Need spec for SFR02

[gregory.cris]

Hello,

I am looking for some technical specs on you SFR02. The issue I have is that the SCL and SDA lines for the I2C are pulled-up to 3.3 V.
The SFR02 is supplied in 5V. At the moment, the I2C comm is not working, the device address is acknowledge but not the reg address. I tried to read or write without effect. Is it possible to have the electrical characteristics for the SFR02 module?

Thanks in advance,

Gregory

[Gerry]

Hello,

I am looking for some technical specs on you SFR02. The issue I have is that the SCL and SDA lines for the I2C are pulled-up to 3.3 V.
The SFR02 is supplied in 5V. At the moment, the I2C comm is not working, the device address is acknowledge but not the reg address. I tried to read or write without effect. Is it possible to have the electrical characteristics for the SFR02 module?

Thanks in advance,

Gregory

Minimum input high voltage is 0.8Vdd or 4v for the 5v powered SRF02. (PIC16F687 spec's).
You should drive the SRF02 with 5v signal levels, or use a 3.3v controller with 5v tolerant inputs and pull up to 5v.

[gregory.cris]

Thanks for the quick reply. I had a quick look on the PIC16F687 spec sheet. I am thinking to drop down the supply voltage for the SFR02 to 3.3v.
On page 233 of the datasheet (http://ww1.microchip.com/downloads/en/D ... 41262E.pdf), its says that this should be working if Fosc is less than 20MHz.
Can I assume this to be OK?

[gregory.cris]

sorry, It is OK if Fosc < 10Mhz. Can I assume this true?

[Gerry]

Thanks for the quick reply. I had a quick look on the PIC16F687 spec sheet. I am thinking to drop down the supply voltage for the SFR02 to 3.3v.
On page 233 of the datasheet (http://ww1.microchip.com/downloads/en/D ... 41262E.pdf), its says that this should be working if Fosc is less than 20MHz.
Can I assume this to be OK?

The SRF02 is charaterised and warranted for 5v use.
The few we have tested at 3.3v work but with reduced range and sensitivity.