Level shifter board to adapt 5V logic to 3.3V logic. The typical use is to interface an existing or new 5V AVR / PIC / MCU project to new devices that use 3.3V logic, like SD cards, Lantronix XPORT devices, Wiznet modules (Wiznet modules have 5V tolerant I/O pins), etc.
This board in a standard 600mil DIL package carries a 74LCX245 IC and 2 pull-up / pull-down resistors.
The IC is configured to enable output (OE pin pulled down) and the direction is A to B (DIR pin pulled up). You can manage the OE and DIR signals by applying the desired logic value to these signals. A0-A7 to B0-B7.
You just connect the 5V logic signal to any port A and you obtain the same signal at 3.3V logic on port B.
You can add a 0.1uF ceramic decoupling capacitor between the 3.3V and GND pins