- 您现在的位置：买卖IC网 > PDF目录370133 > 74VHC4046NX (National Semiconductor Corporation) CMOS Phase Lock Loop PDF资料下载
参数资料
| 型号： | 74VHC4046NX |
| 厂商： | National Semiconductor Corporation |
| 英文描述： | CMOS Phase Lock Loop |
| 中文描述： | 的CMOS锁相环 |
| 文件页数： | 9/14页 |
| 文件大小： | 283K |
| 代理商： | 74VHC4046NX |
Detailed Circuit Description
(Continued)
the capacitor once the capacitor charges up to the thresh-
old of the schmitt trigger the oscillator logic flips the capaci-
tor over and causes the mirror to charge the opposite side
of the capacitor. The output from the internal logic is then
taken to pin 4.
The input to the VCO is a very high impedance CMOS input
and so it will not load down the loop filter, easing the filters
design. In order to make signals at the VCO input accessible
without degrading the loop performance a source follower
transistor is provided. This transistor can be used by con-
necting a resistor to ground and its drain output will follow
the VCO input signal.
An inhibit signal is provided to allow disabling of the VCO
and the source follower. This is useful if the internal VCO is
not being used. A logic high on inhibit disables the VCO and
source follower.
The output of the VCO is a standard high speed CMOS
output with an equivalent LSTTL fanout of 10. The VCO
output is approximately a square wave. This output can ei-
ther directly feed the comparator input of the phase compar-
ators or feed external prescalers (counters) to enable fre-
quency synthesis.
PHASE COMPARATORS
All three phase comparators share two inputs, Signal In and
Comparator In. The Signal In has a special DC bias network
that enables AC coupling of input signals. If the signals are
not AC coupled then this input requires logic levels the
same as standard 74VHC. The Comparator input is a stan-
dard digital input. Both input structures are shown in Figure
3.
The outputs of these comparators are essentially standard
74VHC voltage outputs. (Comparator II is TRI-STATE.)
TL/F/11675-19
FIGURE 3. Logic Diagram for Phase Comparator I and the Common Input Circuit for All Three Comparators
TL/F/11675–20
FIGURE 4. Typical Phase Comparator I. Waveforms
9
相关PDF资料 |
PDF描述 |
|---|---|
| 74VHC4046MTC | CMOS Phase Lock Loop |
| 74VHC4046 | CMOS Phase Lock Loop |
| 74VHC4046M | CMOS Phase Lock Loop |
| 74VHC4046N | 3-Line To 8-Line Decoders/Demultiplexers 16-TSSOP -40 to 85 |
| 74VHC4046MTCX | Code Hopping Encoder 3.5- 13V, -40C to +85C, 8-SOIC 150mil, T/R |
相关代理商/技术参数 |
参数描述 |
|---|---|
| 74VHC4051 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:8-Channel Analog Multiplexer . Dual 4-Channel Analog Multiplexer . Triple 2-Channel Analog Multiplexer |
| 74VHC4051AFT | 功能描述:1 Circuit IC Switch 8:1 37 Ohm 16-TSSOPB 制造商:toshiba semiconductor and storage 系列:- 包装:剪切带（CT） 零件状态:有效 开关电路:- 多路复用器/解复用器电路:8:1 电路数:1 导通电阻（最大值）:37 欧姆 通道至通道匹配（ΔRon）:5 欧姆 电压 -?电源，单（V+）:2 V ~ 5.5 V 电压 - 电源，双（V±）:- 开关时间（Ton, Tof）（最大值）:12ns，12ns -3db 带宽:180MHz 电荷注入:- 沟道电容 （CS(off），CD（off））:0.5pF，23.4pF 电流 - 漏泄（IS（off））（最大值）:100nA 串扰:-45dB @ 1MHz 工作温度:-40°C ~ 85°C（TA） 封装/外壳:16-TSSOP（0.173"，4.40mm 宽） 供应商器件封装:16-TSSOPB 标准包装:1 |
| 74VHC4051M | 功能描述:多路器开关 IC 8-Chan Ana Multiplex RoHS:否 制造商:Texas Instruments 通道数量:1 开关数量:4 开启电阻（最大值）:7 Ohms 开启时间（最大值）: 关闭时间（最大值）: 传播延迟时间:0.25 ns 工作电源电压:2.3 V to 3.6 V 工作电源电流: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:UQFN-16 |
| 74VHC4051M_Q | 功能描述:多路器开关 IC 8-Chan Ana Multiplex RoHS:否 制造商:Texas Instruments 通道数量:1 开关数量:4 开启电阻（最大值）:7 Ohms 开启时间（最大值）: 关闭时间（最大值）: 传播延迟时间:0.25 ns 工作电源电压:2.3 V to 3.6 V 工作电源电流: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:UQFN-16 |
| 74VHC4051MTC | 功能描述:多路器开关 IC 8-Chan Ana Multiplex RoHS:否 制造商:Texas Instruments 通道数量:1 开关数量:4 开启电阻（最大值）:7 Ohms 开启时间（最大值）: 关闭时间（最大值）: 传播延迟时间:0.25 ns 工作电源电压:2.3 V to 3.6 V 工作电源电流: 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:UQFN-16 |
发布紧急采购，3分钟左右您将得到回复。