Electrical characteristics
STM32F042x4 STM32F042x6
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DocID025832 Rev 5
Software recommendations
The software flowchart must include the management of runaway conditions such as:
•
Corrupted program counter
•
Unexpected reset
•
Critical Data corruption (for example 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 NRST 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).
Electromagnetic Interference (EMI)
The electromagnetic field emitted by the device are monitored while a simple application is
executed (toggling 2 LEDs through the I/O ports). This emission test is compliant with
IEC 61967-2 standard which specifies the test board and the pin loading.
6.3.12 Electrical
sensitivity characteristics
Based on three different tests (ESD, LU) using specific measurement methods, the device is
stressed in order to determine its performance in terms of electrical sensitivity.
Electrostatic discharge (ESD)
Electrostatic discharges (a positive then a negative pulse separated by 1 second) are
applied to the pins of each sample according to each pin combination. The sample size
depends on the number of supply pins in the device (3 parts × (n+1) supply pins). This test
conforms to the JESD22-A114/C101 standard.
Table 46. EMI characteristics
Symbol
Parameter
Conditions
Monitored
frequency band
Max vs. [f
HSE
/f
HCLK
]
Unit
8/48 MHz
S
EMI
Peak level
V
DD
= 3.6 V, T
A
= 25 °C,
LQFP48 package
compliant with
IEC 61967-2
0.1 to 30 MHz
-9
dBµV
30 to 130 MHz
9
130 MHz to 1 GHz
17
EMI Level
3
-
