Released
Datasheet
PM73487 QRT
PMC-Sierra, Inc.
PMC-980618
Issue 3
622 Mbps ATM Traffic Management Device
Symbol
Parameter
Signals
ALRAM_CLK
Min
Max
Units
Tcyc
Tch
Clock period
10
3
ns
ns
ns
ns
Clock high period
Clock low period
Address setup time
ALRAM_CLK
ALRAM_CLK
Tcl
3
Tadrsu
ALRAM_ADD(18:0),
ALRAMADD17N,
ALRAMADD18N
2.7
Tadrh
Address hold time
ALRAM_ADD(18:0),
ALRAMADD17N,
ALRAMADD18N
1.5
ns
Toesu
Toeh
Tadss
Tadh
Trds
Output enable setup time
/ALRAM_OE
3.5
-1
ns
ns
ns
ns
ns
ns
ns
ns
Output enable hold time
/ALRAM_OE
Address strobe setup time
Address strobe hold time
/ALRAM_ADSC
/ALRAM_ADSC
ALRAM_DATA(16:0)
ALRAM_DATA(16:0)
/ALRAM_WE
2.8
1.5
3.8
1.5
2.9
1.2
(Read) Data valid required before clock
(Read) Data valid required after clock
Write enable setup time
Trdh
Twesu
Tweh
Write enable hold time
/ALRAM_WE
Figure 57 shows the AL RAM write timing.
ALRAM WRITE CYCLE
1
2
3
4
5
Tcyc
Tch
Tcl
ALRAM_CLK
ALRAM_ADSC
Tadh
Toeh
Tadrh
Tadrh
Tadrh
Tweh
Tdh
Tadss
Toesu
Tadrsu
Tadrsu
Tadrsu
/ALRAM_OE
ALRAM_ADD(18:0)
ALRAMADD17N
ALRAMADD18N
Twesu
Tds
ALRAM_WE
ALRAM_DATA(16:0)
VALID DATA
Figure 57. Address Lookup RAM Write Timing
84
PMC [ PMC-SIERRA, INC ]
