingness to sign an NDA but we have never received any answers.
How can we do?
I am using the Si7006 in a very low power application. Power to the sensor is controlled by a load switch. I have seen in the datasheet that tPU is 18ms typical, but it can be up to 80ms depending on temperature. This is much longer than the sensor I am using now (tPUmax = 3ms). How do I know when the Si7006 is ready to take a measurement? Will the I2C bus respond with NACK? Is there a status register I can check for this? Is there a risk if I command a measurement too early that I will get invalid or inaccurate data?
I am working on project with SI1145 sensor on particle photon. Therefore, I want to read visible and IR lower and higher data ( ALS_VIS_DATA0 , ALS_VIS_DATA1,ALS_IR_DATA0 and ALS_IR_DATA1) . I changed little bit library to read lower and high data,
We are currently using the Si1141-M01-GMR sensor module.
However, since some time this sensor is not recommended for new designs.
Therefore, we look at the Si1153-AB9x-GMR sensor module.
The old Si1141 can sample with a period of 3 x 31.25us = 93.75 us (about 10.000 Hz)
To achieve this, we set the MEAS_RATE register to 0x18 (page 39 of datasheet). The uncompressed number is then 3.
The new Si1153 seems to be limited to a period of 1 x 800us = 800us (about 1.000 Hz)
The minimum time between measurement groups seems to be 800 us (see page 35 of datasheet)
Is it true that the maximum sample rate of the new sensor module is a factor 10 slower?
Or do we miss something?
Furthermore, at mouser, the new sensor module is about 50% more expensive.
And the programming is not backwards compatible.
Data is read after sending command 0xE5 "Measure Relative Humidity, Hold Master Mode"
Data is read after ~ 10 msec. MSB bits are always high in room temperature. Now when I head teh sensor, MSB bits becomes low.
For eg: I get 0xFF7A from sensor when the another reference Humidity Meter reads 65% RH.
Now when I heat Si7020 sensor and the reference sensor meter , 7020 returns 0x0052 where as the meter reads 57%.
When RH is calculated based on the equation provided in datasheet the sensor data is totally wrong.
Please see the attached oscilloscope images.
Appreciate any help to debug this.
I have two questions on the "Si1143-A11-GMR Proximity/Ambient Light Sensor IC with I2C Interface"
1) Can you tell me whether the external layer of the top and side of the package is biocompatible?
If yes, do you have some document/statement to proof this?
2) The height is of importance in our design and I notice that the tolerance on it is quite high 0.65 ± 0.10. Is there any way this can be reduced? Or maybe could you give me some distribution / typical values?
Thanks in advance for your support!
I am a student currently working on a project where I would like to read out humidity and temperature data from the Thunderboard Sense 2. This board has an on-board SI7021 chip. I tried to use the humitemp example as a template but that example is for a SI7013. I found the SI7021.c and SI7021.h files in the demo's of the Thunderboard Sense 1. I am assuming that those are identical for the Thunderboard Sense 2.
When trying to read out data, I keep getting error codes 1 and 2 ("SI7021_ERROR_I2C_TRANSFER_NACK" & "SI7021_ERROR_I2C_TRANSFER_FAILED").
Is it possible to describe in some basic steps what the code should do? I don't really know when (and if) I have to initialize the internal I2C bus.
I am also unsure about where to post this question. I think this is the best place, since my problem is with the SI7021 chip.
Thanks in advance!
This forum is for support for the following products only:
Optical sensors -
RH/Temp sensors -
Problem is exactly as stated.
Following the directions using the Si115x EVB part does not work. I get various error messages. When I go to the Si115x Control Panel and hit "Sommit Settings View Waveform" I get the error message "Unable to communicate with EVB" When I choose any demo from the drop-down list in the Si115x Main Panel is hit LAUNCH DEMO, a window pops up saying "Configuring Part..." but then an error window follows: "Demo Execution Error! Please select the UV/ALS DIP Switch and power cycle the board"
I do all this a dozen times, for each demo, same error message every time.
I have the correct DIP switch settings. It doesn't matter which one I use; they are do not function at all.
Please help. This is already very frustrating. Your website is impossible to search correctly. Search results having nothing at all to do with this EVB or Si115x. Software seems scattered all over the place without any up-to-date central repository.