BQ2204A Datasheet, PDF (6/12 Pages) Texas Instruments – X4 SRAM Nonvolatile Controller Unit

bq2204A
AC Test Conditions
Parameter
Input pulse levels
Input rise and fall times
Input and output timing reference levels
CECON
510
Test Conditions
0V to 3.0V
5ns
1.5V (unless otherwise specified)
5V
960
100pF
FG220102.eps
Figure 3. Output Load
Power-Fail Control (TA = TOPR)
Symbol
Parameter
tPF
VCC slew, 4.75V to 4.25V
tFS
VCC slew, 4.25V to VSO
t_PU
V_CC slew, 4.25V to 4.75V
tCED chip-enable propagation delay
tAS
A,B set up to CE
tCER chip-enable recovery
tWPT Write-protect time
Minimum
300
10
0
-
0
40
40
Typical
-
-
-
7
-
80
100
Maximum
-
-
-
10
-
120
150
Unit
Notes
µs
µs
µs
ns
ns
Time during which SRAM is
ms write-protected after VCC
passes VPFD on power-up.
Delay after VCC slews down
µs past VPFD before SRAM is
write-protected.
Note:
Typical values indicate operation at TA = 25°C, VCC = 5V.
Caution: Negative undershoots below the absolute maximum rating of -0.3V in battery-backup mode
may affect data integrity.
Dec. 1992 B
6