AK4252_10 Datasheet, PDF (5/8 Pages) Asahi Kasei Microsystems – Output Coupling Capacitor-less Video Amp with LPF

[AK4252]
■ Video Block
The Video Amp has drivability for a load resistance of 150Ω. The AK4252 has a composite input and output and includes
a low pass filter (LPF). Internal negative power supply circuit supplies negative voltage to the video amp and video amp
0V output is used for a pedestal level. Therefore, the output coupling capacitor can be removed.
A K4 252
VDD
Charge
Pump
Negative Power
CP
CN VSS
VEE
C2
(+)
1 uF
1uF C1
(+)
Note 6. C1 and C2 capacitors should have the low ESR (Equivalent Series Resistance) over all temperature range. When
these capacitors have the polarity, the positive polarity pin should be connected to the CP pin and the VSS pin.
Non polarity capacitors can also be used.
Figure 3. Negative Power Supply circuit
AK4252
7 5Ω
VOUT
75Ω
0V
Figure 4. Video signal output
■ Power Down Control
When the PDN pin is “L”, the AK4252 is forced to Power Down Mode (Power consumption: typ 1μA). The VOUT pin
becomes Hi-Z at the PDN pin = “L”. The AK4252 includes a power-on-reset function. Therefore any external reset is not
required.
MS1091-E-01
-5-
2010/04