Rainbow Electronics DDS1693 - Manual (Page 25)

DS1689/DS1693
25 of 32
DS1689/DS1693 BUS TIMING FOR READ CYCLE TO RTC
RTC AC TIMING CHARACTERISTICS
Over the operating range (5V)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Cycle Time t
CYC
305 DC ns
Pulse Width, RD / WR Low
PW
RWL
125 ns
Pulse Width, RD / WR High
PW
RWH
150 ns
Input Rise and Fall Time t
R
, t
F
30 ns
Chip Select Setup Time Before WR , or RD
t
CS
20 ns
Chip Select Hold Time t
CH
0 ns
Read Data Hold Time t
DHR
10 80 ns
Write Data Hold Time t
DHW
0 ns
Muxed Address Valid Time to ALE Fall t
ASL
30 ns
Muxed Address Hold Time from ALE Fall t
AHL
10 ns
RD or WR High Setup to ALE Rise
t
ASD
25 ns
Pulse Width ALE High PW
ASH
60 ns
ALE Low Setup to RD or WR Fall
t
ASED
40 ns
Output Data Delay Time from RD
t
DDR
20 120 ns 9
Data Setup Time t
DSW
100 ns
IRQ Release from RD
t
IRD
2 ms
CEI to CEO Delay
t
CED
10 ns