LSF0102: Is that leakage from VerfB to VerfA?

zhang ping

Part Number: LSF0102
Other Parts Discussed in Thread: LSF0002,

Tool/software:

① After measurement, the LSF0102DCTR level conversion chip will leak from the high level of the VerfB terminal to the low level of the VerfA terminal. When the VerfB is 3.3V, the EN pin should be connected to 3.3V according to the chip manual. If there is no load, the VerFA terminal should have a voltage of 1.8V, but the measured voltage is around 2.1V. After removing my LDO chip, the voltage is around 2.4V. Is that leakage from VerfB to VerfA? My circuit is like this:

6 months ago

0 Clemens Ladisch 6 months ago

Guru 317450 points

There indeed is a leakage current during normal operation.

Add a resistor of 220 kΩ or less between Vref_A and GND. For details, see section 8.1.7 of the datasheet.

The LSF0002 would be easier to use.

0 Jack Guan 6 months ago

TI__Mastermind 41266 points

Hi Zhang,

Clemens' recommendation is correct here. LSF0002 can be utilized here with only one power supply (1V8) to the device. On the LSF0102, there is a leakage from VREFB to VREFA that is limited by the 200kohm, which the power supply on A-side must be able to sink. Not all LDOs are capable of this, hence the voltage readings that you observe here.

Regards,

Jack

Logic

Logic forum

LSF0102: Is that leakage from VerfB to VerfA?