參數(shù)資料
型號(hào)： LM4548AVH/NOPB
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類： 消費(fèi)家電
英文描述： SPECIALTY CONSUMER CIRCUIT, PQFP48
封裝： 7 X 7 MM, 1.40 MM HEIGHT, LQFP-48
文件頁(yè)數(shù)： 16/28頁(yè)
文件大?。?/td> 538K
代理商： LM4548AVH/NOPB
Register Descriptions (Continued)
Record Gain Register (1Ch)
Mute
Gx3:Gx0
Function
0
1111
22.5dB gain
0
0000
0dB gain
1
XXXX
*mute
Default: 8000h
GENERAL PURPOSE REGISTER (20h)
This register controls many miscellaneous functions imple-
mented on the LM4548A. The miscellaneous control bits
include POP which allows the DAC output to bypass the
National 3D Sound circuitry, 3D which enables or disables
the National 3D Sound circuitry, MIX which selects the MO-
NO_OUT source, MS which controls the Microphone Selec-
tion mux and LPBK which connects the output of the stereo
ADC to the input of the stereo DAC. LPBK provides a
mixed-mode analog and digital loopback path between ana-
log inputs and analog outputs.
BIT
Function
POP
PCM Out Path:
*0 = 3D allowed
1 = 3D bypassed
3D
National 3D Sound:
*0 = off
1= on
MIX
Mono output select:
*0 = Mix
1 = Mic
MS
Mic select:
*0 = MIC1
1 = MIC2
LPBK
ADC/DAC Loopback:
*0 = No Loopback
1 = Loopback
Default: 0000h
3D CONTROL REGISTER (22h)
This read-only (0101h) register indicates, in accordance with
the AC ’97 Rev 2 Specification, the fixed depth and center
characteristics of the National 3D Sound stereo enhance-
ment.
BIT
Function
POP
PCM Out Path:
*0 = 3D allowed
1 = 3D bypassed
3D
National 3D Sound:
*0 = off
1= on
MIX
Mono output select:
*0 = Mix
1 = Mic
MS
Mic select:
*0 = MIC1
1 = MIC2
LPBK
ADC/DAC Loopback:
*0 = No Loopback
1 = Loopback
Default: 0000h
POWERDOWN CONTROL / STATUS REGISTER (26h)
This read/write register is used both to monitor subsystem
readiness and also to program the LM4548A powerdown
states. The 4 LSBs indicate status and 6 of the 8 MSBs
control powerdown.
The 4 LSBs of this register indicate the status of the 4 audio
subsections of the codec: Reference voltage, Analog mixers
and amplifiers, DAC section, ADC section. When the "Codec
Ready" indicator bit in the AC Link Input Frame (SDATA_IN:
slot 0, bit 15) is a "1", it indicates that the AC Link and AC ’97
registers are in a fully operational state and that control and
status information can be transferred. It does not indicate
that the codec is ready to send or receive audio PCM data or
to pass signals through the analog I/O and mixers. To deter-
mine that readiness, the Controller must check that the 4
LSBs of this register are set to “1” indicating that the appro-
priate audio subsections are ready.
The powerdown bits PR0 – PR5 control internal subsections
of the codec. They are implemented in compliance with AC
’97 Rev 2 to support the standard device power manage-
ment states D0 – D3 as defined in the ACPI and PCI Bus
Power Management specification.
PR0 controls the powerdown state of the ADC and associ-
ated sampling rate conversion circuitry. PR1 controls power-
down for the DAC and the DAC sampling rate conversion
circuitry. PR2 powers down the mixer circuits (MIX1, MIX2,
National 3D Sound, Mono Out, Line Out). PR3 powers down
V
REF in addition to all the same mixer circuits as PR2. PR4
powers down the AC Link digital interface – see Figure 8 for
signal powerdown timing. PR5 disables internal clocks. PR6
and PR7 are not used.
BIT#
BIT
Function: Status
0
ADC
1 = ADC section ready to
transmit data
1
DAC
1 = DAC section ready to
accept data
2
ANL
1 = Analog mixers ready
3
REF
1 = V
REF is up to nominal level
BIT#
BIT
Function: Powerdown
8
PR0
1 = Powerdown ADCs and
Record Select Mux
9
PR1
1 = Powerdown DACs
10
PR2
1 = Powerdown Analog Mixer
(V
REF still on)
11
PR3
1 = Powerdown Analog Mixer
(V
REF off)
12
PR4
1 = Powerdown AC Link digital
interface (BIT_CLK off)
13
PR5
1 = Disable Internal Clock
14
PR6
Not Used
15
PR7
Not Used
Default: 000Xh
EXTENDED AUDIO ID REGISTER (28h)
This read-only register identifies which AC ’97 Extended
Audio features are supported. The LM4548A features VRA
(Variable Rate Audio) and ID1, ID0 (Multiple Codec support).
VRA is indicated by a "1" in bit 0. The two MSBs, ID1 and
ID0, show the current Codec Identity as defined by the
LM4548A
www.national.com
23
相關(guān)PDF資料
PDF描述
LM4548VHX SPECIALTY CONSUMER CIRCUIT, PQFP48
LM4548VH/NOPB SPECIALTY CONSUMER CIRCUIT, PQFP48
LM4548VHX/NOPB SPECIALTY CONSUMER CIRCUIT, PQFP48
LM4549AVH/NOPB SPECIALTY CONSUMER CIRCUIT, PQFP48
LM4550VH/NOPB SPECIALTY CONSUMER CIRCUIT, PQFP48
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM4548AVHX 制造商:Rochester Electronics LLC 功能描述:- Bulk
LM4548VH 制造商:Texas Instruments 功能描述:
LM4549 制造商:NSC 制造商全稱:National Semiconductor 功能描述:AC ’97 Rev 2.1 Codec with Sample Rate Conversion and National 3D Sound
LM4549A 制造商:NSC 制造商全稱:National Semiconductor 功能描述:AC ’97 Rev 2.1 Codec with Sample Rate Conversion and National 3D Sound
LM4549AVH 制造商:Rochester Electronics LLC 功能描述:AC97 REV2.1 CODEC - Bulk 制造商:OC White Company 功能描述:Audio Codec 2ADC / 2DAC 18-Bit 48-Pin LQFP Tray
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*