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Typical characteristics, 1 supply current of i/o modules – Rainbow Electronics ATtiny10 User Manual

Page 122

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122

8127B–AVR–08/09

ATtiny4/5/9/10

17. Typical Characteristics

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.

17.1

Supply Current of I/O Modules

Tables and formulas below can be used to calculate additional current consumption for the dif-
ferent I/O modules in Active and Idle mode. Enabling and disabling of I/O modules is controlled
by the Power Reduction Register. See

“Power Reduction Register” on page 24

for details.

Note:

1. The ADC is available in ATtiny5/10, only

Table 17-2

below can be used for calculating typical current consumption for other supply volt-

ages and frequencies than those mentioned in the

Table 17-1

above.

Note:

1. The ADC is available in ATtiny5/10, only

I

CP

V

CC

C

L

f

Ч

Ч

SW

Table 17-1.

Additional Current Consumption for the different I/O modules (absolute values)

PRR bit

Typical numbers

V

CC

= 2V, f = 1MHz

V

CC

= 3V, f = 4MHz

V

CC

= 5V, f = 8MHz

PRTIM0

6.6 uA

40.0 uA

153.0 uA

PRADC

(1)

29.6 uA

88.3 uA

333.3 uA

Table 17-2.

Additional Current Consumption (percentage) in Active and Idle mode

PRR bit

Current consumption additional to
active mode with external clock
(see

Figure 17-1

and

Figure 17-2

)

Current consumption additional to
idle mode with external clock
(see

Figure 17-7

and

Figure 17-8

)

PRTIM0

2.3 %

10.4 %

PRADC

(1)

6.7 %

28.8 %