sm5301a Nippon Precision Circuits Inc, (NPC), sm5301a Datasheet - Page 10

• Manufacturer Part Number: sm5301a
• Description: 3-channel Video Buffer With Built-in Wideband Filters
• Manufacturer: Nippon Precision Circuits Inc, (NPC)

TYPICAL APPLICATION CIRCUITS
ATSC Digital TV Application
(*1) Pins without an input signal, set by NUXSEL, should be left open or tied to GND.
(*2) Connect 4 × 0.1µF capacitor between the supply pins close to the IC.
(*3) Connect a 47µF capacitor between the supply pins close to the IC.
(*4) GS×1 are 3-level pins. Connect a capacitor if an error occurs due to external noise. Also, if open-circuit,
(*5) Printed circuit board supply wiring
Input Capacitor and Cutoff Frequency
The capacitor connected to pins R
forms a highpass filter (HPF) with the internal impedance.
The HPF cutoff frequency is given by the following equation.
(C: input capacitance, R: signal input impedance = 9.3kΩ)
DISABLE
the internal impedance and external capacitance (C) form an RC network. When power is applied, the
open-circuit potential rises with time constant τ = C × 10k (sec).
I
I
I
G
R
B
SYNC
GSG1
GSR1
IN
GSB1
IN
IN
If the supply is used for other digital circuits, there is a possibility that noise will be introduced. Accord-
ingly, these circuits should be connected to the application’s analog supply.
Ground-plane wiring should be performed, as much as possible, to provide low GND line impedance.
If ground-plane wiring up to the GND pins is difficult, the ground plane should be as close to the IC as
possible with a separate wire to each GND pin.
/Y
/U
/V
fc =
IN
IN
IN
1.0µF
1.0µF
1.0µF
2πCR
(*4)
1
(*4)
(*4)
(*1)
(*1)
control voltage
INA
Cut-off
/Y
INA
(*1)
, R
INB
SM5301AS
/Y
INB
, G
INA
/U
(*2)
(*2)
INB
, G
INB
(*3)
(*2)
/U
(*2)
INB
SEIKO NPC CORPORATION —10
, B
+5V
220µF
220µF
220µF
INA
+
+
+
/V
75Ω
75Ω
75Ω
INA
, and B
INB
R/Y
G/U
B/V
/V
INB