TS87C52X2 ATMEL Corporation, TS87C52X2 Datasheet - Page 41

• Manufacturer Part Number: TS87C52X2
• Description: 8-bit Microcontroller 8 Kbytes Otp
• Manufacturer: ATMEL Corporation

External Program Memory
Characteristics
4184E–8051–09/02
Table 28., Table 31. and Table 34. 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 25. Max frequency for derating formula regarding the speed grade
Example:
T
Table 26. Symbol Description
LLIV
Freq (MHz)
Symbol
T (ns)
T
T
T
T
T
T
T
T
T
T
T
T
in X2 mode for a -V part at 20 MHz (T = 1/20
AVLL
LLAX
PLPH
PXAV
PLAZ
LHLL
LLPL
PXIX
AVIV
x= 22 (Table 28.)
T= 50ns
T
PLIV
PXIZ
LLIV
T
LLIV
= 2T - x = 2 x 50 - 22 = 78ns
Parameter
Oscillator clock period
ALE pulse width
Address Valid to ALE
Address Hold After ALE
ALE to Valid Instruction In
ALE to PSEN
PSEN Pulse Width
PSEN to Valid Instruction In
Input Instruction Hold After PSEN
Input Instruction FloatAfter PSEN
PSEN to Address Valid
Address to Valid Instruction In
PSEN Low to Address Float
-M X1 mode
40
25
-M X2 mode
20
50
-V X1 mode
40
25
E6
-V X2 mode
= 50 ns):
33.3
30
-L X1 mode
TS8xCx2X2
33.3
30
-L X2 mode
20
50
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