AT89LP428 Atmel Corporation, AT89LP428 Datasheet - Page 123

• Manufacturer Part Number: AT89LP428
• Manufacturer: Atmel Corporation

Specifications of AT89LP428

• Flash (kbytes): 4 Kbytes
• Max. Operating Frequency: 25 MHz
• Cpu: 8051-1C
• Max I/o Pins: 30
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.75
• Eeprom (bytes): 512
• Self Program Memory: IAP
• Operating Voltage (vcc): 2.4 to 5.5
• Timers: 3
• Isp: SPI/OCD
• Watchdog: Yes

23.9.2
3654A–MICRO–8/09
Power-down Sequence
Figure 23-5. Serial Programming Power-up Sequence
Execute this sequence to power-down the device after programming.
Figure 23-6. Serial Programming Power-down Sequence
1. Drive SCK low.
2. Wait at least t
3. Tristate MOSI.
4. Wait at least t
5. Wait no more than t
MISO
MOSI
MISO
MOSI
SCK
RST
V
RST
SCK
V
SS
CC
SS
CC
t
SSD
SSD
SSZ
and then tristate SS and SCK.
and bring SS high.
PWRDN
t
PWRUP
and power off V
t
SSZ
HIGH Z
HIGH Z
HIGH Z
HIGH Z
t
POR
+ t
cc
.
SUT
t
PWRDN
t
ZSS
AT89LP428/828
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