MAX4399CTK Maxim, MAX4399CTK Datasheet - Page 19

• Manufacturer Part Number: MAX4399CTK
• Description: Audio/Video Switch for Three SCART Connectors
• Manufacturer: Maxim

The MAX4399 features high-ESD protection on all
SCART inputs and outputs, and requires no external
transient voltage suppressor (TVS) devices to protect
against floating chassis discharge. Some set-top boxes
have a floating chassis problem in which the chassis is
not connected to earth ground. As a result, the chassis
can charge up to 500V. When a SCART cable is con-
Figure
Hot-Plug of SCART Connectors—Floating
MPEG DECODER
9. MPEG Decoder Outputs Filtered by the MAX7440 Before Being Passed to the MAX4399
CVBS
C
G
Y
R
B
D/A
D/A
D/A
D/A
D/A
D/A
0.1µF
______________________________________________________________________________________
+5V
1µF
Audio/Video Switch for Three SCART
IN1
IN2
IN3
IN4
IN5
IN6
Chassis Discharge
LOWPASS FILTER
LOWPASS FILTER
LOWPASS FILTER
LOWPASS FILTER
LOWPASS FILTER
LOWPASS FILTER
MAX7440
A = +1V/V
A = +1V/V
A = +1V/V
A = +1V/V
A = +1V/V
A = +1V/V
nected to the SCART connector, the charged chassis
can discharge through a signal pin. The equivalent cir-
cuit is a 2200pF capacitor charged to 311V connected
through less than 0.1Ω to a signal pin. The MAX4399 is
soldered on the PC board when it experiences such a
discharge. Therefore, the current spike flows through
the ESD protection diodes and is absorbed by the sup-
ply bypass capacitors, which have high capacitance
and low ESR.
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
0.1µF
0.1µF
0.1µF
0.1µF
0.1µF
0.1µF
ENC_Y/CVBS_IN
ENC_R/C_IN
ENC_Y_IN
ENC_C_IN
ENC_G_IN
ENC_B_IN
CLAMP
CLAMP
CLAMP
CLAMP
CLAMP
BIAS
Connectors
MAX4399
G_VID
V_VID
+5V
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