SEN0079 in a 3.3V context?
jd 2016-03-25 15:16:31 3156 Views7 Replies I have recently ordered a LSM303 Breakout Board (SEN0079). I would like to use it in a 3.3V context with a Raspberry Pi. According to the specifications the supply voltage should be at least 3.6V and according to the posted schematic the breakout board should have two voltage regulators on it: one for 3V and for the 1.8V. However, the board that I got has only one voltage regulator on it. Is there an updated schematic? And can the board be used (or modified to be used) in a 3.3V context? Thanks!
2016-04-06 01:38:00
Ok, I've added you as a memo and send it to you once I got it. Leff
jd wrote:Thank you for the offer, Leff. I have sent you a private message with my email address.
Ok, I've added you as a memo and send it to you once I got it.
Leff 2016-04-02 12:00:23 Thank you for the offer, Leff. I have sent you a private message with my email address. jd
jd 2016-03-31 23:45:50 Not yet, sorry.
You can tell me your email address, I could send it to you once I got it at hand. Leff
You can tell me your email address, I could send it to you once I got it at hand.
Leff 2016-03-31 15:42:04 Thank you, Leff. Is the schematic that is consistent with the actual product available? It is not clear to me how the LSM303 would be able to handle higher supply voltages without a second voltage regulator...
Best,
Jochen jd
Best,
Jochen
jd 2016-03-30 22:02:57 I got the reply from related department that this shield schematic was redesigned later when producing, so the schematic is different from the real product.
And I checked its datasheet and application document, that this senser's IIC TTL is less than Vdd+0.1, and our Vdd is 3.3V, so that's compatible with Pi's operation voltage.
Besides, if you have other sensors/ modules woring at 5V or operation voltage is 5V, I suggest you could buy our Pi expansion shield for Arduino
https://www.dfrobot.com/index.php?route= ... ption=true
https://www.dfrobot.com/index.php?route= ... ption=true Leff
And I checked its datasheet and application document, that this senser's IIC TTL is less than Vdd+0.1, and our Vdd is 3.3V, so that's compatible with Pi's operation voltage.
Besides, if you have other sensors/ modules woring at 5V or operation voltage is 5V, I suggest you could buy our Pi expansion shield for Arduino
https://www.dfrobot.com/index.php?route= ... ption=true
https://www.dfrobot.com/index.php?route= ... ption=true
Leff 2016-03-30 08:20:49 Thank you, Leff. The problem is that, according to the schematic, the SEN0079 pulls the I2C bus up to VCC. If I supply it with 5V the I2C bus gets pulled up to 5V, but the Raspberry Pi I2C bus operates at 3.3V. I was therefore planning to either remove or bridge the 3.0V/3.3V (which one is it? The schematic says BL8555-30 and 3.3V...) voltage regulator and to supply the SEN0079 with 3.3V. This is when I realized that there was only one voltage regulator on the board... From taking some measurements it looks like the 1.8V voltage regulator is present and the 3.0/3.3V regulator is missing. This should be perfect for my purpose. I only have to bridge pins 1 and 5 of the missing voltage regulator and I should be good to go, right (assuming that the posted schematic is still applicable to the currently shipped boards)? jd
jd 2016-03-26 00:39:33 Hi Jd,
Pi has 5v output port which allows user to use the module needs 5V power supply, so sen0079 can be compatible. And minimum power supply is 3.5(least).
As to why there is a components missing, I have passed it to the relevant department and will reply as soon as we have a solution.
Btw, I found the chip's datasheet can not be opened, I attached here, and fix that bad link.
Pi has 5v output port which allows user to use the module needs 5V power supply, so sen0079 can be compatible. And minimum power supply is 3.5(least).
As to why there is a components missing, I have passed it to the relevant department and will reply as soon as we have a solution.
Btw, I found the chip's datasheet can not be opened, I attached here, and fix that bad link.
Leff 