External clock drive waveforms, External clock drive, Atmega32(l) – Rainbow Electronics ATmega32L User Manual
Page 286
286
ATmega32(L)
2503C–AVR–10/02
6] The sum of all IOH, for ports C0 - C7, should not exceed 200 mA.If IOH exceeds the test condition, VOH 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 2.5V.
External Clock Drive
Waveforms
Figure 144. External Clock Drive Waveforms
External Clock Drive
Notes:
1. R should be in the range 3 k
Ω - 100 kΩ, and C should be at least 20 pF. The C values
given in the table includes pin capacitance. This will vary with package type.
2. The frequency will vary with package type and board layout.
V
IL1
V
IH1
Table 118. External Clock Drive
Symbol
Parameter
V
CC
= 2.7V to
5.5
V
V
CC
= 4.5V to
5.5
V
Units
Min
Max
Min
Max
1/t
CLCL
Oscillator Frequency
0
8
0
16
MHz
t
CLCL
Clock Period
125
62.5
ns
t
CHCX
High Time
50
25
ns
t
CLCX
Low Time
50
25
ns
t
CLCH
Rise Time
1.6
0.5
µs
t
CHCL
Fall Time
1.6
0.5
µs
∆
t
CLCL
Change in period from
one clock cycle to the
next
2
2
%
Table 119. External RC Oscillator, Typical Frequencies (V
CC
= 5V)
R [k
Ω]
(1)
C [pF]
f
(2)
100
47
87 kHz
33
22
650 kHz
10
22
2.0 MHz