ADC1225 datasheet(12/18 Pages) NSC

12 / 18 page

Functional Description (Continued)

TLH5676 – 28

TLH5676 – 29

FIGURE 13

When using this method of conversion only one strobe is

necessary and the rising edge of WR RD can be used to

read the current conversion results These methods reduce

the throughput time of the conversion since the RD and WR

cycles are combined

2 With the standard timing WR pulse width longer than the

conversion time a conversion is completed but the INTR will

never go low to signal the end of a conversion The output

latches will be updated and valid information will be avail-

able when the RD cycle is accomplished

3 Tying CS and RD low continuously and strobing WR to

initiate a conversion will also yield valid data The INTR will

never go low to signal the end of a conversion and the

digital outputs will always be enabled so using INTR to

strobe the WR line for a continuous conversion cannot be

done with this part

A simple stand-alone circuit can be accomplished by driving

WR with the inverse of the READY OUT signal using a sim-

ple inverter as shown below

TLH5676 – 30

FIGURE 14

ADC1225 Datasheet(PDF) 12 Page - National Semiconductor (TI)