AT90PWM81 Atmel Corporation, AT90PWM81 Datasheet - Page 52

• Manufacturer Part Number: AT90PWM81
• Manufacturer: Atmel Corporation

Specifications of AT90PWM81

• Flash (kbytes): 8 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 20
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 125
• Analog Comparators: 3
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.25
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 1
• Output Compare Channels: 8
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

7.1.5
52
AT90PWM81
Brown-out Detection
AT90PWM81 has an On-chip Brown-out Detection (BOD) circuit for monitoring the V
operation by comparing it to a fixed trigger level. The trigger level for the BOD can be selected by the
BODLEVEL Fuses. The trigger level has a hysteresis to ensure spike free Brown-out Detection. The hys-
teresis on the detection level should be interpreted as V
V
Table 7-2.
Notes:
Table 7-3.
Notes:
When V
immediately activated. When V
ter starts the MCU after the Time-out period t
The BOD circuit will only detect a drop in V
t
BOD
Symbol
V
t
HYST
BOD
HYST
given in
/2.
BODLEVEL 2..0 Fuses
CC
1. V
2. Values are guidelines only.
1. Values are guidelines only.
( default configuration)
decreases to a value below the trigger level (V
case, the device is tested down to V
Out Reset will occur before V
longer guaranteed. The test is performed using BODLEVEL = 010 for Low Operating Voltageand
BODLEVEL = 101for High Operating Voltage.
Table
BOT
BODLEVEL Fuse Coding
Brown-out Characteristics
Parameter
Brown-out Detector Hysteresis
Min Pulse Width on Brown-out Reset
may be below nominal minimum operating voltage for some devices. For devices where this is the
110
101
100
011
010
001
000
111
7-3.
CC
increases above the trigger level (V
CC
drops to a voltage where correct operation of the microcontroller is no
(1)
(1)(2)
Min V
CC
CC
TOUT
3.9
2.5
= V
if the voltage stays below the trigger level for longer than
BOT
BOT
has expired.
during the production test. This guarantees that a Brown-
Forbidden, BOD must be enabled
BOT+
BOT-
Typ V
Min.
= V
4.5
2.7
4.3
4.4
4.2
2.8
2.7
in
BOT
Figure
BOT
BOT+
+ V
Typ.
in
70
7-5), the Brown-out Reset is
2
HYST
Figure
Max V
/2 and V
4.6
2.9
7-5), the delay coun-
Max.
BOT
CC
7734P–AVR–08/10
BOT-
level during
= V
Units
Units
mV
V
V
V
V
V
V
V
µs
BOT
-