8 Logic Channels, Single Supply, Bidirectional Voltage Level Shifter RT-NVT2008

Description

RT-NVT2008 is a bidirectional voltage level translator. Converter pass the signals in both ways from high to low and from low to high without need to control the signal direction.
Input power supply voltage drives a high voltage side (VrefB) and a low side voltage regulator (VrefA) which can also be sourced on VL pin. Low dropout regulator used to supply the low voltage side allow minimum difference between VrefA and VrefB to be as low as 1.2V.
We are supplying the boards with one of the 1V/1.2V/1.8V/2.5V/3.3V/5.0V regulator. Voltage of the regulator should be selected for the low side voltage. Depend on the application not all configurations of the high and low side voltages can be achieved. Minimum voltage difference between B and A must be more than 1V:

(V_Input_B - V_Input_A) >= 1.2V.

Because of that maximum voltage allowed depend on the input:

• low side input A is constrained by chosen voltage regulator and can vary from 1.0V to 3.3V,
• high side input B is constrained to supply voltage and can be as high as 5.0V

See comparison of the correct voltages in the table below:

A – Allowed configuration
P – Prohibited configuration. It won’t work.

Multpile channels voltage level translator can be used with the interfaces: SPI, I2C/TWI, UART or standard logic IO. Example system configurations are showed in the picture: