USB6Bx
TECHNICAL INFORMATION
SURGE PROTECTION
The USB6Bx is particularly optimized to perform
surge protection based on the rail to rail topology.
The clamping voltage VCL can be estimated as follow:
VCL+ =Vcc + VF for positive surges
VCL - = - VF
for negative surges
with: VF = Vt + rd.Ip
(VF forward drop voltage) / (Vt forward drop
threshold voltage)
Note: the estimations do not take into account
phenomena due to parasitic inductances.
Fig. A1 :
ESD
SURGE
Lw
Lw di
Vf
dt
I/O
+Vcc
VI/O
Lw di
dt
Vcl+ =
Vcc+Vf+
Lw
di
dt
surge >0
Vcl- =
-Vf-
Lw
di
dt
surge <0
GND
Vcl+
Lw di
dt
POSITIVE
SURGE
Vcc+Vf
t
tr=1ns
tr=1ns
t
-Vf
-Lw di
dt
NEGATIVE
SURGE
Vcl-
2/9