TXS0102-Q1: VIH issue

John Man

Part Number: TXS0102-Q1
Other Parts Discussed in Thread: TXS-EVM

Tool/software:

Dear sir,

In TXS0102-Q1 datasheet, VIH(Ax) and VIH(Bx) are required to be min. VCCA-0.2 and VCCB-0.4 respectively. However, for a CMOS &TTL input signal, the logic high is normally VCC*0.65 (min.).

Why does TXS0102-Q1 require a min. VIH voltage as high as VCCA-0.2 and VCCB-0.4 ? This can not be achieved by CMOS & TTL input logic.

Such request prevents me using TXS0102-Q1 as a level shifter.

Pls advise.

Thanks

John

7 months ago

0 Clemens Ladisch 7 months ago

Guru 317390 points

The V_OH(min) of a logic device is specified for a certain output current. But the TXS does not sink any current (in fact, the pull-up resistor also pulls the line high), so the output current will be zero, and the actual V_OH will be V_CC. See [FAQ] What is the output voltage (VOH or VOL) when the output current is X or the supply voltage is Y?

0 Tyler Townsend 7 months ago

TI__Mastermind 48338 points

Hi John,

Our engineer who supports these devices is currently ooo. Please allow us to get back to you on Tuesday next week.

Regards,

Tyler

0 Jack Guan 7 months ago

TI__Mastermind 41256 points

Hi John,

Clemens is correct here (the VIH spec in the datasheet is pessimistic here)- please let us know if any additional concerns arise. You may also see the TXS-EVM for device evaluation: www.ti.com/.../TXS-EVM

Regards,
Jack

Logic

Logic forum

TXS0102-Q1: VIH issue