ST7LITE49K2 STMicroelectronics, ST7LITE49K2 Datasheet - Page 44

• Manufacturer Part Number: ST7LITE49K2
• Description: 8-bit MCU
• Manufacturer: STMicroelectronics

Specifications of ST7LITE49K2

• 8 Kbytes Single Voltage Extended Flash (xflash) Program Memory With Read-out Protection In-circuit Programming And In-application Programming (icp And Iap) Endurance: 10K write/erase cycles guaranteed Data retention
• 256 Bytes Data Eeprom With Read-out Protection. 300k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55 °C.
• Clock Sources: Internal trimmable 8 MHz RC oscillator, auto-wakeup internal low power - low frequency oscillator, crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-halt, Auto-wakeup from Halt, Wait and Slow

Supply, reset and clock management
Caution:
44/245
When the ST7 is unprogrammed or fully erased, the Flash is blank and the Reset vector is
not programmed. For this reason, it is recommended to keep the RESET pin in low state
until programming mode is entered, in order to avoid unwanted behavior.
The 256 CPU clock cycle delay allows the oscillator to stabilize and ensures that recovery
has taken place from the Reset state. The shorter or longer clock cycle delay is
automatically selected depending on the clock source chosen by option byte.
The Reset vector fetch phase duration is 2 clock cycles.
Table 7.
Figure 14. Reset sequence phases
External Crystal/Ceramic Oscillator (connected to OSC1/OSC2 pins)
External Crystal/Ceramic 1-16 MHz Oscillator
External clock (connected to CLKIN/PB1 pin)
External Crystal/Ceramic 32 kHz Oscillator
CPU clock delay during Reset sequence
Internal RC 32 kHz Oscillator
Internal RC 8 MHz Oscillator
active phase
Clock source
256 or 4096 clock cycles
RESET
Internal reset
vector
Fetch
CPU clock cycle delay
4096
4096
4096
4096
256
256
ST7LITE49K2