- 您现在的位置：买卖IC网 > PDF目录2092 > MAX9875ERP+T (Maxim Integrated Products)IC AUDIO SUBSYSTEM 20UCSP PDF资料下载
参数资料
| 型号： | MAX9875ERP+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 11/30页 |
| 文件大小： | 0K |
| 描述： | IC AUDIO SUBSYSTEM 20UCSP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 系列： | DirectDrive® |
| 类型： | D 类 |
| 输出类型： | 1-通道（单声道），带立体声耳机 |
| 在某负载时最大输出功率 x 通道数量： | 825mW x 1 @ 4 欧姆; 53mW x 2 @ 16 欧姆 |
| 电源电压： | 2.7 V ~ 5.25 V |
| 特点： | 消除爆音，差分输入，I²C，静音，短路和热保护，关机，音量控制 |
| 安装类型： | 表面贴装 |
| 供应商设备封装： | 20-UCSP |
| 封装/外壳： | 20-WFBGA，CSPBGA |
| 包装： | 带卷 (TR) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页当前第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页
MAX9875
Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier
______________________________________________________________________________________
19
1) The sleeve is typically grounded to the chassis.
Using the midrail biasing approach, the sleeve must
be isolated from system ground, complicating prod-
uct design.
2) During an ESD strike, the amplifier’s ESD structures
are the only path to system ground. Thus, the ampli-
fier must be able to withstand the full energy from an
ESD strike.
3) When using the headphone jack as a line out to
other equipment, the bias voltage on the sleeve may
conflict with the ground potential from other equip-
ment, resulting in possible damage to the amplifiers.
The MAX9875 features a low-noise charge pump. The
switching frequency of the charge pump is 1/2 of the
Class D switching frequency, regardless of the operating
mode. When the Class D amplifiers are operated in
spread-spectrum mode, the charge pump also switches
with a spread-spectrum pattern. The nominal switching
frequency is well beyond the audio range, and thus does
not interfere with audio signals. The switch drivers fea-
ture a controlled switching speed that minimizes noise
generated by turn-on and turn-off transients. By limiting
the switching speed of the charge pump, the di/dt noise
caused by the parasitic trace inductance is minimized.
Although not typically required, additional high-frequen-
cy noise attenuation can be achieved by increasing the
size of C2 (see the
Typical Application Circuit). The
charge pump is active only in headphone modes.
Headphone Current Limit
The headphone amplifier current is limited to 140mA (typ).
The current limit clamps the output current, which appears
as clipping when the maximum current is exceeded.
Shutdown Mode
The MAX9875 features two ways of entering low-power
shutdown. The hardware shutdown function is controlled
by pulsing BIAS low for 1ms. While BIAS is low the ampli-
fiers are shut down. Following an 80ms reset period, the
MAX9875 reverts to its power-on-reset condition. Pull
BIAS low using an open-drain output that is not pulled up
with a resistor (see the
Typical Application Circuit). The
open-drain output leakage must not exceed 100nA and
must be able to sink at least 1mA.
The device can also be placed in shutdown mode by
writing to the SHDN bit in the Output Mode Control
Register.
Click-and-Pop Suppression
The MAX9875 features click-and-pop suppression that
eliminates audible transients from occurring at startup
and shutdown.
Use the following procedure to start up the MAX9875:
1) Configure the desired output mode and preamplifier gain.
2) Set the SHDN bit to 1 to start up the amplifier.
3) Wait 10ms for the startup time to pass.
4) Increase the output volume to the desired level.
To disable the device simply set SHDN to 0.
During the startup period, the MAX9875 precharges the
input capacitors to prevent clicks and pops. If the output
amplifiers have been programmed to be active they are
held in shutdown until the precharge period is complete.
When power is initially applied to the MAX9875, the
power-on-reset state of all three volume control registers
is mute. For most applications, the volume can be set to
the desired level once the device is active. If the click-
and-pop is too high, step through intermediate volume
settings with zero-crossing detection disabled. Stepping
through higher volume settings has a greater impact on
click-and-pop than lower volume settings.
For the lowest possible click-and-pop, start up the device
at minimum volume and then step through each volume
setting until the desired setting is reached. Disable zero-
crossing detection if no input signal is expected.
VDD
VDD/2
GND
CONVENTIONAL AMPLIFIER BIASING SCHEME
DirectDrive AMPLIFIER BIASING SCHEME
+VDD
GND
-VDD
(VSS)
Figure 5. Traditional Amplifier Output vs. MAX9875 DirectDrive
Output
相关PDF资料 |
PDF描述 |
|---|---|
| MAX9877AERP+T | IC SUBSYSTEM MONO AUD 20MAXFILM |
| MAX9877EWP+TG45 | IC AUDIO SUBSYSTEM 20-WLP |
| MAX9879ERV+T | IC AUDIO SUBSYSTEM 30-UCSP |
| MAX987EUK-T | IC COMP MICRPWR R-R I/O SOT23-5 |
| MAX9888EWY+T | IC CODEC AUDIO FLEXSOUND 63WLP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX9877AERP+T | 功能描述:音频放大器 Audio Subsystem w/DirectDrive 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 |
| MAX9877AEWP+G45 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX9877AEWP+TG45 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX9877EBP+G45 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX9877EBP+TG45 | 制造商:Maxim Integrated Products 功能描述: |
发布紧急采购，3分钟左右您将得到回复。