AT89LP828 Atmel Corporation, AT89LP828 Datasheet - Page 24

• Manufacturer Part Number: AT89LP828
• Manufacturer: Atmel Corporation

Specifications of AT89LP828

• Flash (kbytes): 8 Kbytes
• Max. Operating Frequency: 25 MHz
• Cpu: 8051-1C
• Max I/o Pins: 30
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.75
• Eeprom (bytes): 1024
• Self Program Memory: IAP
• Operating Voltage (vcc): 2.4 to 5.5
• Timers: 3
• Isp: SPI/OCD
• Watchdog: Yes

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AT89LP428/828
Figure 7-1.
Note:
If the Brown-out Detector (BOD) is also enabled, the start-up timer does not begin counting until
after V
occurs prior to the end of the initialization sequence, the timer must first wait for that sequence to
complete before counting.
The start-up timer delay is user-configurable with the Start-up Time User Fuses and depends on
the clock source
after a Brown-out Reset or when waking up from Power-down during internally timed mode. The
start-up delay should be selected to provide enough settling time for V
source. The device operating environment (supply voltage, frequency, temperature, etc.) must
meet the minimum system requirements before the device exits reset and starts normal opera-
tion. The RST pin may be held low externally until these conditions are met.
Figure 7-2.
Time-out
Time-out
Internal
Internal
Internal
Internal
CC
Reset
Reset
Reset
Reset
RST
RST
t
V
POR
RST
RST
reaches the BOD threshold voltage V
V
CC
CC
is approximately 92 µs ± 5%.
Power-on Reset Sequence (BOD Disabled)
Power-on Reset Sequence (BOD Enabled)
t
POR
(Table
V
POR
7-1). The Start-up Time fuses also control the length of the start-up time
(RST Controlled Externally)
(RST Controlled Externally)
V
V
BOD
POR
t
POR
+ t
SUT
t
SUT
BOD
(RST Tied to V
(RST Tied to V
as shown in
t
RHD
CC
Figure
V
CC
)
V
IH
IH
)
V
POR
t
RHD
7-2. However, if this event
CC
and the selected clock
3654A–MICRO–8/09