参数资料
型号: TDF8553J
厂商: NXP SEMICONDUCTORS
元件分类: 音频/视频放大
英文描述: 87 W, 4 CHANNEL, AUDIO AMPLIFIER, PZFM37
封装: PLASTIC, SOT725-1
文件页数: 3/47页
文件大小: 391K
代理商: TDF8553J
TDF8553J_1
NXP B.V. 2008. All rights reserved.
Objective data sheet
Rev. 01 — 3 December 2008
11 of 47
NXP Semiconductors
TDF8553J
4
× 50 Watt power amplier and multiple voltage regulator
8.5.7.3
Load detection procedure
1. At start-up, enable the AC or DC-load detection by setting D1 of instruction byte IB1 to
logic 1.
2. After 250 ms the DC load is detected and the mute is released. This is inaudible and
can be implemented each time the IC is powered on.
3. When the amplier start-up cycle is completed (after 1.5 s), apply an AC signal to the
input, and DC-load bits D5 of each data byte should be read and stored by the
microcontroller.
4. After at least 3 periods of the input signal, the load status can be checked by reading
AC-detect bits D4 of each data byte.
The AC-load peak current counter can be reset by setting bit D1 of instruction
byte IB1 to logic 0 and then to logic 1. Note that this will also reset the DC-load
detection bits D5 in each data byte.
8.5.8 Low headroom protection
The normal DC output voltage of the amplier is set to half the supply voltage and is
related to the voltage on pin SVR. An external capacitor is connected to pin SVR to
suppress power supply ripple. If the supply voltage drops (at vehicle engine start), the DC
output voltage will follow slowly due to the affect of the SVR capacitor.
The headroom voltage is the voltage required for correct operation of the amplier and is
dened as the voltage difference between the level of the DC output voltage before the VP
voltage drop and the level of VP after the voltage drop (see Figure 4).
At a certain supply voltage drop, the headroom voltage will be insufcient for correct
operation of the amplier. To prevent unwanted audible noises at the output, the
headroom protection mode will be activated (see Figure 4). This protection discharges the
capacitors connected to pins SVR and ACGND to increase the headroom voltage.
(1) IoM = < 150 mA.
(2) IoM = > 550 mA.
Fig 3.
Tolerance of AC-load detection as a function of output voltage
001aai691
10
102
ZL
(
)
1
VoM (V)
010
7.5
2.5
5
(2)
(1)
no load present
load present
undefined
相关PDF资料
PDF描述
TDF8554J/N2 44 W, 4 CHANNEL, AUDIO AMPLIFIER, PZFM37
TDF8554J/N4 44 W, 4 CHANNEL, AUDIO AMPLIFIER, PZFM37
TDF8555J/N1 44 W, 4 CHANNEL, AUDIO AMPLIFIER, PZFM37
TDF8599TD 70 W, 2 CHANNEL, AUDIO AMPLIFIER, PDSO36
TDF8599TH 70 W, 2 CHANNEL, AUDIO AMPLIFIER, PDSO36
相关代理商/技术参数
参数描述
TDF8590TH 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:2 X 80 W SE (4 OHM) or 1 X 160 W BTL (8 OHM) class-D amplifier
TDF8590TH/N1,118 功能描述:音频放大器 AMPLIFIER CLASS D RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel
TDF8590TH/N1S,118 功能描述:音频放大器 4/8 OHM CLASS D AMP RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel
TDF8590TH/N1-T 功能描述:音频放大器 AMPLIFIER CLASS D RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel
TDF8590TH/N1TJ 制造商:NXP Semiconductors 功能描述:- Tape and Reel