- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄367829 > PCM78P 16-Bit Audio ANALOG-TO-DIGITAL CONVERTER PDF資料下載
參數(shù)資料
| 型號： | PCM78P |
| 英文描述： | 16-Bit Audio ANALOG-TO-DIGITAL CONVERTER |
| 中文描述： | 16位音頻模擬數(shù)字轉(zhuǎn)換器 |
| 文件頁數(shù)： | 9/16頁 |
| 文件大?。?/td> | 241K |
| 代理商： | PCM78P |
PCM78
9
FIGURE 2. Block Diagram of Distortion Test Circuit.
DISCUSSION OF
SPECIFICATIONS
TOTAL HARMONIC DISTORTION
Evaluating distortion specifications can be a difficult task,
as distortion is often specified in different ways. Total
Harmonic Distortion (THD) is defined as the ratio of the
square root sum of the squares of the value of rms harmonics
to the value of the rms fundamental and is expressed in
percent or dB. Note that this measurement only includes
energy present in those frequencies which would contain
harmonics, and therefore is less than Total Harmonic
Distortion plus Noise.
The Total Harmonic Distortion plus Noise (THD+N) is
defined as the ratio of the square root of the sum of the
squares of the value of the rms harmonics and rms noise to
the value of the rms fundamental and is expressed in percent
or dB. This is the most meaningful measurement of a
dynamic converter’s performance because it includes all
energy present in the signal that is not fundamental. A block
diagram of the test circuit used to measure the THD and
THD+N of the PCM78 is shown in Figure 2. This digital
system is capable of differentiating harmonic energy and
noise; conventional distortion analyzers which operate on a
tracking notch filter principle cannot distinguish this energy,
and therefore only measure THD+N. Unfortunately, in the
past, these systems were used for measuring distortion
performance of converters, and the distortion was often
simply specified as “THD”, when in fact it was really
THD+N. For this reason, it is often confusing to compare
specifications of converters unless one knows exactly what
was being measured.
If we assume that the error due to the test circuit of Figure
2 is negligible, then the rms value of the PCM78 error
referred to the input can be shown to be
where N is the number of samples, E
L
(i) is the linearity
error at each sample, E
Q
(i) is the quantization error at each
FIGURE 3. Block Diagram of Histogram Test.
Sync
Timing
B&K
Digital
Oscillator
Convert Command
SHC702
PCM78
Serial-To-Parallel
IEEE-488
Communication
HP-330
Scientific
Computer
Digital Distortion
Analyzer Software
DataPhysics Corp
0
–20
–40
–60
–80
–100
–120
25
S
Frequency (kHz)
50
75
0.0
100
Sync
Timing
B&K
Digital
Oscillator
Convert Command
SHC702
PCM78
Serial-To-Parallel
64k
Memory
IEEE-488
HP-330
Scientific
Computer
2
1
0
–1
–2
E
Codes
2048
4095
0
1024
3072
THD
+
N
=
1
N
E
L
(i)
+
E
Q
(i)
+
E
N
(i)
[
]
2
i
=
1
N
∑
E
rms
X 100%
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| PCM78 | 16-Bit Audio ANALOG-TO-DIGITAL CONVERTER |
| PCM95G | GEHAEUSE WASSERD DECKEL GRAU 230X140X95 |
| BMP | MOTAGEPLATTE FUER 223256 268 311 323 |
| PCM95T | GEHAEUSE WASSERD DECK TRANSP 230X140X95 |
| PCNET | PCnet - PCnet Family Network Driver Installation Guide. Part 2 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| PCM-79 | 功能描述:電線鑒定 Pre-Printed WM Card, Vinyl Cloth, .22" W RoHS:否 制造商:TE Connectivity / Q-Cees 產(chǎn)品:Labels and Signs 類型: 材料:Vinyl 顏色:Blue 寬度:0.625 in 長度:1 in |
| PCM-7T1 | 制造商:Panduit Corp 功能描述: |
| PCM-7T2 | 制造商:Panduit Corp 功能描述:Call vendor for pricing |
| PCM-8 | 功能描述:電線鑒定 1.5" VINYL CLOTH #8 RoHS:否 制造商:TE Connectivity / Q-Cees 產(chǎn)品:Labels and Signs 類型: 材料:Vinyl 顏色:Blue 寬度:0.625 in 長度:1 in |
| PCM-80 | 功能描述:電線鑒定 Pre-Printed WM Card, Vinyl Cloth, .22" W RoHS:否 制造商:TE Connectivity / Q-Cees 產(chǎn)品:Labels and Signs 類型: 材料:Vinyl 顏色:Blue 寬度:0.625 in 長度:1 in |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。