TXB0106 Voltage Level Translator Vs 74HC4050 Converter - Non Inverting

Other Hardware General Electronics
1

I'm working with an ATMega328P-PU and want to connect with a GPS and microSD card. Both GPS and microSD run at 3.3 volts while I have the ATMega at 5 volts for the higher clock speed.

I have both 5 volt and 3.3 volt lines on my board. I'm trying to decide between the TXB0106 Voltage Level Translator and the 74HC4050 Converter - Non Inverting. Both GPS and microSD need 3.3 volts on signal lines. Both of the level shifters can bring 5 volts down to 3.3 volts.

I'm wondering if there is a benefit to bringing the 3.3 volt signals coming from the GPS transmitting lines and some microSD lines up to 5 volts to be fed back into the ATMega.

When I use an Arduino, I feed 3.3 volts back in. I would assume with the ATMega I can do the same. Is there a benefit to feeding 3.3 volts or 5 volts back into the chip. For example, higher accuracy in readings or power consumption?

If 3.3 volts is equivalent I will use the 74HC4050, if there is a benefit to the two way level shifter, I'll go with the TXB016.

As always, thank you!

Here are links to the two modules:

txb0106

74hc4050

2

The difference being driving an AVR input at 3.3 volts and 5 volts comes down to one thing. Noise immunity. You could also call it noise safety margin as the 3.3 volt input should work but it's not as robust in a noisy environment as a 5 volt signal.

This becomes more important the faster their data and th further apart the devices are.

The TXB is a unique part, it is bidirectional, not found commonly in bus level translators.

The 74HC4050 is a more conventional single direction buffer.

Unless you need the unique capability of the TXB0108 with a signal that can be driven from either end, either device should work for your needs.