at89c4051-12sa ATMEL Corporation, at89c4051-12sa Datasheet - Page 12

• Manufacturer Part Number: at89c4051-12sa
• Description: 8-bit Microcontroller With 4k Bytes Flash
• Manufacturer: ATMEL Corporation

Serial Port Timing: Shift Register Mode Test Conditions
(V
Shift Register Mode Timing Waveforms
AC Testing Input/Output Waveforms
Note:
Symbol
t
t
t
t
t
XLXL
QVXH
XHQX
XHDX
XHDV
CC
= 5.0V
1.
AC Inputs during testing are driven at V
a logic 1 and 0.45V for a logic 0. Timing measure-
ments are made at V
max. for a logic 0.
Parameter
Serial Port Clock Cycle Time
Output Data Setup to Clock Rising Edge
Output Data Hold After Clock Rising Edge
Input Data Hold After Clock Rising Edge
Clock Rising Edge to Input Data Valid
20%; Load Capacitance = 80 pF)
IH
min. for a logic 1 and V
CC
- 0.5V for
(1)
IL
Min
700
1.0
50
Float Waveforms
Note:
0
12 MHz Osc
1.
Max
700
For timing purposes, a port pin is no longer float-
ing when a 100 mV change from load voltage
occurs. A port pin begins to float when 100 mV
change frothe loaded V
10t
2t
12t
CLCL
CLCL
Min
Variable Oscillator
(1)
CLCL
0
-117
-133
OH
10t
/V
OL
CLCL
Max
level occurs.
-133
Units
ns
ns
ns
ns
s
12