Table 12-18.
Refresh----Output Responses (continued)
16MHz
20MHz
Symbol
Parameters
Min.
Max.
Min.
Max.
t269
LOMEGCS delay from -REFRESH
----
44
----
44
t270
-CAS fall from HLDA rise in CAS-RAS HLDA
refresh
*
----
*
----
t271
-REFRESH active from PROCCLK in Hidden
Refresh, or in HLDA refresh in Early READY mode
following memory write
----
50
----
50
t272
-XMEMR fall from PROCCLK in Hidden Refresh
----
50
----
50
t273
-XMEMR rise from PROCCLK in Hidden Refresh
----
50
----
50
*
Not applicable to 82C836B. 10ns minimum for 82C836A.
Table 12-19.
Refresh----Formula Specifications
16MHz
20MHz
Symbol
Critical Path
Formula
Min.
Max.
Min.
Max.
te260
REF to XMEMR delay in HLDA
refresh
t260-t263
----
16
----
16
te270
CAS precharge in CAS-RAS refresh
t270-t103
*
----
*
----
te271
REF to XMEMR in Early READY
mode
t271-t263
----
16
----
16
te271a
REF to XMEMR delay in Hidden
Refresh
t271-t272
----
5**
----
5**
te272
XMEMR low time in Hidden Refresh
t272-t273
----
15***
----
15***
te273
Address hold after XMEMR rise
t273-t271
----
50
----
38
*
** 1ns maximum for 82C836A.
*** 4ns maximum for 836A.
Not applicable to 82C836B. 9ns minimum for 82C836A.
Table 12-20.
Refresh----Input Requirements
16MHz
20MHz
Symbol
Parameters
Min.
Max.
Min.
Max.
t280
IOCHRDY setup before OSC2 rise
IOCHRDY hold after OSC2 rise
-REFRESH setup before OSC2 rise
20
----
15
----
t281
7
----
5
----
t282
25
----
20
----
Certain input parameters, as noted, are nonrestrictive. If these parameters are violated, the signa
until the subsequent clocking period. The parameter specifies only the conditions needed to guarant
signal on a particular clock edge.
l may not be recognized
ee recognition of the
System Characteristics
AC Characteristics 16- and 20MHz
I
Chips and Technologies, Inc.
P R E L I M I N A R Y
Revision 3.0
12-11