[AK4955]
Parameter
min
typ
max
Unit
Video Signal Input
External Resistor (Note 21) R1 (Figure 2)
-
-
600
0.2
1.24
-
Ω
μF
Vpp
External Capacitor
C1 (Figure 2)
0.05
-
-
0.1
1.0
0.5
Maximum Input Voltage: VG1-0 bits = “00” (+6dB)
Pull Down Current
μA
Video Analog Output (Figure 3)
Output Gain
fin =100kHz
Sine wave Input
(Note 20)
VG1-0 bits = “00”, 1.0Vpp Input
VG1-0 bits = “01”, 0.7Vpp Input
VG1-0 bits = “10”, 0.5Vpp Input
VG1-0 bits = “11”, 0.3Vpp Input
Signal Input
5.5
8.5
11.5
16
6.0
9.0
12.0
16.5
6.5
9.5
12.5
17
dB
0
100
mV
mV
dB
DC Output Offset Level
(Note 20)
−100
-
(Pedestal Level)
No Signal Input
BW = 100kH ∼ 6MHz,
S = 0.7Vpp Input
-
-
−572
70
S/N (Note 22)
60
VG1-0 bits = “00”(+6dB)
Maximum Output Voltage
(Note 20)
Secondary Harmonic Distortion
VG1-0 bits = “00”(+6dB), fin = 3.58MHz,
fin =100kHz (Sine wave)
2.62
-
-
-
Vpp
dB
−40
−30
1.0Vpp: −40 ~ 100IRE, Sine Wave Input
Load Resistance
Load Capacitance
140
150
-
-
58
53
-
15
400
-
Ω
C2 (Figure 3)
-
-
-
-
pF
pF
dB
dB
C3 (Figure 3)
fin = 10kHz
fin = 100kHz
PSRR
VG1-0 bits = “00”(+6dB)
-
LPF for VIN signal : (Note 20)
Frequency Response (fin = 100kHz, 1.0Vpp, Sine wave Input)
Response at 6.75MHz
+2.0
−20
100
−3.0
-
-
−0.5
−40
15
dB
ns
Response at 27MHz
Group Delay
|GD3MHz−GD6MHz|
Note 20. This is a value at measurement point in Figure 3. 1.0Vpp input is the value when VG1-0 bits =“00”. Input
amplitude is in inverse proportion to the gain. S/N is measured at measuring point 2.
Note 21. PMV bit must be set to “0” if the input impedance of the VIN pin exceeds 600Ω in case of the input signal is
stopped or the input circuit of the VIN pin is powered down.
Note 22. S/N = 20xlog (Output Voltage[Vpp]/Noise Level[Vrms]). Output Voltage = 0.7 [Vpp].
VIN pin
From Video DAC
AK4955
R1
C1
Figure 2. External Resistor of Video Signal Input pin
Measurement point1
75 ohm
Measurement point2
Video Signal Output
R3
R2
75 ohm
C2
C3
Figure 3. Load Capacitance C2 and C3
MS1343-E-00
2011/12
- 11 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
