information about AD7503JNZ in the datasheet.
The only difference the J model and the K model is the Vih spec. For the J
model it is 3V min and the following note applies - A pull-up resistor,
typically 1-2kOhms is required to make the J models compatible with TTL/DTL
levels. The maximum value is determined by the output leakage current of the
driver gate when in high state.