AT89C4051 Atmel Corporation, AT89C4051 Datasheet - Page 14

• Manufacturer Part Number: AT89C4051
• Manufacturer: Atmel Corporation

Specifications of AT89C4051

• Flash (kbytes): 4 Kbytes
• Max. Operating Frequency: 24 MHz
• Cpu: 8051-12C
• Max I/o Pins: 15
• Uart: 1
• Sram (kbytes): 0.125
• Operating Voltage (vcc): 2.7 to 6.0
• Timers: 2

20. Serial Port Timing: Shift Register Mode Test Conditions
V
21. Shift Register Mode Timing Waveforms
22. AC Testing Input/Output Waveforms
Note:
23. Float Waveforms
Note:
14
Symbol
t
t
t
t
t
CC
XLXL
QVXH
XHQX
XHDX
XHDV
= 5.0V ± 20%; Load Capacitance = 80 pF
1. AC Inputs during testing are driven at V
1. For timing purposes, a port pin is no longer floating when a 100 mV change from load voltage occurs. A port pin begins to
AT89C4051
min. for a logic 1 and V
float when 100 mV change from the loaded V
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
(1)
IL
max. for a logic 0.
CC
- 0.5V for a logic 1 and 0.45V for a logic 0. Timing measurements are made at V
OH
/V
OL
level occurs.
(1)
Min
700
1.0
50
0
12 MHz Osc
Max
700
10t
2t
12t
CLCL
CLCL
Min
Variable Oscillator
0
CLCL
-117
-133
10t
CLCL
Max
-133
1001F–MICRO–6/08
Units
µs
ns
ns
ns
ns
IH