ST7FL15F1MAE STMICROELECTRONICS [STMicroelectronics], ST7FL15F1MAE Datasheet - Page 119

• Manufacturer Part Number: ST7FL15F1MAE
• Description: 8-bit MCU for automotive with single voltage Flash/ROM memory, data EEPROM, ADC, 5 timers, SPI
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

CONTROL PIN CHARACTERISTICS (cont’d)
Figure 94. RESET Pin Protection When LVD Is Enabled
Figure 95. RESET Pin Protection When LVD Is Disabled
Note 1:
Note 2: When the LVD is enabled, it is recommended not to connect a pull-up resistor or capacitor. A 10nF pull-down
capacitor is required to filter noise on the reset line.
Note 3: If a capacitive power supply is used, it is recommended to connect a 1MΩ pull-down resistor to the RESET pin
to discharge any residual voltage induced by the capacitive effect of the power supply (this adds 5µA to the power con-
sumption of the MCU).
Note 4: Tips when using the LVD:
Note 5: Please refer to
EXTERNAL
– The reset network protects the device against parasitic resets.
– The output of the external reset circuit must have an open-drain output to drive the ST7 reset pad. Otherwise the
– Whatever the reset source is (internal or external), the user must ensure that the level on the RESET pin can go
– Because the reset circuit is designed to allow the internal RESET to be output in the RESET pin, the user must en-
– 1. Check that all recommendations related to ICCCLK and reset circuit have been applied (see caution in
– 2. Check that the power supply is properly decoupled (100nF + 10µF close to the MCU). Refer to AN1709 and
– 3. The capacitors connected on the RESET pin and also the power supply are key to avoid any start-up marginality.
RESET
device can be damaged when the ST7 generates an internal reset (LVD or watchdog).
below the V
internally.
sure that the current sunk on the RESET pin is less than the absolute maximum value specified for I
section 13.2.2 on page
on page 5
AN2017. If this cannot be done, it is recommended to put a 100nF + 1MΩ pull-down on the RESET pin.
In most cases, steps 1 and 2 above are sufficient for a robust solution. Otherwise: Replace 10nF pull-down on the
RESET pin with a 5µF to 20µF capacitor.”
Required
EXTERNAL
CIRCUIT
RESET
USER
Required
and notes above)
IL
maximum level specified in
0.01µF
section 12.2.1 on page 95
0.01µF
99.
1MΩ
Optional
(note 3)
section 13.9.1 on page
V
DD
for more details on illegal opcode reset conditions.
R
V
DD
ON
Filter
R
ON
Filter
GENERATOR
PULSE
1)2)3)4)
1)
118. Otherwise the reset is not taken into account
GENERATOR
PULSE
WATCHDOG
ILLEGAL OPCODE
ST7L15, ST7L19
WATCHDOG
ILLEGAL OPCODE
LVD RESET
INTERNAL
RESET
INTERNAL
RESET
ST7
INJ(RESET)
ST7
5)
119/138
Table 1
5)
in