Datasheet > APN1005

APN1005

更新时间： 2024-11-21 08:33:07

品牌	Logo	应用领域
思佳讯 - SKYWORKS		电视
页数	文件大小	规格书
11页	266K
描述
A Balanced Wideband VCO for Set-Top TV Tuner Applications

阅读下载

中文翻译

获取价格

数据手册

如果您发现信息不准确，欢迎纠错

APN1005 数据手册

APPLICATION NOTE

APN1005: A Balanced Wideband VCO

for Set-Top TV Tuner Applications

Introduction

VCO Model

Modern set-top TV DBS tuner systems require more channel

coverage, while maintaining competitive prices. This situation

creates tough design goals: to improve performance and simplify

design.

Figure 1 shows the VCO model built for open loop analysis in Libra

Series IV including the SMV1265-011 varactor model.

The circuit schematic in Figure 2 shows a pair of transistors in a

single feedback loop, connected so that collector currents would

be 180° shifted (ideally). A pair of back-to-back connected

SMV1265-011 varactors is used, rather than a single one. This

allows lower capacitance at the high-voltage range, without

changing the tuning ratio. The reason is that, apart from package

capacitance, certain mounting fringing capacitances, though

small, may strongly affect higher frequency margins. The effects

Balanced VCO configuration could be a competitive circuit

solution, since it provides the widest tuning range with practical

circuitry and layout. However, tuning margins would be further

improved by optimizing the varactor manufacturing process.

Skyworks has developed such a process to satisfy the most

ambitious wideband design goals.

of parasitic capacitances were summarized in the model as C

In this publication, we will address the design of the balanced-

type voltage control oscillator (VCO) based on the newly

developed varactor SMV1265-011 with the unique set of

capacitance tuning ratios and Q-quality.

and C , valued 0.4 pF each. These values may vary depending on

the layout of the board. Varactor DC biasing is provided through

resistors R and R , both 1 k, which may affect the phase noise,

but eliminate the need for inductive chokes. This minimizes

overall costs and the possibility of parasitic resonances — the

usual cause for frequency instability and spurs.

The phase corrector DC chokes, SRL and SRL , were modeled

as lossless inductors at 33 nH since their losses are dominated

by the 30 Ω emitter biasing resistors. DC blocking series capaci-

tances (C

and C ) are modeled as an SRC network,

SER2

SER1

including associated parasitics. Their values were optimized to

10 pF providing smooth tuning over the design band.

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

200314 Rev. A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 21, 2005

12 3 4 5 6 7...11

中文翻译

下载PDF

与APN1005相关器件

型号	品牌	获取价格	描述	数据表
APN1006	SKYWORKS	获取价格	A Colpitts VCO for Wideband (0.95–2.15 GHz) S
APN6	ETC	获取价格	Analog IC
APNA160ARA101MF70G	CHEMI-CON	获取价格	The Super long life of 12,000 hours at 125°C
APNA2R5ARA561MF70G	CHEMI-CON	获取价格	The Super long life of 12,000 hours at 125°C
APNA6R3ARA331MF70G	CHEMI-CON	获取价格	The Super long life of 12,000 hours at 125°C
APNAPA2BC	AMPHENOL	获取价格	Circular Connector, 2 Contact(s), Male, Receptacle
APNAPA2BR	AMPHENOL	获取价格	Circular Connector, 2 Contact(s), Male, Receptacle
APNAPA2NC	AMPHENOL	获取价格	Circular Connector, 2 Contact(s), Male, Receptacle
APNAPA2NR	AMPHENOL	获取价格	Circular Connector, 2 Contact(s), Male, Receptacle
APNAPA6BC	AMPHENOL	获取价格	Circular Connector, 2 Contact(s), Male, Clamp Terminal, Plug

与APN1005相关文章

解析光耦仿真器：升级光耦合器技术的必要性
2024-11-18

31
英伟达新一代Blackwell GPU过热问题致交付延迟
2024-11-18

22
国产厂商思特威CMOS图像传感器芯片单月出货超1亿颗，技术创新引领行业发展
2024-11-14

51
台积电5nm和3nm产能利用率达100%，半导体行业景气度持续攀升
2024-11-14

50

产品中心

服务支持

精选活动

关于我们

帮助中心

APN1005

APN1005 数据手册

与APN1005相关器件

与APN1005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

APN1005

APN1005 数据手册

与APN1005相关器件

与APN1005相关文章

您还可以找

您在本页遇到什么问题？