AT90S1200-4SC Atmel, AT90S1200-4SC Datasheet - Page 14

• Manufacturer Part Number: AT90S1200-4SC
• Description: MCU 1K ISP FLASH 4MHZ 20-SOIC
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S1200-4SC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: SPI
• Peripherals: POR, WDT
• Number Of I /o: 15
• Program Memory Size: 1KB (512 x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 6 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 20-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Ram Size: -
• Data Converters: -

External Reset
Watchdog Reset
14
AT90S1200
been applied, the Power-on Reset period can be extended. Refer to Figure 15 for a tim-
ing example on this.
Figure 15. MCU Start-up, RESET Controlled Externally
An External Reset is generated by a low level on the RESET pin. Reset pulses longer
than 50 ns will generate a reset, even if the clock is not running. Shorter pulses are not
guaranteed to generate a reset. When the applied signal reaches the Reset Threshold
Voltage (V
period t
Figure 16. External Reset during Operation
When the Watchdog times out, it will generate a short reset pulse of 1 XTAL cycle dura-
tion. On the falling edge of this pulse, the delay timer starts counting the Time-out period
t
TOUT
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
RESET
RESET
. Refer to page 23 for details on operation of the Watchdog.
VCC
VCC
TOUT
RST
has expired.
) on its positive edge, the delay timer starts the MCU after the Time-out
V
POT
V
RST
t
TOUT
0838H–AVR–03/02