AD8333 IQ demodulation IC question

In the datasheet of the AD8333 is says that the minimum square wave "LO Frequency Range" is 10 kHz. Does this mean that it needs a minimum 10 kHz square wave to be able to do the IQ demodulation? So if I were to use a 1 kHz signal to be mixed (which is supported, DC to 50MHz) I would have to provide the IQ demodulator with a 10 kHz square signal? If so, how does the chip calculate the I and Q component from this?

After reading the data sheet I thought that I would send a same frequency sinusoidal and square signal to the chip with some phase difference between 0 and 90 degrees, and I would get the corresponding I and Q values?