Datasheet

Electrical characteristics STM32F051x
68/105 Doc ID 022265 Rev 3
Static latch-up
Two complementary static tests are required on six parts to assess the latch-up
performance:
● A supply overvoltage is applied to each power supply pin
● A current injection is applied to each input, output and configurable I/O pin
These tests are compliant with EIA/JESD 78A IC latch-up standard.
6.3.12 I/O current injection characteristics
As a general rule, current injection to the I/O pins, due to external voltage below V
SS
or
above V
DD
(for standard, 3 V-capable I/O pins) should be avoided during normal product
operation. However, in order to give an indication of the robustness of the microcontroller in
cases when abnormal injection accidentally happens, susceptibility tests are performed on a
sample basis during device characterization.
Functional susceptibility to I/O current injection
While a simple application is executed on the device, the device is stressed by injecting
current into the I/O pins programmed in floating input mode. While current is injected into the
I/O pin, one at a time, the device is checked for functional failures.
The failure is indicated by an out of range parameter: ADC error above a certain limit (>5
LSB TUE), out of conventional limits of current injection on adjacent pins (lower than
–5µA
or lower than − 10 µA), or other functional failure (for example reset, oscillator frequency
deviation).
The characterization results are given in Ta ble 4 9 .
Table 48. Electrical sensitivities
Symbol Parameter Conditions Class
LU Static latch-up class T
A
= +105 °C conforming to JESD78A II level A
Table 49. I/O current injection susceptibility
Symbol Description
Functional susceptibility
Unit
Negative
injection
Positive
injection
I
INJ
Injected current on BOOT0, PF0-OSC_IN
and PF1-OSC_OUT pins
–0 NA
mA
Injected current on PA10, PA12, PB4, PB5,
PB10, PB15 and PD2 with current injection
on adjacent pins > –5 µA and <–10 µA
–5 NA
Injected current on other FT and FTf pins
with current injection on adjacent pins
<–5 µA
–5 NA
Injected current on PA6 and PC0 pins –0 +5
Injected current on all other TTa pins –5 +5
Injected current on TC and RST pins –5 +5