atmega161-4pi ATMEL Corporation, atmega161-4pi Datasheet - Page 135

• Manufacturer Part Number: atmega161-4pi
• Description: 8-bit Microcontroller With 16k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Table 55. External Data Memory Characteristics, 2.7 - 5.5 Volts, No Wait State (Continued)
Notes:
Table 56. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 0, SRWn0 = 1
Table 57. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 1, SRWn0 = 0
Table 58. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 1, SRWn0 = 1
1228D–AVR–02/07
12
13
14
15
16
0
10
12
15
16
0
10
12
15
16
0
10
12
14
15
16
Symbol
t
t
t
t
t
Symbol
1/t
t
t
t
t
Symbol
1/t
t
t
t
t
Symbol
1/t
t
t
t
t
t
RLRH
DVWL
WHDX
DVWH
WLWH
RLDV
RLRH
DVWH
WLWH
RLDV
RLRH
DVWH
WLWH
RLDV
RLRH
WHDX
DVWH
WLWH
1. This assumes 50% clock duty cycle. The half period is actually the high time of the external clock, XTAL1.
2. This assumes 50% clock duty cycle. The half period is actually the low time of the external clock, XTAL1.
CLCL
CLCL
CLCL
Parameter
RD Pulse Width
Data Setup to WR Low
Data Hold After WR High
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Hold After WR High
Data Valid to WR High
WR Pulse Width
Min
230
125
210
230
Min
480
460
480
Min
730
710
730
Min
730
375
710
730
70
4 MHz Oscillator
4 MHz Oscillator
4 MHz Oscillator
4 MHz Oscillator
Max
Max
Max
Max
335
585
585
1.0t
0.5t
1.0t
1.0t
2.0t
2.0t
2.0t
3.0t
3.0t
3.0t
3.0t
3.0t
3.0t
0.5t
1.5t
Min
Min
Min
Min
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
0.0
0.0
0.0
CLCL
CLCL
Variable Oscillator
Variable Oscillator
Variable Oscillator
Variable Oscillator
-20
-55
-40
-20
-20
-40
-20
-20
-40
-20
-20
-40
-20
-0
-0
ATmega161(L)
2.0t
3.0t
3.0t
CLCL
CLCL
CLCL
Max
Max
Max
Max
4.0
4.0
4.0
-165
-165
-165
MHz
MHz
MHz
Unit
ns
ns
ns
ns
ns
Unit
ns
ns
ns
ns
Unit
ns
ns
ns
ns
Unit
ns
ns
ns
ns
ns
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