For more information www.linear.com/LTC6990 APPLICATIONS INFORMATION Start-Up Behavio" />
參數(shù)資料
型號： DC1562A-A
廠商： Linear Technology
文件頁數(shù)： 7/30頁
文件大?。?/td> 0K
描述： BOARD EVAL LTC6990
設(shè)計資源： DC1562A Design Files
DC1562A Schematic
特色產(chǎn)品： TimerBlox?
標(biāo)準(zhǔn)包裝： 1
系列： TimerBlox®
主要目的： 計時，電壓控制振蕩器（VCO）
嵌入式： 否
已用 IC / 零件： LTC6990
主要屬性： 1kHz ~ 10kHz 頻率范圍
次要屬性： 2.25 V ~ 5.5 V 電源
已供物品： 板
相關(guān)產(chǎn)品： LTC6990MPS6#TRPBF-ND - IC VCO CONFIG GAIN/VOLT TSOT23-6
LTC6990MPS6#TRMPBF-ND - IC VCO CONFIG GAIN/VOLT TSOT23-6
LTC6990IS6#TRMPBFDKR-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990HS6#TRMPBFDKR-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990IS6#TRMPBFCT-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990HS6#TRMPBFCT-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990IS6#TRPBF-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990IS6#TRMPBFTR-ND - IC OSC SILICON 1MHZ TSOT23-6
LTC6990IDCB#TRPBF-ND - IC OSC SILICON 1MHZ 6DFN
LTC6990IDCB#TRMPBF-ND - IC OSC SILICON 1MHZ 6DFN
更多...
LTC6990
15
6990fc
For more information www.linear.com/LTC6990
APPLICATIONS INFORMATION
Start-Up Behavior
When first powered up, the output is high impedance. If
the output is enabled (OE = 1) at the end of the start-up
time, the output will go low for one tMASTER cycle (or half
a tOUT cycle if NDIV < 4) before the first rising edge. If the
output is disabled (OE = 0) at the end of the start-up time,
the output will drop to a low output if the Hi-Z bit = 0, or
simply remain floating if Hi-Z = 1.
Basic Fixed Frequency Operation
The simplest and most accurate method to program the
LTC6990 for fixed frequency operation is to use a single
resistor, RSET, between the SET and GND pins. The design
procedureisasimpletwostepprocess.FirstselecttheNDIV
value and then calculate the value for the RSET resistor.
Alternatively, Linear Technology offers the easy to use
TimerBlox Designer tool to quickly design any LTC6990
based circuit. Download the free TimerBlox Designer
software at www.linear.com/timerblox.
Step 1: Selecting the NDIV Frequency Divider Value
As explained earlier, the voltage on the DIV pin sets the
DIVCODE which determines both the Hi-Z bit and the
NDIV value. For a given output frequency, NDIV should be
selected to be within the following range.
62.5kHz
fOUT
≤ NDIV ≤
1MHz
fOUT
(1a)
To minimize supply current, choose the lowest NDIV value
(generallyrecommended).Forfasterstart-upordecreased
jitter,chooseahigherNDIVsetting.Alternatively,useTable1
as a guide to select the best NDIV value for the given ap-
plication. After choosing the value for NDIV, use Table 1 to
select the proper resistor divider or VDIV/V+ ratio to apply
to the DIV pin.
Step 2: Calculate and Select RSET
The final step is to calculate the correct value for RSET
using the following equation.
RSET =
1MHz 50k
NDIV fOUT
(1b)
Select the standard resistor value closest to the calculated
value.
Example: Design a 20kHz Oscillator with Minimum
Power Consumption
Step 1: Selecting the NDIV Frequency Divider Value
First, choose an NDIV value that meets the requirements
of Equation (1a).
