Datasheet

187
7701F–AVR–10/12
Atmel ATtiny24/44/84 [Preliminary]
23. Typical Characteristics – Preliminary Data
The data contained in this section is largely based on simulations and characterization of sim-
ilar devices in the same process and design methods. Thus, the data should be treated as
indications of how the part will behave.
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 generator 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 tempera-
ture. 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 frequencies 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 cur-
rent drawn by the Watchdog Timer.
23.1 Active Supply Current
Figure 23-1. Active Supply Current vs. Low Frequency (0.1 - 1.0MHz) - Temp.=25°C
ACTIVE S UP P LY CURRE NT vs . LOW FRE QUE NCY
0.1 - 1.0 MHz - Temperature = 25˚C
5.5 V
5.0 V
4.5 V
3.3 V
3.0 V
2.7 V
0
0.2
0.4
0.6
0.8
1
1.2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
Frequency (MHz)
I
CC
(mA)