CY7C197 Datasheet, PDF (4/10 Pages) Cypress Semiconductor – 256Kx1 Static RAM

CY7C197
Switching Characteristics Over the Operating Range^[6]
7C197-12 7C197-15 7C197-20 7C197-25 7C197-35 7C197-45
Parameter Description Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Unit
READ CYCLE
t_RC
Read Cycle Time 12
15
20
25
35
45
ns
t_AA
Address to
Data Valid
12
15
20
25
35
45 ns
t_OHA
Output Hold from 3
3
3
3
3
3
ns
Address Change
t_ACE
CE LOW to
Data Valid
12
15
20
25
35
45 ns
t_LZCE
CE LOW to
Low Z^[7]
3
3
3
3
3
3
ns
t_HZCE
CE HIGH to
High Z^{[7, 8]}
5
7
0
9
0 11 0 15 0 15 ns
t_PU
CE LOW to
0
0
0
0
0
0
ns
Power-Up
t_PD
CE HIGH to
Power-Down
WRITE CYCLE^[9]
12
15
20
20
25
30 ns
t_WC
Write Cycle Time 12
15
20
25
35
45
ns
t_SCE
CE LOW to
9
Write End
10
15
20
30
40
ns
t_AW
Address Set-Up to 9
Write End
10
15
20
30
40
ns
t_HA
Address Hold from 0
0
0
0
0
0
ns
Write End
t_SA
Address Set-Up to 0
0
0
0
0
0
ns
Write Start
t_PWE
t_SD
WE Pulse Width
8
Data Set-Up to
8
Write End
9
15
20
25
30
ns
9
10
15
17
20
ns
t_HD
Data Hold from
0
0
0
0
0
0
ns
Write End
t_LZWE
WE HIGH to
Low Z^[7]
2
2
3
3
3
3
ns
t_HZWE
WE LOW to
High Z^[7,8]
7
7 0 10 0 11 0 15 0 15 ns
Notes:
6. Test conditions assume signal transition time of 3 ns or less for -12 and -15 speeds and 5 ns or less for -20 and slower speeds, timing reference levels of
1.5V, input pulse levels of 0 to 3.0V, and output loading of the specified I_OL/I_OH and 30-pF load capacitance.
7. At any given temperature and voltage condition, t_HZCE is less than t_LZCE and t_HZWE is less than t_LZWE for any given device.
8. t_HZCE and t_HZWE are specified with C_L = 5 pF as in part (b) in AC Test Loads and Waveforms. Transition is measured ±500 mV from steady-state voltage.
9. The internal write time of the memory is defined by the overlap of CE LOW and WE LOW. Both signals must be LOW to initiate a write and either signal can
terminate a write by going HIGH. The data input set-up and hold timing should be referenced to the rising edge of the signal that terminates the write.
Document #: 38-05049 Rev. **
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