AT90S/LS4434 and AT90S/LS8535
100
Typical Characteristics
The following charts show typical behavior. These figures are not tested during manufacturing. All current consumption
measurements are performed with all I/O pins configured as inputs and with internal pull-ups enabled. A sine wave genera-
tor with rail-to-rail output is used as clock source.
The power consumption in Power-down Mode is independent of clock selection.
The current consumption is a function of several factors such as: operating voltage, operating frequency, loading of I/O
pins, switching rate of I/O pins, code executed and ambient temperature. The dominating factors are operating voltage and
frequency.
The current drawn from capacitive loaded pins may be estimated (for one pin) as C
L
•V
CC
•f where C
L
= load capacitance,
V
CC
= operating voltage and f = average switching frequency of I/O pin.
The parts are characterized at frequencies higher than test limits. Parts are not guaranteed to function properly at frequen-
cies higher than the ordering code indicates.
The difference between current consumption in Power-down Mode with Watchdog Timer enabled and Power-down Mode
with Watchdog Timer disabled represents the differential current drawn by the Watchdog Timer.
Figure 75.
Active Supply Current vs. Frequency
ACTIVE SUPPLY CURRENT vs. FREQUENCY
T = 25˚C
A
Frequency (MHz)
I
cc
(mA)
V
cc
= 5.5V
V
cc
= 5V
0
5
10
15
20
25
30
35
40
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
V
cc
= 2.7V
V
cc
= 3.0V
V
cc
= 3.3V
V
cc
= 3.6V
V
cc
= 4V
V
cc
= 4.5V
V
cc
= 6V
