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3. Phase Comparator and Unlock Port Circuit Configuration
Reference frequency
基準周波数
Programmable counter
プログラマブル
output
カウンタ出力
UNLOCK RESET
Programmable
プログラマブル
counter clock
カウンタクロック
CK0,CK1
Note: The phase comparator circuit block uses the V
is outputted as the "H" level of the phase comparator output pin (DO).
converter
VT
10KΩ
VCOの
To vari-cap
of VCO
バリキャップへ
外部ローパスフィルタアンプ回路例
Example of external low-pass filter amplifier circuit
Note: The phase comparator pin has a built-in resistor. Add an output resistor if needed.
Note: For details of the DC-DC converter, refer to the section on the DC-DC converter for VT. When the DCK1
internal doubler transistor is used for the DC-DC converter voltage, design the tuner circuit to widen the
variable range of the tuning voltage (VT).
Note: In the PLL off mode, the phase comparator output (DO1/2) will be "Hz". When the external low-pass filter
(LPF) is used, the external LPF base potential will be unfixed, and the consumption current will increase
from the power supply (V
comparator output (DO1/2) to the "L" level output.
Note: The filter circuit constants shown above are for reference only. Examine and design actual circuits
according to the system band configuration and your desired characteristics.
V
VDB
DB
Phase
位相比較器
comparator
UNLOCK
UNLOCK
ENABLE
F/F
Phase difference
位相差カウンタ
counter
R0,R1
DC-DC
DC-DC
Power supply
電源
コンバータ
電源
(V
)
（ VDD)
DD
470pF
1uF
4.7KΩ
Note
) through the transistor. In the tuner off state (PLL off mode), fix the phase
DD
V
VDB
DB
R0,R1
PN POLビット
、
PN and POL bits
V
VDB
DB
LPF ON
AUTO
P9-0 output data
P9-0出力データ
power supply. Therefore, the V
DB
～
To vari-cap
VCOの
of VCO
バリキャップへ
DO2
54
注
Example of built-in low-pass filter amplifier circuit
108
TC9349AFG
～
53
DO1/OT1/P
54
DO2/OT2/N/TIN
55
P9-0/Tout
power supply level
DB
55
Tin
VT
54
Tout
10kΩ
0.01uF
DC-DC
DC-DC
converter
コンバータ
内蔵ローパスフィルタアンプ回路例
2006-02-24
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