AT89LS51 Atmel Corporation, AT89LS51 Datasheet - Page 23

• Manufacturer Part Number: AT89LS51
• Manufacturer: Atmel Corporation

Specifications of AT89LS51

• Flash (kbytes): 4 Kbytes
• Max. Operating Frequency: 16 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Uart: 1
• Sram (kbytes): 0.125
• Operating Voltage (vcc): 2.7 to 4.0
• Timers: 2
• Isp: SPI
• Watchdog: Yes

23. AC Characteristics
Under operating conditions, load capacitance for Port 0, ALE/PROG, and PSEN = 100 pF; load capacitance for all other
outputs = 80 pF.
23.1
3053C–MICRO–6/08
Symbol
1/t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
LHLL
AVLL
LLAX
LLIV
LLPL
PLPH
PLIV
PXIX
PXIZ
PXAV
AVIV
PLAZ
RLRH
WLWH
RLDV
RHDX
RHDZ
LLDV
AVDV
LLWL
AVWL
QVWX
QVWH
WHQX
RLAZ
WHLH
CLCL
External Program and Data Memory Characteristics
Parameter
Oscillator Frequency
ALE Pulse Width
Address Valid to ALE Low
Address Hold After ALE Low
ALE Low to Valid Instruction In
ALE Low to PSEN Low
PSEN Pulse Width
PSEN Low to Valid Instruction In
Input Instruction Hold After PSEN
Input Instruction Float After PSEN
PSEN to Address Valid
Address to Valid Instruction In
PSEN Low to Address Float
RD Pulse Width
WR Pulse Width
RD Low to Valid Data In
Data Hold After RD
Data Float After RD
ALE Low to Valid Data In
Address to Valid Data In
ALE Low to RD or WR Low
Address to RD or WR Low
Data Valid to WR Transition
Data Valid to WR High
Data Hold After WR
RD Low to Address Float
RD or WR High to ALE High
Min
142
275
275
137
122
287
16 MHz Oscillator
85
22
32
32
75
13
13
23
0
0
Max
150
207
147
350
397
239
103
82
37
10
65
0
6t
6t
4t
7t
2t
3t
3t
t
t
t
t
t
t
CLCL
CLCL
CLCL
t
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
Min
Variable Oscillator
0
0
0
-40
-30
-30
-100
-100
-130
-50
-150
-50
-40
-40
-45
-8
-50
4t
3t
5t
5t
8t
9t
3t
2t
t
t
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
Max
16
10
AT89LS51
0
+40
-100
-105
-25
-105
-165
-150
-165
+50
-60
Units
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
23