ATmega8(L)

ADC Characteristics

Table 103. ADC Characteristics

Symbol	Parameter	Condition		Min(1)	Typ(1)		Max(1)		Units
	Resolution	Single Ended Conversion			10				Bits
		Single Ended Conversion
	Absolute accuracy	VREF = 4V, VCC = 4V			1.75				LSB
	(Including INL, DNL,	ADC clock = 200 kHz
	Quantization Error, Gain,	Single Ended Conversion
	and Offset Error)
		VREF = 4V, VCC = 4V			3				LSB
		ADC clock = 1 MHz
		Single Ended Conversion
		VREF = 4V, VCC = 4V
	Integral Non-linearity (INL)	ADC clock = 200 kHz			0.75				LSB
		Single Ended Conversion
	Differential Non-linearity	VREF = 4V, VCC = 4V
	(DNL)	ADC clock = 200 kHz			0.5				LSB
	Gain Error	Single Ended Conversion			1				LSB
		VREF = 4V, VCC = 4V
		ADC clock = 200 kHz
	Offset Error	Single Ended Conversion			1				LSB
		VREF = 4V, VCC = 4V
		ADC clock = 200 kHz
	Conversion Time	Free Running Conversion							µs
	Clock Frequency			50			1000		kHz
AVCC	Analog Supply Voltage		V	- 0.3(2)		V	CC	+ 0.3(3)	V
				CC
VREF	Reference Voltage			2.0			AVCC		V
VIN	Input voltage			GND			VREF		V
	Input bandwidth				38.5				kHz
VINT	Internal Voltage Reference			2.3	2.56			2.7	V
RREF	Reference Input Resistance				32				kΩ
RAIN	Analog Input Resistance			55	100				MΩ

Notes: 1. Values are guidelines only.

2.Minimum for AVCC is 2.7V.

3.Maximum for AVCC is 5.5V.

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ATmega8 Typical

Characteristics

Active Supply Current

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 temperature. The dominating factors are operating voltage and frequency.

The current drawn from capacitive loaded pins may be estimated (for one pin) as CL*VCC*f where CL = load capacitance, VCC = 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 current drawn by the Watchdog Timer.

Figure 118. Active Supply Current vs. Frequency (0.1 - 1.0 MHz)

ACTIVE SUPPLY CURRENT vs. FREQUENCY

						0.1 - 1.0 MHz
	3
	2.5										5.5V
											5.0V
											4.5V
	2										4.0V
(mA)											3.3V
	1.5										3.0V
											2.7V
CC
I
	1
	0.5
	0
	0	0.1	0.2	0.3	0.4	0.5	0.6	0.7	0.8	0.9	1

Frequency (MHz)

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ATmega8(L)

Figure 119. Active Supply Current vs. Frequency (1 - 20 MHz)

ACTIVE SUPPLY CURRENT vs. FREQUENCY

						1 - 20 MHz
	30
											5.5V
	25										5.0V
	20										4.5V
(mA)	15
CC
I
	10								3.3V
	5						3.0V
						2.7V
	0
	0	2	4	6	8	10	12	14	16	18	20

Frequency (MHz)

Figure 120. Active Supply Current vs. VCC (Internal RC Oscillator, 8 MHz)

ACTIVE SUPPLY CURRENT vs. VCC

INTERNAL RC OSCILLATOR, 8 MHz

	18
	16
	14						-40°C
							25°C
	12						85°C
(mA)	10
CC	8
I
	6
	4
	2
	0
	2.5	3	3.5	4	4.5	5	5.5

VCC (V)

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Figure 121. Active Supply Current vs. VCC (Internal RC Oscillator, 4 MHz)

ACTIVE SUPPLY CURRENT vs. VCC

INTERNAL RC OSCILLATOR, 4 MHz

	12
	10
							-40°C
	8						25°C
(mA)							85°C
	6
CC
I
	4
	2
	0
	2.5	3	3.5	4	4.5	5	5.5

VCC (V)

Figure 122. Active Supply Current vs. VCC (Internal RC Oscillator, 2 MHz)

ACTIVE SUPPLY CURRENT vs. VCC

INTERNAL RC OSCILLATOR, 2 MHz

	6
							25°C
	5						-40°C
							85°C
	4
(mA)	3
CC
I
	2
	1
	0
	2.5	3	3.5	4	4.5	5	5.5

VCC (V)

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Figure 123. Active Supply Current vs. VCC (Internal RC Oscillator, 1 MHz)

ACTIVE SUPPLY CURRENT vs. VCC

INTERNAL RC OSCILLATOR, 1 MHz

	3.5
	3						25°C	85°C
	2.5						-40°C
(mA)	2
CC	1.5
I
	1
	0.5
	0
	2.5	3	3.5	4	4.5	5		5.5

VCC (V)

Figure 124. Active Supply Current vs. VCC (32 kHz External Oscillator)

ACTIVE SUPPLY CURRENT vs. VCC

32kHz EXTERNAL OSCILLATOR

	120
	100
							25°C
	80
(uA)	60
CC
I
	40
	20
	0
	2.5	3	3.5	4	4.5	5	5.5

VCC (V)

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