- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄369901 > MC44818D (MOTOROLA INC) TV AND VCR PLL TUNING CIRCUIT WITH 1.3 GHz PRESCALER AND I2C BUS PDF資料下載
參數(shù)資料
| 型號： | MC44818D |
| 廠商： | MOTOROLA INC |
| 元件分類： | XO, clock |
| 英文描述： | TV AND VCR PLL TUNING CIRCUIT WITH 1.3 GHz PRESCALER AND I2C BUS |
| 中文描述： | PLL FREQUENCY SYNTHESIZER, 1300 MHz, PDSO16 |
| 封裝： | PLASTIC, SO-16 |
| 文件頁數(shù)： | 5/8頁 |
| 文件大?。?/td> | 158K |
| 代理商： | MC44818D |
MC44818
5
MOTOROLA ANALOG IC DEVICE DATA
Bit T14: Controls the Charge Pump Current of the
Bit T14:
Phase Comparator
T14 = 0
T13
= 1
Pump Current 50
μ
A Typical
Pump Current 15
μ
A Typical
The Programmable Divider
The programmable divider is a presettable down counter.
When it has counted to zero it takes its required division ratio
out of the latches B. Latches B are loaded from latches A by
means of signal TDI which is synchronous to the
programmable divider output signal.
Since latches A receive the data asynchronously with the
programmable divider; this double latch scheme is needed to
assure correct data transfer to the counter.
The division ratio definition is given by:
N = 16384 x N14 + 8192 x N13 +
…
+ 4 x N2 + 2 x N1 + N0
Maximum Ratio 32767
Minimum Ratio 17
N0
…
N14 are the different bits for frequency information.
At power “on” the whole bus receiver is reset and the
programmable divider is set to a counting ratio of N = 256 or
higher.
The Prescaler
The prescaler has a preamplifier which guarantees high
input sensitivity.
The Phase Comparator
The phase comparator is phase and frequency sensitive
and has very low output leakage current in the high
impedance state.
Lock Detector
The lock detector output is low in lock. The output goes
immediately high when an unlock condition is detected. The
output goes low again when the loop is in lock during a
complete period of the reference frequency.
Figure 4. Equivalent Circuit of the Lock Output
2.0 k
25 V Protection
Lock
VCC1 5.0 V
100 k
200
μ
A Typical
The Operational Amplifier
The operational amplifier is designed for very low noise,
low input bias current and high power supply rejection. The
positive input is biased internally. The operational amplifier
needs 28.5 V supply (VCC2) as minimum voltage for a
guaranteed maximum tuning voltage of 28 V.
Figure NO TAG shows a possible filter arrangement. The
component values depend very much on the application
(tuner characteristic, reference frequency, etc.).
The Oscillator
The oscillator uses a 3.2 to 4.0 MHz crystal tied to ground in
series with a capacitor. The crystal operates in the series
resonance mode.
The voltage at Pin 3 has low amplitude and low harmonic
distortion.
1.0 nF
÷
8
Pres
Figure 5. Typical Tuner Application
11
12
13
10
B3
B2
B1
B0
12 pF
3.2/4.0 MHz
Gnd
9
6
5
4
15
Lock
B III
VHF
UHF
AGC
VTUN
33 V
Phase
Comp
Program
Divider
2.7 V
Mixer
B. P. Filter
Antenna
Filter
Oscillator
IF
7
5.0 V
2
1
16
3
Osc &
Ref Div
Fosc
SCL
SDA
AS
VCC3
14 12 V
Bus
Rec
22 nF
47 k
(Note 1)
(Note 2)
330 p
47 nF
NOTES:
1.On some layouts the 100
resistor will not be required.
2.C2 = 330 pF minimum is required for stability.
External Switching
MC44818
8
相關PDF資料 |
PDF描述 |
|---|---|
| MC44818 | TV AND VCR PLL TUNING CIRCUIT WITH 1.3 GHz PRESCALER AND I2C BUS |
| MC44824D | RW-S Series - Econoline Regulated DC-DC Converters; Input Voltage (Vdc): 12V; Output Voltage (Vdc): 15V; Power: 2W; DIP24 Low Profile Miniature Package; 1kVDC Isolation; Feedback Regulated Output; 2:1 Wide Range Voltage Input; Continuous Short Circuit Protection; Less than 7mm Height; SMD Pinning Option; Efficiency to 87% |
| MC44825D | TV AND VCR PLL TUNING CIRCUITS WITH 1.3 GHz PRESCALER AND I2C BUS |
| MC44826D | TV AND VCR I2C PLL TUNING CIRCUIT WITH 1.3 GHz PRESCALER AND MIX/OSC DECODER |
| MC44827BDTB | LOW-POWER PLL TUNING CIRCUIT |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| MC44818DR2 | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| MC44824D | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:TV AND VCR PLL TUNING CIRCUITS WITH 1.3 GHz PRESCALER AND I2C BUS |
| MC44825D | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:TV AND VCR PLL TUNING CIRCUITS WITH 1.3 GHz PRESCALER AND I2C BUS |
| MC44826D | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:TV AND VCR I2C PLL TUNING CIRCUIT WITH 1.3 GHz PRESCALER AND MIX/OSC DECODER |
| MC44827 | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:LOW-POWER PLL TUNING CIRCUIT |
發(fā)布緊急采購，3分鐘左右您將得到回復。