ST7LIT10BF1 STMicroelectronics, ST7LIT10BF1 Datasheet - Page 31

• Manufacturer Part Number: ST7LIT10BF1
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, 5 TIMERS, SPI
• Manufacturer: STMicroelectronics

Specifications of ST7LIT10BF1

• Up To 4 Kbytes Single Voltage Extended Flash (xflash) Program Memory With Read-out Protection, In-circuit Programming And In-application Programming (icp And Iap). 10k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55˚C.
• 128 Bytes Data Eeprom With Read-out Protection. 300k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55˚C.
• Clock Sources: Internal 1% RC oscillator (on ST7FLITE15B and ST7FLITE19B), crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-Halt, Auto Wake-up from Halt, Wait and Slow

7.6 SYSTEM INTEGRITY MANAGEMENT (SI)
The System Integrity Management block contains
the Low voltage Detector (LVD) and Auxiliary Volt-
age Detector (AVD) functions. It is managed by
the SICSR register.
Note: A reset can also be triggered following the
detection of an illegal opcode or prebyte code. Re-
fer to
tails.
7.6.1 Low Voltage Detector (LVD)
The Low Voltage Detector function (LVD) gener-
ates a static reset when the V
below a V
it secures the power-up as well as the power-down
keeping the ST7 in reset.
The V
lower than the V
on in order to avoid a parasitic reset when the
MCU starts running and sinks current on the sup-
ply (hysteresis).
The LVD Reset circuitry generates a reset when
V
The LVD function is illustrated in
The voltage threshold can be configured by option
byte to be low, medium or high.
Figure 18. Low Voltage Detector vs Reset
DD
– V
– V
V
V
RESET
is below:
IT-
IT+
IT+(LVD)
IT-(LVD)
IT-(LVD)
section 12.2.1 on page 107
(LVD)
(LVD)
IT-(LVD)
when V
when V
reference value for a voltage drop is
V
DD
IT+(LVD)
reference value. This means that
DD
DD
reference value for power-
is rising
is falling
DD
Figure
supply voltage is
for further de-
18.
Provided the minimum V
the oscillator frequency) is above V
MCU can only be in two modes:
In these conditions, secure operation is always en-
sured for the application without the need for ex-
ternal reset hardware.
During a Low Voltage Detector Reset, the RESET
pin is held low, thus permitting the MCU to reset
other devices.
Notes:
The LVD allows the device to be used without any
external RESET circuitry.
The LVD is an optional function which can be se-
lected by option byte.
Use of LVD with capacitive power supply: with this
type of power supply, if power cuts occur in the ap-
plication, it is recommended to pull V
0V to ensure optimum restart conditions. Refer to
circuit example in
note 4.
It is recommended to make sure that the V
ply voltage rises monotonously when the device is
exiting from Reset, to ensure the application func-
tions properly.
V
– under full software control
– in static safe reset
hys
Figure 106 on page 136
DD
value (guaranteed for
ST7LITE1xB
IT-(LVD)
DD
down to
DD
31/159
, the
sup-
and
1