Datasheet > DS1087LU-450+T

DS1087LU-450+T

更新时间： 2024-02-12 13:16:04

品牌	Logo	应用领域
美信 - MAXIM		/
页数	文件大小	规格书
12页	150K
描述
Analog Circuit

阅读下载

中文翻译

获取价格

技术参数
数据手册

如果您发现信息不准确，欢迎纠错

DS1087LU-450+T 技术参数

是否Rohs认证：	符合	生命周期：	Active
包装说明：	,	Reach Compliance Code：	compliant
HTS代码：	8542.39.00.01	风险等级：	5.58
模拟集成电路 - 其他类型：	ANALOG CIRCUIT	峰值回流温度（摄氏度）：	NOT SPECIFIED
处于峰值回流温度下的最长时间：	NOT SPECIFIED	Base Number Matches：	1

DS1087LU-450+T 数据手册

3.3V Spread-Spectrum EconOscillator

Table 1. Register Summary

ADDR

BINARY

FACTORY DEFAULT

ACCESS

LO/

HIZ

PRESCALER

02h

110- - - - - b

R/W

ADDR

0Dh

3Fh

11110000b

—

R/W

—

WRITE EE

No Data

X = Don’t care; read as one.

programmed frequency. Although the output frequency

changes when the dither is enabled, the duty cycle

does not change.

Detailed Description

A block diagram of the DS1087L is shown in Figure 1.

Output Frequency

The internal master oscillator can generate a square

wave with a frequency range of 33.3MHz to 66.6MHz.

The master oscillator frequency and output frequency

are factory programmed, although the user can use the

programmable divider to divide the master oscillator

frequency by 2^x(where x equals 0 to 8).

The dither is controlled by the J0 bit in the PRESCALER

spectral attenuation occurs when the prescaler is set to

1. The spectral attenuation is reduced by 2.7dB for

every factor of 2 that is used in the prescaler. This hap-

pens because the prescaler’s divider function tends to

average the dither in creating the lower frequency.

However, the most stringent spectral emission limits are

imposed on the higher frequencies where the prescaler

is set to a low divider ratio.

Output Control and Power-Down

Two user control signals control the output. The output-

enable pin, OE, gates the clock output buffer and the

PDN pin disables the master oscillator and turns off the

output for power-sensitive applications (note: the

power-down command must persist for at least two out-

put frequency cycles plus 10µs for deglitching purpos-

es). On power-up, the output is disabled until power is

stable and the master oscillator has generated 512

clock cycles.

A triangle-wave generator injects an offset element into

the master oscillator to dither its output. The dither rate

(see Equation 1) is based on the master oscillator fre-

quency. Figure 2 shows a plot of the output frequency

versus dither rate.

(1)

DitherRate =

Both controls feature a synchronous enable, which

ensures there are no output glitches when the output is

enabled. The synchronous enable also ensures a con-

stant time interval (for a given frequency setting) from

an enable signal to the first output transition.

4096

where f = master oscillator frequency

The DS1087L registers are used to change the dither

amount, output frequency, and slave address. A sum-

mary of the registers is shown in Table 1. Once pro-

grammed into EEPROM, the settings only need to be

reprogrammed if it is desired to reconfigure the device.

Spread Spectrum

The DS1087L can reduce radiated emission peaks. The

output frequency can be dithered 2% or 4% below the

OUTPUT FREQUENCY

PRESCALER Register

Bit 5:

Output Low or High-Z. The LO/HIZ bit

controls the output. During power-down,

while the output is deactivated, if the

LO/HIZ bit is set to 0, the output is high-Z.

If the LO/HIZ bit is set to 1, the output is

driven low.

f /N

(f /N) - 4%

DITHER RATE

2f /4096

f /4096

Bit 4:

Dither Control. The J0 bit controls the

dither applied to the output. When J0 is

high, 2% peak dither is selected. When

J0 is low, 4% peak dither is selected.

WHERE N = (2^X)

= FACTORY PROGRAMMED MASTER OSCILLATOR FREQUENCY

Figure 2. Output Frequency vs. Dither Rate

_____________________________________________________________________

1...5 6 789 10 11 12

中文翻译

下载PDF

与DS1087LU-450+T相关器件

型号	品牌	获取价格	描述	数据表
DS1087LU-466	MAXIM	获取价格	3.3V Spread-Spectrum EconOscillator
DS1087LU-466	DALLAS	获取价格	3.3V Spread-Spectrum EconOscillator
DS1087LU-YXX	MAXIM	获取价格	3.3V Spread-Spectrum EconOscillator
DS1088	ADI	获取价格	低成本、固定频率EconOscillator?
DS1088C	MAXIM	获取价格	Fixed-Frequency EconoOscillator?
DS1088C_V01	MAXIM	获取价格	Fixed-Frequency EconOscillatorâ¢
DS1088CN-133 T	MAXIM	获取价格	Fixed-Frequency EconoOscillator?
DS1088CN-133+T	MAXIM	获取价格	Fixed-Frequency EconoOscillatorâ¢
DS1088CX-133 T	MAXIM	获取价格	Fixed-Frequency EconoOscillator?
DS1088CX-133+T	MAXIM	获取价格	Fixed-Frequency EconoOscillatorâ¢

与DS1087LU-450+T相关文章

LM317T数据手册解读：产品特性、应用、封装与引脚详解
2024-06-14

11
一文带你了解?DB3二极管好坏判断、参数信息、替代推荐
2024-06-14

14
LM358DR数据手册：引脚说明、电气参数及替换型号推荐
2024-06-14

8
OP07CP数据手册解读：引脚信息、电子参数
2024-06-14

8

产品中心

服务支持

精选活动

关于我们

帮助中心

DS1087LU-450+T

DS1087LU-450+T 技术参数

DS1087LU-450+T 数据手册

与DS1087LU-450+T相关器件

与DS1087LU-450+T相关文章

您还可以找

产品中心

服务支持

精选活动

关于我们

帮助中心

DS1087LU-450+T

DS1087LU-450+T 技术参数

DS1087LU-450+T 数据手册

与DS1087LU-450+T相关器件

与DS1087LU-450+T相关文章

您还可以找

您在本页遇到什么问题？