AT89C51RB2 Atmel Corporation, AT89C51RB2 Datasheet - Page 117

• Manufacturer Part Number: AT89C51RB2
• Manufacturer: Atmel Corporation

Specifications of AT89C51RB2

• Flash (kbytes): 16 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Uart: 1
• Sram (kbytes): 1.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART
• Watchdog: Yes

Shift Register Timing
Waveforms
External Clock Drive
Waveforms
AC Testing Input/Output
Waveforms
Float Waveforms
Clock Waveforms
4180E–8051–10/06
INSTRUCTION
ALE
CLOCK
OUTPUT DATA
WRITE to SBUF
INPUT DATA
CLEAR RI
T
QVXH
0
AC inputs during testing are driven at V
Timing measurement are made at V
For timing purposes as port pin is no longer floating when a 100 mV change from load
voltage occurs and begins to float when a 100 mV change from the loaded V
occurs. I
Valid in normal clock mode. In X2 mode XTAL2 must be changed to XTAL2/2.
T
XHDV
INPUT/OUTPUT
0.45V
1
0
V
VALID
T
CC
XLXL
OL
-0.5V
/I
OH
T
XHQX
2
1
≥ ± 20mA.
VALID
0.2V
0.7V
T
3
CC
XHDX
2
VALID
CC
T
-0.1
V
CHCL
CC
V
V
OH
OL
0.45 V
-0.5V
+ 0.1 V
- 0.1 V
4
3
VALID
IH
min for a logic “1” and V
FLOAT
V
CC
LOAD
5
4
T
VALID
- 0.5 for a logic “1” and 0.45V for a logic “0”.
CLCX
6
5
0.2 V
0.2 V
VALID
AT89C51RB2/RC2
T
CLCL
CC
CC
+ 0.9
- 0.1
V
V
7
6
T
LOAD
LOAD
VALID
CLCH
IL
T
CHCX
max for a logic “0”.
+ 0.1 V
- 0.1 V
SET TI
SET RI
8
7
VALID
OH
/V
OL
level
117