C541U Datasheet, PDF (47/63 Pages) Siemens Semiconductor Group – 8 BIT CMOS MICROCONTROLLER

C541U
AC Characteristics
(Operating Conditions apply)
(C_L for port 0, ALE and PSEN outputs = 100 pF; C_L for all other outputs = 80 pF)
Program Memory Characteristics
Parameter
ALE pulse width
Address setup 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 float after PSEN
Address valid after PSEN
Address to valid instruction in
Address float to PSEN
Symbol
Limit Values
Unit
10-MHz clock
Duty Cycle
0.4 to 0.6
Variable Clock
1/CLP = 2 MHz to
12 MHz **)
min. max. min.
max.
t_LHLL
43
t_AVLL
13
t_LLAX
13
t_LLIV
–
t_LLPL
13
t_PLPH
86
t_PLIV
–
t_PXIX
0
t *)
PXIZ
–
t *)
PXAV
28
t_AVIV
–
t_AZPL
0
–
CLP - 40 –
ns
–
TCL_Hmin -20 –
ns
–
TCL_Hmin -20 –
ns
80 –
2 CLP - 87 ns
–
TCL_Lmin -20 –
ns
–
CLP+
–
ns
TCL_Hmin -30
51 –
CLP+
ns
TCL_Hmin- 65
–
0
–
ns
23 –
TCL_Lmin -10 ns
–
TCL_Lmin - 5 –
ns
140 –
2 CLP + ns
TCL_Hmin -60
0
–
ns
*) _{Interfacing the C541U to devices with float times up to 28 ns is permissible. This limited bus contention will not}
cause any damage to port 0 drivers.
**) _{For correct function of the USB module the C541U must operate with 12 MHz external clock. The}
microcontroller (except the USB module) operates down to 2 MHz.
Semiconductor Group
45