- Apr 5, 2023
In model GH-40-52 ROM MX23L6400AYC-10G 100ns. I soldered in GH-72-42 MX29LV320ATTC-90 90ns. Works!Valid data output after OE# low 30ns;
AFAIK this is only true when the chip receives the address min. 40ns before OE goes LOW, as the max 70ns access time (address->output) is still there. You can see it in the timing diagram in the datasheet. Correct me if I'm wrong though!
The EE outputs the 22 bit address almost synchronously with OE. According to my captures, the addresses are output about 10ns (average) before OE goes LOW, after that the MX29LV320ETTI-70G still needs max 60ns to output valid data. The smallest OE low pulses I've seen are about 120ns-140ns long.
The only open question here is where the EE reads the data within those 120-140ns. If the EE reads them in the center of the pulse, the timing might be very tight in some situations and that's my only explanation for the MX29LV320ETTI-70G not working.
I could give my CE fix a try to see what happens, but as the mainbaord did not even boot with this chip I don't have much hope!