Rainbow Electronics ATtiny43U - Manual (Page 165)

165
8048B–AVR–03/09
21. Typical Characteristics – TBD
The data contained in this section is largely based on simulations and characterization of similar
devices in the same process and design methods. Thus, the data should be treated as indica-
tions of how the part will behave.
The following charts show typical behavior. These figures are not tested during manufacturing.
During characterisation devices are operated at frequencies higher than test limits but they are
not guaranteed to function properly at frequencies higher than the ordering code indicates.
All current consumption measurements are performed with all I/O pins configured as inputs and
with internal pull-ups enabled. Current consumption is a function of several factors such as oper-
ating 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.
A sine wave generator with rail-to-rail output is used as clock source but current consumption in
Power-Down mode is independent of clock selection. The difference between current consump-
tion 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.
The current drawn from pins with a capacitive load may be estimated (for one pin) as follows:
where V
CC
= operating voltage, C
L
= load capacitance and f
SW
= average switching frequency of
I/O pin.
21.1 Boost Converter
Figure 21-1. Typical Transition Range Between Active Modes of Operation
I
CP
V
CC
C
L
f
Ч Ч
SW
≈
0
0.8
1.6
2.0
Load Current (mA)
V
BAT
(V)
0.1 0 0.2 0.3
TYPICAL TRANSITION RANGES BETWEEN MODES OF OPERATION
1.2
0.4
0.4 0.5 0.6 0.7
AC
TIV
E L
OW
CU
RR
ENT
MO
DE
ACT
IVE
REG
ULAT
ED M
ODE
ACTIVE REGULATED MODE
ACTIVE LOW CURRENT MODE
STOP MODE