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External clock drive waveforms, Atmega161(l) – Rainbow Electronics ATmega161L User Manual

Page 132

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132

ATmega161(L)

1228C–AVR–08/02

If I

OH

exceeds the test condition, V

OH

may exceed the related specification. Pins are not guaranteed to source current

greater than the listed test condition.

5. Minimum V

CC

for power-down is 2V.

External Clock Drive
Waveforms

Figure 82. External Clock

Notes:

1. See “External Data Memory Timing” for a description of how the duty cycle influences

the timing for the external Data memory.

Table 50. External Clock Drive

(1)

Symbol

Parameter

V

CC

= 2.7V to

5.5

V

V

CC

= 4.0V to

5.5

V

Units

Min

Max

Min

Max

1/t

CLCL

Oscillator Frequency

0

4

0

8

MHz

t

CLCL

Clock Period

250

125

ns

t

CHCX

High Time

100

50

ns

t

CLCX

Low Time

100

50

ns

t

CLCH

Rise Time

1.6

0.5

µs

t

CHCL

Fall Time

1.6

0.5

µs

VIL1

VIH1