LSF0101: Level Shifter

Tejas Neelakanta

Part Number: LSF0101

Hello,

We are using 21 Level Shifters (LSF0101DRYR) for level shifting between 3.3V to 5V. The output voltage from the regulator(TPS73233DCQ) which is 3.3V output is providing 3.9V while we populate all the 21 level shifters but if we populate less than 6 Level Shifters the output of the regulator is 3.3V. Can anyone suggest any solutions?

over 2 years ago

0 Clemens Ladisch over 2 years ago

Guru 243790 points

A small current flows into Vref_B and out of Vref_A; it is limited by the 200 kΩ resistor. (See [FAQ] How do the LSF translators work?) The lower supply must be able to sink this current; if not, it might float up.

Add a load to the 3.3 V supply. A 22 kΩ resistor between 3.3 V and GND should be enough.

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LSF0101: Level Shifter