AT90USB647-MU Atmel, AT90USB647-MU Datasheet - Page 59

• Manufacturer Part Number: AT90USB647-MU
• Description: MCU, 8BIT, 64K FLASH, USB, 64QFN
• Manufacturer: Atmel

Specifications of AT90USB647-MU

• Controller Family/series: AT90
• No. Of I/o's: 48
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 16MHz
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 64KB
• Oscillator Type: External, Internal
• Package: 64QFN EP
• Device Core: AVR
• Family Name: AT90
• Maximum Speed: 20 MHz
• Ram Size: 4 KB
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 48
• Interface Type: SPI/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 4
• Lead Free Status / Rohs Status: Details

8.4
7593K–AVR–11/09
External Reset
voltage invokes the delay counter, which determines how long the device is kept in RESET after
V
the detection level.
Figure 8-2.
Figure 8-3.
Note:
An External Reset is generated by a low level on the RESET pin. Reset pulses longer than the
minimum pulse width (see
Shorter pulses are not guaranteed to generate a reset. When the applied signal reaches the
Reset Threshold Voltage – V
the Time-out period – t
CC
rise. The RESET signal is activated again, without any delay, when V
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
If V
RESET
RESET
V
V
CC
CC
POR
MCU Start-up, RESET Tied to V
MCU Start-up, RESET Extended Externally
or V
V
V
CCRR
POR
POR
TOUT
parameter range can not be followed, an External Reset is required.
– has expired.
V
V
V
Table
POT
POT
RST
RST
t
– on its positive edge, the delay counter starts the MCU after
TOUT
8-1) will generate a reset, even if the clock is not running.
CC
V
RST
t
TOUT
AT90USB64/128
CC
decreases below
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