Datasheet

Table 30-4. External RC Oscillator, Typical Frequencies
R [kΩ]
(1)
C [pF] f
(2)
33 22 650kHz
10 22 2.0MHz
Note:
1. R should be in the range 3kΩ - 100kΩ, and C should be at least 20pF. The C values given in the
table includes pin capacitance. This will vary with package type.
2. The frequency will vary with package type and board layout.
30.4. System and Reset Characteristics
Table 30-5. Reset, Brown-out and Internal Voltage Reference Characteristics
Symbol Parameter Condition Min Typ Max Units
V
POT
Power-on Reset Threshold Voltage (rising)
(1)
1.4 2.3 V
Power-on Reset Threshold Voltage (falling) 1.3 2.3 V
V
RST
RESET Pin Threshold Voltage 0.2 0.9 V
CC
t
RST
Minimum pulse width on RESET Pin 1.5 μs
V
BOT
Brown-out Reset Threshold Voltage
(2)
BODLEVEL = 1 2.5 2.7 2.9 V
BODLEVEL = 0 3.6 4.0 4.2
t
BOD
Minimum low voltage period for Brown-out Detection BODLEVEL = 1 2 μs
BODLEVEL = 0 2 μs
V
HYST
Brown-out Detector hysteresis 50 mV
V
BG
Bandgap reference voltage 1.15 1.23 1.35 V
t
BG
Bandgap reference start-up time 40 70 μs
I
BG
Bandgap reference current consumption 10 μs
Note:
1. The Power-on Reset will not work unless the supply voltage has been below V
POT
(falling).
2. V
BOT
may be below nominal minimum operating voltage for some devices. For devices where this
is the case, the device is tested down to V
CC
= V
BOT
during the production test. This guarantees
that a Brown-out Reset will occur before V
CC
drops to a voltage where correct operation of the
microcontroller is no longer guaranteed. The test is performed using BODLEVEL = 1 and
BODLEVEL = 0 for ATmega32A.
30.5. Two-wire Serial Interface Characteristics
The table below describes the requirements for devices connected to the Two-wire Serial Bus. The
ATmega32A Two-wire Serial Interface meets or exceeds these requirements under the noted conditions.
Timing symbols refer to Figure 30-3.
Atmel ATmega32A [DATASHEET]
Atmel-8155I-ATmega32A_Datasheet_Complete-08/2016
363