- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄296330 > LTC6990IS6#TRPBF (LINEAR TECHNOLOGY CORP) VCO, 0.000488 MHz - 2 MHz PDF資料下載
參數(shù)資料
| 型號(hào)： | LTC6990IS6#TRPBF |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | XO, clock |
| 英文描述： | VCO, 0.000488 MHz - 2 MHz |
| 封裝： | LEAD FREE, PLASTIC, TSOT-23, 6 PIN |
| 文件頁數(shù)： | 9/28頁 |
| 文件大?。?/td> | 310K |
| 代理商： | LTC6990IS6#TRPBF |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁當(dāng)前第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁
LTC6990
17
6990f
Figure 12. VCO Transfer Function
VCTRL (V)
1
f OUT
(kHz)
100
80
40
20
60
0
2
6990 F12
4
3
APPLICATIONS INFORMATION
The accuracy of KVCO does depend on VSET because the
output frequency is controlled by the ratio of VCTRL to
VSET. The frequency error (in Hertz) due to ΔVSET is ap-
proximated by:
ΔfOUT KVCO VCTRL
ΔVSET
VSET
As the equation indicates, the potential for error in output
frequency due to VSET error increases with KVCO and is
at its largest when VCTRL is at its maximum. Recall that
when VCTRL is at its maximum, the output frequency is at
its minimum. With the maximum absolute frequency error
(in Hertz) occurring at the lowest output frequency, the
relative frequency error (in percent) can be signicant.
VSET is nominally 1.0V with a maximum error of ±30mV
for at most a ±3% error term. However, this ±3% potential
error term is multiplied by both VCTRL and KVCO. Wide fre-
quency range applications (high KVCO) can have frequency
errors greater than ±50% at the highest VCTRL voltage
(lowest fOUT). For this reason the simple, two resistor VCO
circuit must be used with caution for applications where
the frequency range is greater than 4:1. Restricting the
range to 4:1 typically keeps the frequency error due to
VSET variation below 10%.
For wide frequency range applications, the non-inverting
VCO circuit shown in Figure 13 is preferred because the
maximum frequency error occurs when the frequency
is highest, keeping the relative error (in percent) much
smaller.
Example: Design a VCO with the Following Parameters
fOUT(MAX) = 100kHz at VCTRL(MIN) = 1V
fOUT(MIN) = 10kHz at VCTRL(MAX) = 4V
Step 1: Select the NDIV Value
First, choose an NDIV that meets the requirements of
Equation (3a).
6.25 ≤ NDIV ≤ 10
The application’s desired frequency range is 10:1, which
isn’t always possible. However, in this case NDIV = 8 meets
both requirements of Equation (3).
Step 2: Calculate KVCO and f(0V)
Next, calculate the intermediate values KVCO and f(0V) using
Equations (3b) and (3c).
KVCO =
100kHz 10kHz
4V 1V
= 30kHz/V
f(0V) =100kHz + 30kHz/V 1V =130kHz
Step 3: Calculate and Select RVCO
The next step is to use Equation (3d) to calculate the cor-
rect value for RVCO.
RVCO =
1MHz 50k
81V 30kHz/V
= 208.333k
Select RVCO = 210k.
Step 4: Calculate and Select RSET
The nal step is to calculate the correct value for RSET
using Equation (3e).
RSET =
1MHz 50k
8 130kHz 1V 30kHz/V
(
)
= 62.5k
Select RSET = 61.9k
In this design example, with its wide 10:1 frequency range,
the potential output frequency error due to VSET error alone
ranges from less than ±1% when VCTRL is at its minimum
up to ±36% when VCTRL is at its maximum. This error
must be accounted for in the system design.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTP-537HR | |
| LTS-313AG | |
| LTS-313AY | |
| LTS-360G | |
| LTS-4910AHR | |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC6990MPS6#PBF | 制造商:Linear Technology 功能描述:SC-Timing, Cut Tape VCO with Confirgurable Gain and Voltage Range, MP |
| LTC6990MPS6#TRMPBF | 功能描述:IC VCO CONFIG GAIN/VOLT TSOT23-6 RoHS:是 類別:集成電路 (IC) >> 時(shí)鐘/計(jì)時(shí) - 可編程計(jì)時(shí)器和振蕩器 系列:TimerBlox® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:45 系列:- 類型:溫度 - 補(bǔ)償晶體振蕩器（TCXO） 計(jì)數(shù):- 頻率:25MHz 電源電壓:3.135 V ~ 3.465 V 電流 - 電源:1.5mA 工作溫度:-40°C ~ 85°C 封裝/外殼:16-SOIC（0.295"，7.50mm 寬） 包裝:管件 供應(yīng)商設(shè)備封裝:16-SOIC W 安裝類型:表面貼裝 |
| LTC6990MPS6#TRPBF | 功能描述:IC VCO CONFIG GAIN/VOLT TSOT23-6 RoHS:是 類別:集成電路 (IC) >> 時(shí)鐘/計(jì)時(shí) - 可編程計(jì)時(shí)器和振蕩器 系列:TimerBlox® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:45 系列:- 類型:溫度 - 補(bǔ)償晶體振蕩器（TCXO） 計(jì)數(shù):- 頻率:25MHz 電源電壓:3.135 V ~ 3.465 V 電流 - 電源:1.5mA 工作溫度:-40°C ~ 85°C 封裝/外殼:16-SOIC（0.295"，7.50mm 寬） 包裝:管件 供應(yīng)商設(shè)備封裝:16-SOIC W 安裝類型:表面貼裝 |
| LTC6991 | 制造商:LINER 制造商全稱:Linear Technology 功能描述:TimerBlox: Resettable, Low Frequency Oscillator |
| LTC6991CDCB#TRMPBF | 功能描述:IC OSC SILICON 977HZ 6-DFN RoHS:是 類別:集成電路 (IC) >> 時(shí)鐘/計(jì)時(shí) - 可編程計(jì)時(shí)器和振蕩器 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:3,000 系列:- 類型:振蕩器 - 晶體 計(jì)數(shù):- 頻率:- 電源電壓:2.3 V ~ 5.5 V 電流 - 電源:1.07mA 工作溫度:-30°C ~ 80°C 封裝/外殼:SOT-665 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:SS迷你型-5D 安裝類型:表面貼裝 其它名稱:AN8955SSMTXLTR |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。