AT80C51RA2-3CSCV View Datasheet(PDF) - International Rectifier
Part Name
Description
MFG CO.
'AT80C51RA2-3CSCV' PDF : 85 Pages View PDF
AT/TS8xC51Rx2
TA = 0 to +70°C (commercial temperature range); VSS = 0 V; 2.7 V < VCC < 5.5 V; -L range.
TA = -40°C to +85°C (industrial temperature range); VSS = 0 V; 2.7 V < VCC < 5.5 V; -L range.
Table 11-3. gives the maximum applicable load capacitance for Port 0, Port 1, 2 and 3, and ALE
and PSEN signals. Timings will be guaranteed if these capacitances are respected. Higher
capacitance values can be used, but timings will then be degraded.
Table 11-3. Load Capacitance versus speed range, in pF
-M
-V
-L
Port 0
100
50
100
Port 1, 2, 3
80
50
80
ALE / PSEN
100
30
100
Table 11-5., Table 39. and Table 42. give the description of each AC symbols.
Table 11-6., Table 11-8. and Table 11-10. give for each range the AC parameter.
Table 11-7., Table 11-9. and Table 11-11. give the frequency derating formula of the AC param-
eter. To calculate each AC symbols, take the x value corresponding to the speed grade you
need (-M, -V or -L) and replace this value in the formula. Values of the frequency must be limited
to the corresponding speed grade:
Table 11-4. Max frequency for derating formula regarding the speed grade
-M X1 mode -M X2 mode -V X1 mode -V X2 mode -L X1 mode -L X2 mode
Freq (MHz)
40
20
40
30
30
20
T (ns)
25
50
25
33.3
33.3
50
Example:
TLLIV in X2 mode for a -V part at 20 MHz (T = 1/20E6 = 50 ns):
x= 22 (Table 11-7.)
T= 50ns
TLLIV= 2T - x = 2 x 50 - 22 = 78ns
63
4188E–8051–08/06
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