參數(shù)資料
型號(hào): LM4935
廠商: National Semiconductor Corporation
元件分類: ADC
英文描述: Audio Sub-System with Dual-Mode Stereo Headphone and Mono High Efficiency Loudspeaker Amplifiers and Multi-Purpose ADC
中文描述: 音頻子系統(tǒng)的雙模單聲道立體聲耳機(jī)和揚(yáng)聲器放大器的高效率和多功能模數(shù)轉(zhuǎn)換器
文件頁數(shù): 38/112頁
文件大小: 5017K
代理商: LM4935
12.0 Status & Control Registers
(Continued)
12.17 MIC_2 CONFIGURATION REGISTER
This register is used to control the microphone configuration.
TABLE 17. MIC_2 (0x0Ch)
Bits
0
Field
OCL_
VCM_
VOLTAGE
Description
Selects the voltage used as virtual ground (HP_VMID pin) in OCL mode. This will depend on the
available supply and the power output requirements of the headphone amplifiers.
OCL_VCM_VOLTAGE
0
1
Selects the voltage as a reference to the internal and external microphones. Only one bias pin is
driven at once depending on the INT_EXT bit setting found in the MIC_1 (0x0Bh) register.
MIC_BIAS_VOLTAGE should be set to ’11’ only if A_V
DD
>
3.4V. In OCL mode,
MIC_BIAS_VOLTAGE = ’00’ (EXT_BIAS = 2.0V) should not be used to generate the EXT_BIAS
supply for a cellular headset external microphone. Please refer to Table 18 for more detail.
MIC_BIAS_VOLTAGE
EXT_BIAS
00
2
2.0V
01
2
2.5V
10
2
2.8V
11
2
3.3V
If set the LM4935 assumes that the button (if used) in the headset is in series (series push button)
with the microphone, opening the circuit when pressed. The default is for the button to be in parallel
(parallel push button), shorting out the microphone when pressed.
Sets the time used for debouncing the pushing of the button on a headset with a parallel push
button.
BUTTON_DEBOUNCE_TIME
00
2
01
2
10
2
11
2
Voltage
1.2V
1.5V
2:1
MIC_
BIAS_
VOLTAGE
INT_BIAS
2.0V
2.5V
2.8V
3.3V
3
BUTTON_TYPE
5:4
BUTTON_
DEBOUNCE_
TIME
Time (ms)
0
8
16
32
In OCL mode there is a trade-off between the external microphone supply voltage (EXT_MIC_BIAS - OCL_VCM_ VOLTAGE) and
the maximum output power possible from the headphones. A lower OCL_VCM_VOLTAGE gives a higher microphone supply
voltage but a lower maximum output power from the headphone amplifiers due to the lower OCL_VCM_VOLTAGE - A_V
SS
.
TABLE 18. External MIC Supply Voltages in OCL Mode
Available
A_V
DD
>
3.4V
2.9V to 3.4V
2.8V to 2.9V
2.7V to 2.8V
Recommended
EXT_MIC_BIAS
Supply to Microphone
OCL_VCM_VOLT = 1.5V
1.8V
1.3V
1.0V
-
OCL_VCM_VOLT = 1.2V
2.1V
1.6V
1.3V
1.3V
3.3V
2.8V
2.5V
2.5V
L
www.national.com
38
相關(guān)PDF資料
PDF描述
LM4935WL Audio Sub-System with Dual-Mode Stereo Headphone and Mono High Efficiency Loudspeaker Amplifiers and Multi-Purpose ADC
LM4935WLX Audio Sub-System with Dual-Mode Stereo Headphone and Mono High Efficiency Loudspeaker Amplifiers and Multi-Purpose ADC
LM4936 Stereo 2W Audio Power Amplifiers with Volume Control and Selectable Control Interface (SPI or I2C)
LM4951 Wide Voltage Range 1.8 Watt Audio Amplifier
LM4953 Ground-Referenced, Ultra Low Noise, Ceramic Speaker Driver
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM49350 制造商:NSC 制造商全稱:National Semiconductor 功能描述:High Performance Audio Codec Sub-System with a Ground-Referenced Stereo Headphone Amplifier
LM49350RL 制造商:Texas Instruments 功能描述:Audio Codec 1ADC / 1DAC 36-Pin uSMD T/R 制造商:Texas Instruments 功能描述:AUDIO CODEC SUBSYSTEM 36MICRO SMDXT
LM49350RL/NOPB 功能描述:接口—CODEC Hi Perf Audio Codec Subsystem RoHS:否 制造商:Texas Instruments 類型: 分辨率: 轉(zhuǎn)換速率:48 kSPs 接口類型:I2C ADC 數(shù)量:2 DAC 數(shù)量:4 工作電源電壓:1.8 V, 2.1 V, 2.3 V to 5.5 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:DSBGA-81 封裝:Reel
LM49350RL/NOPB 制造商:Texas Instruments 功能描述:Audio Codec IC
LM49350RLEVAL 功能描述:音頻 IC 開發(fā)工具 LM49350RL EVAL BOARD RoHS:否 制造商:Texas Instruments 產(chǎn)品:Evaluation Kits 類型:Audio Amplifiers 工具用于評(píng)估:TAS5614L 工作電源電壓:12 V to 38 V