Datasheet

Data Sheet AD5251/AD5252
Rev. D | Page 7 of 28
INTERFACE TIMING CHARACTERISTICS
All input control voltages are specified with t
R
= t
F
= 2.5 ns (10% to 90% of 3 V) and timed from a voltage level of 1.5 V. Switching
characteristics are measured using both V
DD
= 3 V and 5 V.
Table 3. Interface Timing and EEMEM Reliability Characteristics (All Parts)
1
Parameter Symbol Conditions Min Typ Max Unit
INTERFACE TIMING
SCL Clock Frequency f
SCL
400 kHz
t
BUF
Bus-Free Time Between Stop and Start t
1
1.3 µs
t
HD;STA
Hold Time (Repeated Start) t
2
After this period, the first clock pulse is
generated.
0.6 µs
t
LOW
Low Period of SCL Clock t
3
1.3 µs
t
HIGH
High Period of SCL Clock t
4
0.6 µs
t
SU;STA
Set-up Time for Start Condition t
5
0.6 µs
t
HD ;DAT
Data Hold Time t
6
0 0.9 µs
t
SU;DAT
Data Set-up Time t
7
100 ns
t
F
Fall Time of Both SDA and SCL Signals t
8
300 ns
t
R
Rise Time of Both SDA and SCL Signals t
9
300 ns
t
SU;STO
Set-up Time for Stop Condition t
10
0.6 µs
EEMEM Data Storing Time t
EEMEM_STORE
26 ms
EEMEM Data Restoring Time at Power-On
2
t
EEMEM_RESTORE1
V
DD
rise time dependent. Measure
without decoupling capacitors at V
DD
and V
SS
.
300 µs
EEMEM Data Restoring Time upon Restore
Command or Reset Operation
2
t
EEMEM_RESTORE2
V
DD
= 5 V.
300
µs
EEMEM Data Rewritable Time (Delay Time
After Power-On or Reset Before EEMEM
Can Be Written)
t
EEMEM_REWRITE
540 µs
FLASH/EE MEMORY RELIABILITY
Endurance
3
100 k cycles
Data Retention
4
100 Years
1
Guaranteed by design; not subject to production test. See Figure 23 for location of measured values.
2
During power-up, all outputs are preset to midscale before restoring the EEMEM contents. RDAC0 has the shortest EEMEM data restoring time, whereas RDAC3 has the longest.
3
Endurance is qualified to 100,000 cycles per JEDEC Standard 22, Method A117, and measured at −40°C, +25°C, and +105°C; typical endurance at +25°C is 700,000
cycles.
4
Retention lifetime equivalent at junction temperature T
J
= 55°C per JEDEC Std. 22, Method A117. Retention lifetime based on an activation energy of 0.6 eV derates
with junction temperature in Flash/EE memory.