Datasheet > AN49.0

AN49.0

更新时间： 2024-11-13 22:05:43

品牌	Logo	应用领域
英特矽尔 - INTERSIL		音频放大器
页数	文件大小	规格书
2页	156K
描述
Digital Audio Amplifier Gain Control using Logarithmic

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

AN49.0 数据手册

Digital Audio Amplifier Gain Control using Logarithmic

Intersil Digitally Controlled Potentiontiometers (XDCPs)

Application Note

April 21, 2005

AN49.0

Author: Applications Staff

Often the power amplifier stage of a communications device

is located some distance from the control panel. The typical

solution is to mount the volume control on the front panel

and run a pair of shielded cables back to the power amplifier

stage. A better solution is to use the Intersil X9314

logarithmic taper digitally controlled potentiometer. This

completely eliminates the need for shielded cables since the

digital pot can be located on the printed circuit board near

the low level input stages of the power amplifier. The

up/down volume switches can be located yards away as

these are merely low speed TTL signals.

The frequency of the oscillation (and consequently the

speed at which the volume can be controlled) is determined

by C1 and R1. The values shown will advance the X9314

through all 32 wiper taps in about 5 seconds. R1 can be

changed from 5KW to 1MW to suit your preference. When

the pushbutton switches are released, R2 and C2 delay the

release of the X9314 chip select in order to ensure that the

last increment pulse is written.

The X9314W needs little else to apply it to most audio

circuits, but C9 has been included here to remove any DC

component that may be present on the input signal. Also,

lowpass filter R7 and C8 removes residual high frequency

noise from the digital pots’ internal charge pumps.

Circuit Description

Figure 1 shows the X9314 with the low voltage LM386 power

amplifier. This circuit will produce 250mW of audio power

with only a 5V DC source. Figure 2 is a similar circuit that

uses the higher power LM380 and is capable of delivering

over 1W of audio if a 12V DC source is available. Either

circuit will provide plenty of sound for intercom,

The LM380 and LM386 power amplifiers have fixed gains of

34dB and 26dB respectively. The gain of the LM386 can be

increased to 46dB (X200) by connecting a 10µF capacitor

from pins 1 to 8. The positive pole of the capacitor should be

connected to pin 1. The output snubber network (R6 and C5)

is required for stability and should be located close to the

output pin of the power amplifier. These amplifiers have fairly

high gain and wide bandwidths, so be careful with PCB trace

lengths. All connections to these amplifiers should be as

short and direct as possible.

communications, or monitoring applications. The 1W circuit

would be preferred when higher ambient noise is present,

such as in an automobile.

A 74HC132 quad Schmitt nand gate (U2) plus a few

discretes are all that are required to interface to U1, the

X9314W 10kΩ XDCP. When either pushbutton switch, S1 or

S2, is depressed, U2A output will be HIGH. This immediately

brings U2B output LOW which enables the XDCP. After a

short delay determined by R3 and C3, the astable

multivibrator (U2C) will begin generating increment pulses.

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-352-6832 | Intersil (and design) is a registered trademark of Intersil Americas Inc.

All other trademarks mentioned are the property of their respective owners.

中文翻译

下载PDF

与AN49.0相关器件

型号	品牌	获取价格	描述	数据表
AN4999	ETC	获取价格	Turn-on of thyristors in parallel
AN4X	ABRACON	获取价格	ANNICHE 5G
AN5001	ETC	获取价格	Use of the VTO. rT on-state characteristic model
AN-5001	FAIRCHILD	获取价格	LVX Low Voltage Dual Supply CMOS Translating Transceivers
AN-5002	FAIRCHILD	获取价格	GTLP: Single vs. Multiple Output Switching Technical Discussion
AN501	VISHAY	获取价格	The DG535/536 Wideband Multiplexers Suit a Wide Variety of Applications
AN-501(FC67211)	ETC	获取价格	UEBERSTROMSCHUTZSCHALTER MINIATUR 5A
AN5010	ETC	获取价格	TV ELECTRONIC CHANNEL SELECTION CIRCUIT
AN5011	ETC	获取价格	TV Channel Selector Circuit
AN5013K	ETC	获取价格	TV Channel Selector Circuit

与AN49.0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

5
英伟达新一代Blackwell GPU过热问题致交付延迟
2024-11-18

2
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

29
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

12

产品中心

服务支持

精选活动

关于我们

帮助中心

AN49.0

AN49.0 数据手册

与AN49.0相关器件

与AN49.0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

AN49.0

AN49.0 数据手册

与AN49.0相关器件

与AN49.0相关文章

您还可以找

您在本页遇到什么问题？