Technical Note
5/8
BH76106HFV, BH76109HFV, BH76112HFV, BH76206HFV
www.rohm.com
2009.03 - Rev.A
© 2009 ROHM Co., Ltd. All rights reserved.
(11) SAG correction
In order to make the SAG of the video signal as small as possible, we recommend the values of the application circuit
diagram for output coupling capacitor capacitance.
If reducing capacitance due to the demands of miniaturization or the like, check the SAG characteristic for an
alternating black and white bounce signal *1, Hbar signal *2, or other signal for which a SAG effect readily occurs and
use a capacitance that satisfies the demands of the set being used.
As a reference, try the combinations shown below when reducing capacitance. As the capacitance of the V
OUT
capacitor is made smaller, SAG becomes greater.
*1,*2: TG-7 U705 unit or other
V
sag Capacitor (C1)
33μF 33μF 33μF
VOUT Capacitor (C2)
68μF 47μF 33μF
(12) Using after removing output coupling capacitor
An application circuit that is an example of use after removing the output coupling capacitor is shown in the figure
below.
By eliminating the output coupling capacitor, not only can you reduce board space and product cost, but improvement
of the SAG characteristic also can be realized due to the fact that the low-band frequency characteristic is improved.
However, since direct current will flow in a set connected on the opposite side due to eliminating the output coupling
capacitor, pay close attention to the specifications of what is connected in conjunction with using it.
Moreover, characteristics such as circuit current, differential gain, and differential phase differ as shown below.
Parameter With Output Coupling Capacitor Without Output Coupling Capacitor
Circuit Current (If no signal) 7.1 mA 7.8 mA
Circuit Current (If color bar signal output) 8.3 mA 14.3 mA
Differential Gain (DG) 0.7% 1.0%
Differential Phase (DP) 0.7° 0.3°
The values shown above are reference values. They are not guaranteed values.
(13) Output dynamic range
The output dynamic range depends on the power supply voltage.
Be careful when using the LSI at low voltage.
The relationship of dynamic range to V
cc is shown in Fig. 19.
１．When input coupling capacitor (②) is 0.1 μF
Time until output voltage stabilizes (③): 214 ms
２. When input coupling capacitor (②) is 0.56 μF
Time until output voltage stabilizes (③): 1.11 s
３. When input coupling capacitor (②) is 1 μF
Time until output voltage stabilizes (③): 2.03 s
Input
waveform
Output
waveform
1 V/DIV
500 ms/DIV
①
③
Fig10 Relationship of Output Voltage
to Input Voltage
(For BH76106HFV C
in=1uF)
1
2
3
8th order
LPF
Sync_Tip
CFFi
.2
AMP
75Ω
5
4
7Fig.
85C
75Ω
0.1μF
VCC
BH76106/109/
112/206HFV
GND
Standby
6
Fig.11
