SMJ44C251B Datasheet, PDF (18/57 Pages) Texas Instruments – 262144 BY 4-BIT MULTIPORT VIDEO RAM

Austin Semiconductor, Inc.
VRAM
SMJ44C251B
MT42C4256
CAPACITANCE OVER RECOMMENDED RANGES OF SUPPLY
VOLTAGES AND OPERATING FREE-AIR TEMPERATURE, f = 1MHz¹
PARAMETER
Input capacitance, A0 - A8
Input capacitance, CAS\ and RAS\
Output capacitance, SDQs and DQs
Output capacitance, SQSF
SYM
C_i(A)
C_i(RC)
C_o(O)
C_o(QSF)
MIN
MAX
7
7
9
9
UNIT
pF
pF
pF
pF
SWITCHING CHARACTERISTICS OVER RECOMMENDED RANGES
OF SUPPLY VOLTAGES AND OPERATING FREE-AIR TEMPERA-
TURE²
PARAMETER
SYM/ALT. SYM CONDITIONS⁴
-10
MIN MAX
-12
MIN MAX UNIT
Access time from CAS\
t_a(C)/t_CAC
t_d(RLCL) = MAX
25
30 ns
Access time from column address
t_a(CA)/t_CAA
t_d(RLCL) = MAX
50
60 ns
Access time from CAS\ high
t_a(CP) /t_CPA
t_d(RLCL) = MAX
55
65 ns
Access time from RAS\
t_a(R)/t_RAC
t_d(RLCL) = MAX
100
120 ns
Access time of DQ0 - DQ3 from TRG\ low
t_a(G)/t_OEA
25
30 ns
Access time of SDQ0 - SDQ3 from SC high
t_a(SQ)/t_SCA
C_L = 30pF
30
35 ns
Access time of SDQ0 - SDQ3 from SE\ low
t_a(SE) /t_SEA
C_L = 30pF
20
25 ns
Disable time, random output from CAS\ high³
Disable time, random output from TRG\ high³
Disable time, random output from SE\ high³
t_dis(CH)/t_OFF
t_dis(G) /t_OEZ
t_dis(SE) /t_SEZ
C_L = 100pF
C_L = 100pF
C_L = 30pF
0
20
0
20 ns
0
20
0
20 ns
0
20
0
20 ns
NOTES:
1. Capacitance is sampled only at initial design and after any major change. Samples are tested at 0 V and 25°C with a 1-MHz signal applied to the
terminal under test. All other terminals are open.
2. Switching times assume C_L = 100 pF unless otherwise noted (see Figure 12).
3. t_dis(CH), t_dis(G), and t_dis(SE) are specified when the output is no longer driven.
4. For conditions shown as MIN/ MAX, use the appropriate value specified in the timing requirements.
SMJ44C251B/MT42C4256
Rev. 0.1 12/03
18
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.