Make sure LV is powered at 3.3V, and HV is at 5V. Double-check that the
channels match up, and a-shifting you will go! You’ve even got two extra
channels to shift as you please.
Using the BD-LLC for SPI
The BD-LLC’s four channels are a perfect match for most SPI
communications. SPI usually requires four wires: MOSI (master out, slave
in), MISO (master in, slave out), SCLK (serial clock), and CS (chip select).
These four wires can each be routed through a channel on the BD-LLC.
For example, if you wanted to connect an Arduino to an ADXL345 Breakout
Board, which has an operating range of 2.0-3.6V, here’s how the BD-LLC
could be spliced in:
Since each of the channels on the BD-LLC are bi-directional any of the four
SPI lines can go through any of the BD-LLC’s four channels.
Using the BD-LLC for I C
I C is the communication standard where the BD-LLC really shines,
because it requires that both data and clock signals – SDA and SCL – be
bi-directional. Each of those lines can be passed through any of the BD-
LLC’s level-shifting channels.
For this example, let’s keep using the ADXL345 breakout but instead swap
over to the I C interface. We can even add another I C device…how about
the L3G4200D Gyroscope Breakout. Since I C is only a two-wire interface,
we have room on the BD-LLC to fit in a couple of extra signals, like the
interrupt outputs from each board
The two 3.3V I C devices can both share the same level shifted SDA and
SCL lines. Even more I C device can be added, as long as they have
unique addresses.
2
2
22
2
2
2
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