ST7MC1K2-Auto datasheet(333/371 Pages) STMICROELECTRONICS

333 / 371 page

Obsolete

Product(s)

- Obsolete

Product(s)

ST7MC1K2-Auto, ST7MC1K6-Auto, ST7MC2S4-Auto, ST7MC2S6-Auto

Electrical characteristics

333/371

Figure 145. RESET pin protection when LVD is enabled(1)(2)(4)

- 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 device

can be damaged when the ST7 generates an internal reset (LVD, illegal opcode or watchdog).

- Whatever the reset source is (internal or external), the user must ensure that the level on the RESET pin can go below the

VIL max. level specified in Section 12.9.1: Asynchronous RESET pin on page 332. Otherwise the reset is not taken into

account internally.

- Because the reset circuit is designed to allow the internal RESET to be output in the RESET pin, the user must ensure

that the current sunk on the RESET pin is less than the absolute maximum value specified for IINJ(RESET) in Section 12.2.2:

Current characteristics on page 314.

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.

In case a capacitive power supply is used, it is recommended to connect a 1M

Ω 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

consumption of the MCU).

Tips when using the LVD:

A. Check that all recommendations related to ICCCLK and reset circuit have been applied (see notes above)

B. Check that the power supply is properly decoupled (100nF + 10µF close to the MCU). Refer to AN1709 and AN2017. If

this cannot be done, it is recommended to put a 100nF + 1M

Ω pull-down on the RESET pin.

C. The capacitors connected on the RESET pin and also the power supply are key to avoid any start-up marginality. 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.”

Please refer to Section 11.2.2: Illegal opcode reset for more details on illegal opcode reset conditions

0.01µF

Pulse

generator

Filter

RON

VDD

Watchdog

LVD reset

Internal

reset

External

Required

Ω

Optional(3)

Illegal opcode(5)

ST7MC1K2-Auto

ST7MC1K6-Auto

ST7MC2S4-Auto

ST7MC2S6-Auto

Obsolete

Product(s)

- Obsolete

Product(s)

ST7MC1K2-Auto bảng dữ liệu(PDF) 333 Page - STMicroelectronics

ST7MC1K2-Auto bảng dữ liệu(HTML) 333 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

bảng dữ liệu tải về

Link URL