st62t25cn6 STMicroelectronics, st62t25cn6 Datasheet - Page 81

• Manufacturer Part Number: st62t25cn6
• Description: 8-bit Mcus With A/d Converter, Two Timers, Oscillator Safeguard & Safe Reset
• Manufacturer: STMicroelectronics

EMC CHARACTERISTICS (Cont’d)
11.7.3 ESD Pin Protection Strategy
To protect an integrated circuit against Electro-
Static Discharge the stress must be controlled to
prevent degradation or destruction of the circuit el-
ements. The stress generally affects the circuit el-
ements which are connected to the pads but can
also affect the internal devices when the supply
pads receive the stress. The elements to be pro-
tected must not receive excessive current, voltage
or heating within their structure.
An ESD network combines the different input and
output ESD protections. This network works, by al-
lowing safe discharge paths for the pins subjected
to ESD stress. Two critical ESD stress cases are
presented in
pins.
Figure 59. Positive Stress on a Standard Pad vs. V
Figure 60. Negative Stress on a Standard Pad vs. V
Main path
Path to avoid
Main path
Figure 59
V
V
V
V
DD
DD
SS
SS
and
Figure 60
(3a)
(3b)
(3a)
(3b)
for standard
OUT
OUT
SS
Standard Pin Protection
To protect the output structure the following ele-
ments are added:
– A diode to V
– A protection device between V
To protect the input structure the following ele-
ments are added:
– A resistor in series with the pad (1)
– A diode to V
– A protection device between V
DD
(4)
(4)
IN
IN
DD
DD
(3a) and a diode from V
(2a) and a diode from V
(2a)
(2b)
(2a)
(2b)
(1)
(1)
ST6215C/ST6225C
DD
DD
and V
and V
SS
SS
SS
SS
81/105
V
V
V
V
(3b)
(2b)
(4)
(4)
DD
SS
DD
SS
1