SN65HVDA1040A-Q1: What's the difference between SN65HVDA1040AQDRQ1 and SN65HVD1050AQDRQ1 ?

Xiaofu,

The only difference between these two devices is the function of pin 8. Pin 8 on the 1040 places the device in standby when the pin is driven high, which disables to the bus driver and receiver and causes the device to consume much less overall current. Pin 8 on the 1050 places the device in silent mode when the pin is driven high, which disables the bus driver but leaves receiver enabled. 

Please let us know if you have any other questions.

Regards,

Eric Hackett