3.125 ≤ NDIV ≤ 50
Potential settings for NDIVinclude4,8,16,and32.NDIV=4
is the best choice, as it minimizes supply current by using
a large RSET resistor. Using Table 1, choose the R1 and R2
values to program DIVCODE to either 2 or 13, depending
on the desired behavior when the output is disabled.
Step 2: Select RSET
Calculate the correct value for RSET using Equation (1b).
RSET =
1MHz 50k
4 20kHz
= 625k
Since 625k is not available as a standard 1% resistor,
substitute 619k if a 0.97% frequency shift is acceptable.
Otherwise, select a parallel or series pair of resistors such
as 309k and 316k to attain a more precise resistance.
相關(guān)PDF資料
PDF描述
HCM11DRAH CONN EDGECARD 22POS R/A .156 SLD
ECE-P2DP562HA CAP ALUM 5600UF 200V 20% SNAP
HBM24DSUS CONN EDGECARD 48POS .156 DIP SLD
ECE-P2DA472HX CAP ALUM 4700UF 200V 20% SNAP
RBM24DCWN CONN EDGECARD 48POS DIP .156 SLD
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DC1562A-B 功能描述:BOARD EVAL LTC6991 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估演示板和套件 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:電信，線路接口單元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板，電源，線纜，CD 其它名稱:82EBV2081
DC1562A-C 功能描述:BOARD EVAL LTC6992-1 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估演示板和套件 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:數(shù)字電位器 嵌入式:- 已用 IC / 零件:AD5258 主要屬性:- 次要屬性:- 已供物品:板 相關(guān)產(chǎn)品:AD5258BRMZ1-ND - IC POT DGTL I2C1K 64P 10MSOPAD5258BRMZ10-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ100-ND - IC POT DGTL I2C 100K 64P 10MSOPAD5258BRMZ50-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ1-R7-ND - IC POT DGTL I2C 1K 64P 10MSOPAD5258BRMZ10-R7-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ50-R7-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ100-R7-ND - IC POT DGTL I2C 100K 64P 10MSOP
DC1562A-D 功能描述:BOARD EVAL LTC6992-2 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估演示板和套件 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:數(shù)字電位器 嵌入式:- 已用 IC / 零件:AD5258 主要屬性:- 次要屬性:- 已供物品:板 相關(guān)產(chǎn)品:AD5258BRMZ1-ND - IC POT DGTL I2C1K 64P 10MSOPAD5258BRMZ10-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ100-ND - IC POT DGTL I2C 100K 64P 10MSOPAD5258BRMZ50-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ1-R7-ND - IC POT DGTL I2C 1K 64P 10MSOPAD5258BRMZ10-R7-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ50-R7-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ100-R7-ND - IC POT DGTL I2C 100K 64P 10MSOP
DC1562A-E 功能描述:BOARD EVAL LTC6992-3 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估演示板和套件 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:數(shù)字電位器 嵌入式:- 已用 IC / 零件:AD5258 主要屬性:- 次要屬性:- 已供物品:板 相關(guān)產(chǎn)品:AD5258BRMZ1-ND - IC POT DGTL I2C1K 64P 10MSOPAD5258BRMZ10-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ100-ND - IC POT DGTL I2C 100K 64P 10MSOPAD5258BRMZ50-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ1-R7-ND - IC POT DGTL I2C 1K 64P 10MSOPAD5258BRMZ10-R7-ND - IC POT DGTL I2C 10K 64P 10MSOPAD5258BRMZ50-R7-ND - IC POT DGTL I2C 50K 64P 10MSOPAD5258BRMZ100-R7-ND - IC POT DGTL I2C 100K 64P 10MSOP
DC1562A-F 功能描述:BOARD EVAL LTC6992-4 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估演示板和套件 系列:TimerBlox® 標(biāo)準(zhǔn)包裝:1 系列:- 主要目的:電信，線路接口單元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要屬性:T1/J1/E1 LIU 次要屬性:- 已供物品:板，電源，線纜，CD 其它名稱:82EBV2081
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*