Right on the front page of the TI data sheet are the words:
“Reverse applied voltages of up to 20V will draw only a few dozen microamperes of current, allowing the devices to act as both a rectifier and current source in AC applications.”
Which is absolutely brilliant if you are trying to save a diode drop as you can replace two of the diodes in a bridge rectifier with LM334s and you have a current-regulated output bridge rectifier.
