Electrical characteristics

ST7GEME4

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Software recommendations

The software flowchart must include the management of runaway conditions such as:

●

Corrupted program counter

●

Unexpected reset

●

Critical Data corruption (control registers...)

Prequalification trials

Most of the common failures (unexpected reset and program counter corruption) can be

reproduced by manually forcing a low state on the RESET pin or the Oscillator pins for 1

second.

To complete these trials, ESD stress can be applied directly on the device, over the range of

specification values. When unexpected behavior is detected, the software can be hardened

to prevent unrecoverable errors occurring (see application note AN1015).

4.7.2

Electromagnetic interference (EMI)

Based on a simple application running on the product (toggling 2 LEDs through the I/O

ports), the product is monitored in terms of emission. This emission test is in line with the

norm SAE J 1752/3 which specifies the board and the loading of each pin.

Table 19.

EMS characteristics

Symbol

Parameter

Conditions

Level/

Class

Voltage limits to be applied on any I/O pin to

induce a functional disturbance

conforms to IEC 1000-4-2

2B

Fast transient voltage burst limits to be

to induce a functional disturbance

conforms to IEC 1000-4-4

4B

Table 20.

EMI characteristics

Symbol

Parameter

Conditions

Monitored

frequency band

Max vs.

(1)

1.

Data based on characterization results, not tested in production.

Unit

4/8MHz 4/4MHz

Peak level

conforming to SAE J 1752/3

0.1 MHz to

30 MHz

19

18

dB

µ

V

30 MHz to

130 MHz

32

27

130 MHz to

1GHz

31

26

SAE EMI Level

4

3.5

-