AL422B Speed Limits - Write Clock Up to 2 MHz

[Ravaner]

Hello. I use a Fifo IC AL422B with a 1 MHz write clock and a 625 kHz read clock. I just discovered that 1 MHz is the low speed limit for the clocks. I can speed up the write clock to 2 MHz but unfortunately I can't change read clock speed. As these clocks ( or at least one of them) are used for refresh cycles, do you think that increasing write speed will be sufficient to insure a proper way of work ?

 

[berkeman]

Hello. I use a Fifo IC AL422B with a 1 MHz write clock and a 625 kHz read clock. I just discovered that 1 MHz is the low speed limit for the clocks. I can speed up the write clock to 2 MHz but unfortunately I can't change read clock speed. As these clocks ( or at least one of them) are used for refresh cycles, do you think that increasing write speed will be sufficient to insure a proper way of work ?

The datasheet says it is self-refreshing, so that doesn't look like an issue:

http://www.google.com/url?sa=t&rct=...ho38Bg&usg=AFQjCNGXkWLiJRGbk02mfBrMh3_TOy7rIA

However, it appears to have the same specs for both the Write and Read clocks -- 20ns to 1us period. You aren't going to be able to read it at 625kHz if I'm reading that specification correctly.

Do you have the circuit working at 625kHz?

 

[Ravaner]

Thanks for reply. Reading is done by an old PC (300 MHz) through Centronics // interface and I've no way to increase this speed