参数资料
型号: TRF2050PW
厂商: TEXAS INSTRUMENTS INC
元件分类: PLL合成/DDS/VCOs
英文描述: PLL FREQUENCY SYNTHESIZER, 1200 MHz, PDSO20
封装: PLASTIC, SO-20
文件页数: 15/34页
文件大小: 543K
代理商: TRF2050PW
TRF2050
LOW-VOLTAGE 1.2-GHz FRACTIONAL-N/INTEGER-N SYNTHESIZER
SLWS030E– JUNE 1996 – REVISED OCTOBER 2000
22
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PRINCIPLES OF OPERATION
main divider – general (see Figure 20)
The differential RFIN inputs are amplified to internal ECL logic levels and provide excellent sensitivity (better
than –20 dBm at 1 GHz), making the prescaler ideally suited for direct interface with a VCO. The internal
dual-modulus (32/33) prescaler and counter sections divide the VCO frequency down to the reference phase
detector frequency. The prescaler division ratio (
÷32 or ÷33) is controlled by a feedback signal that is a function
of the 18-bit N-field counters. The N-field counter section is composed of two separate counters: a 5-bit
A-Counter and a 13-bit B-Counter. The prescaler divides by 33 until the A-Counter reaches terminal count and
then divides by 32 until the B-Counter reaches terminal count, whereupon both counters reset and the cycle
repeats. The following equation relates the total N division as a function of the 32/33 prescaler:
NTotal = 32 (B – A) + 33(A), where 0 ≤ A ≤ 31, and 31 ≤ B ≤ 8191.
It is not necessary to determine the values of A and B in the equation above; simply program the N field with
the total division ratio desired (fractional effects ignored).
The N-division ratio has a range of 992
≤ NTotal ≤ 262143.
32/33 Prescaler
13-Bit
B-Counter
5-Bit
A-Counter
18-Bit Register
13
5
18-Bit
Adder
18
5-Bit
Fraction Accumulator
18
4
5
5 Bits
13 Bits
N
A
B
LSB
MSB
Structure of N-Word
RFIN
N
NF
FMOD
to Phase Detector
Figure 20. Main Divider Organization
main divider – SA7025 emulation
The internal triple modulus prescaler configuration of the SA7025 provides for prescaler division ratios of
64/65/72. The TRF2050 has internal conversion logic that allows the TRF2050 to emulate the SA7025 main
divider operation. When operated in SA7025 emulation mode, the TRF2050 is programmed using the SA7025
serial interface format shown in Figure 18. The TRF2050 internal conversion is transparent and need not be
considered under normal use, thereby allowing use of existing SA7025 programming codes without change.
The following equations relate the total N-division as a function of the emulated 64/65 dual-modulus and
64/65/72 triple-modulus prescalers:
NTotal = 64 (NM1 + 2) + 65 (NM2), where PR = 01 and
NTotal = 64 (NM1 + 2) + 65 (NM2) + 72 (NM3 + 1), where PR = 10.
相关PDF资料
PDF描述
TRF2056PWR PLL FREQUENCY SYNTHESIZER, 1200 MHz, PDSO20
TRF4000 Pcs RX-mixer
TRF4002PWP 1850 MHz - 1910 MHz RF/MICROWAVE NARROW BAND MEDIUM POWER AMPLIFIER
TRS-1300-1305-8310 TRIPLE COLOR LED ARRAY
TRS-1300-1311-8310 DUAL COLOR LED ARRAY
相关代理商/技术参数
参数描述
TRF2052 制造商:TI 制造商全称:Texas Instruments 功能描述:LOW-VOLTAGE 2-GHz SYNTHESIZER
TRF2052PW 功能描述:IC LV 2-GHZ SYNTH 20-TSSOP RoHS:否 类别:集成电路 (IC) >> 时钟/计时 - 时钟发生器,PLL,频率合成器 系列:- 标准包装:2,000 系列:- 类型:PLL 频率合成器 PLL:是 输入:晶体 输出:时钟 电路数:1 比率 - 输入:输出:1:1 差分 - 输入:输出:无/无 频率 - 最大:1GHz 除法器/乘法器:是/无 电源电压:4.5 V ~ 5.5 V 工作温度:-20°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-LSSOP(0.175",4.40mm 宽) 供应商设备封装:16-SSOP 包装:带卷 (TR) 其它名称:NJW1504V-TE1-NDNJW1504V-TE1TR
TRF2056 制造商:TI 制造商全称:Texas Instruments 功能描述:LOW-VOLTAGE 1,2-GHz FRACTIONAL-N/INTEGER-N SYNTHESIZER
TRF2056PW 制造商:Rochester Electronics LLC 功能描述:- Bulk
TRF2253PWR 制造商:Texas Instruments 功能描述: