參數(shù)資料
型號: LMX2330UTMX/NOPB
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: PLL合成/DDS/VCOs
英文描述: PLL FREQUENCY SYNTHESIZER, 2500 MHz, PDSO20
封裝: 0.173 INCH, PLASTIC, TSSOP-20
文件頁數(shù): 38/49頁
文件大?。?/td> 4568K
代理商: LMX2330UTMX/NOPB
2.0 Programming Description (Continued)
2.4.4 TRI-STATE ID
o IF
IF Synthesizer Charge Pump Tri-state Current
IF R[19]
The TRI-STATE ID
o IF bit allows the charge pump to be switched between a normal operating mode and a high impedance output
state. This happens asynchronously with the change in the TRI-STATE ID
o IF bit.
Furthermore, the TRI-STATE ID
o IF bit operates in conjuction with the PWDN IF bit to set a synchronous or an asynchronous
powerdown mode.
Control Bit
Register Location
Description
Function
01
TRI-STATE ID
o IF
IF R[19]
IF Charge Pump
TRI-STATE Current
IF Charge Pump
Normal Operation
IF Charge Pump
Output in High
Impedance State
2.5 IF N REGISTER
The IF N register contains the IF N_CNTRA, IF N_CNTRB, PRE IF, and PWDN IF control words. The IF N_CNTRA and IF
N_CNTRB control words are used to setup the programmable feedback divider. The detailed description and programming
information for each control word is discussed in the following sections.
Reg. Most Significant Bit
SHIFT REGISTER BIT LOCATION
Least Significant Bit
21
20
19
18
17
16
15
14
13
12
11
10
9876543210
Data Field
Address
Field
IF
N
PWDN
IF
PRE
IF
IF N_CNTRB[10:0]
IF N_CNTRA[6:0]
0
1
2.5.1 IF N_CNTRA[6:0]
IF Synthesizer Swallow Counter (A Counter)
IF N[2:8]
The IF N_CNTRA control word is used to setup the IF synthesizer’s A counter. The A counter is a 7-bit swallow counter used in
the programmable feedback divider. The IF N_CNTRA control word can be programmed to values ranging from 0 to 15. The three
most significant bits are ‘don’t care bits’ in this case.
Divide Ratio
IF N_CNTRA[6:0]
6543210
0
X
0000
1
X
0001
15
X
1111
2.5.2 IF N_CNTRB[10:0]
IF Synthesizer Programmable Binary Counter (B Counter)
IF N[9:19]
The IF N_CNTRB control word is used to setup the IF synthesizer’s B counter. The B counter is an 11-bit programmable binary
counter used in the programmable feedback divider. The IF N_CNTRB control word can be programmed to values ranging from
3 to 2047.
Divide
Ratio
IF N_CNTRB[10:0]
10
9876543210
300000000011
400000000100
2047
11111111111
2.5.3 PRE IF
IF Synthesizer Prescaler Select
IF N[20]
The IF synthesizer utilizes a selectable dual modulus prescaler.
Control Bit
Register Location
Description
Function
01
PRE IF
IF N[20]
IF Prescaler Select
8/9 Prescaler
Selected
16/17 Prescaler
Selected
LMX2330U/LMX2331U/LMX2332U
www.national.com
43
相關(guān)PDF資料
PDF描述
LMX2335LTMX/NOPB PLL FREQUENCY SYNTHESIZER, 1100 MHz, PDSO16
LMX2335LMX PLL FREQUENCY SYNTHESIZER, 1100 MHz, PDSO16
LMX2335LTM/NOPB PLL FREQUENCY SYNTHESIZER, 1100 MHz, PDSO16
LMX2336LTMX/NOPB PLL FREQUENCY SYNTHESIZER, 2000 MHz, PDSO20
LMX2336LTM/NOPB PLL FREQUENCY SYNTHESIZER, 2000 MHz, PDSO20
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LMX2331 制造商:NSC 制造商全稱:National Semiconductor 功能描述:PLLatinum⑩ Low Power Dual Frequency Synthesizer for RF Personal Communications
LMX2331 WAF 制造商:Texas Instruments 功能描述:
LMX2331A 制造商:NSC 制造商全稱:National Semiconductor 功能描述:PLLatinum⑩ Dual Frequency Synthesizer for RF Personal Communications
LMX2331ATM 制造商:Texas Instruments 功能描述:
LMX2331ATMX 功能描述:IC FREQ SYNTH DUAL 20-TSSOP RoHS:否 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:PLLatinum™ 標準包裝:39 系列:- 類型:* PLL:帶旁路 輸入:時鐘 輸出:時鐘 電路數(shù):1 比率 - 輸入:輸出:1:10 差分 - 輸入:輸出:是/是 頻率 - 最大:170MHz 除法器/乘法器:無/無 電源電壓:2.375 V ~ 3.465 V 工作溫度:0°C ~ 70°C 安裝類型:* 封裝/外殼:* 供應(yīng)商設(shè)備封裝:* 包裝:*