TI中文支持网SN74LVC8T245 我们用法是A端固定提供 6V，B端电压可变。
请教问题如下：
1.B端提供最低几V ，SN74LVC8T245 可以正常工作？ （也就是最低几V的电压可以转到6V？）
2.我们在实际使用中发现最低1.1V左右还可以正常转换。请问是为什么？
Seasat Liu：
手册上写的电压是1.65到5.5。超过这个电压之外的，芯片应该不提供保证。
Jerry Xiao：
This 8-bit noninverting bus transceiver uses two separate configurable power-supply rails. The SN74LVC8T245 is optimized to operate with VCCA and VCCB set at 1.65 V to 5.5 V. The A port is designed to track VCCA. VCCA accepts any supply voltage from 1.65 V to 5.5 V. The B port is designed to track VCCB. VCCB accepts any supply voltage from 1.65 V to 5.5 V. This allows for universal low-voltage bidirectional translation between any of the 1.8-V, 2.5-V, 3.3-V, and 5.5-V voltage nodes.
The SN74LVC8T245 is designed for asynchronous communication between two data buses. The logic levels of the direction-control (DIR) input and the output-enable (OE) input activate either the B-port outputs or the A-port outputs or place both output ports into the high-impedance mode. The device transmits data from the A bus to the B bus when the B-port outputs are activated, and from the B bus to the A bus when the A-port outputs are activated. The input circuitry on both A and B ports is always active and must have a logic HIGH or LOW level applied to prevent excess ICC and ICCZ.
The SN74LVC8T245 is designed so that the control pins (DIR and OE) are supplied by VCCA.
This device is fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.
The VCC isolation feature ensures that if either VCC input is at GND, all outputs are in the high-impedance state.
To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver
