AT80C51RA2-RLSIV datasheet(63/86 Pages) ATMEL

63 / 86 page

4188F–8051–01/08

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

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

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

-M

-V

-L

Port 0

100

Port 1, 2, 3

ALE / PSEN

100

-M X1 mode

-M X2 mode

-V X1 mode

-V X2 mode

-L X1 mode

-L X2 mode

Freq (MHz)

T (ns)

33.3

AT80C51RA2-RLSIV Datasheet(PDF) 63 Page - ATMEL Corporation