參數資料
型號: AD7859L*
廠商: Analog Devices, Inc.
英文描述: 5V Low Power RS232 Transceiver; Package: PDIP; No of Pins: 16; Temperature Range: 0°C to +70°C
中文描述: 3 V至5 V單電源。 200 kSPS的8通道。 12位采樣ADC
文件頁數: 6/28頁
文件大?。?/td> 535K
AD7859/AD7859L
REV. A
–6–
Total Harmonic Distortion
Total harmonic distortion (THD) is the ratio of the rms sum of
harmonics to the fundamental. For the AD7859/AD7859L, it is
defined as:
THD
(
dB
)
=
20log
(
V
2
2
+
V
3
2
+
V
4
2
+
V
5
2
+
V
6
2
)
V
1
where V
1
is the rms amplitude of the fundamental and V
2
, V
3
,
V
4
, V
5
and V
6
are the rms amplitudes of the second through the
sixth harmonics.
Peak Harmonic or Spurious Noise
Peak harmonic or spurious noise is defined as the ratio of the
rms value of the next largest component in the ADC output
spectrum (up to f
S
/2 and excluding dc) to the rms value of the
fundamental. Normally, the value of this specification is deter-
mined by the largest harmonic in the spectrum, but for parts
where the harmonics are buried in the noise floor, it will be a
noise peak.
Intermodulation Distortion
With inputs consisting of sine waves at two frequencies, fa and
fb, any active device with nonlinearities will create distortion
products at sum and difference frequencies of mfa
±
nfb where
m, n = 0, 1, 2, 3, etc. Intermodulation distortion terms are
those for which neither m nor n are equal to zero. For example,
the second order terms include (fa + fb) and (fa – fb), while the
third order terms include (2fa + fb), (2fa – fb), (fa + 2fb) and
(fa – 2fb).
Testing is performed using the CCIF standard where two input
frequencies near the top end of the input bandwidth are used. In
this case, the second order terms are usually distanced in fre-
quency from the original sine waves while the third order terms
are usually at a frequency close to the input frequencies. As a
result, the second and third order terms are specified separately.
The calculation of the intermodulation distortion is as per the
THD specification where it is the ratio of the rms sum of the
individual distortion products to the rms amplitude of the sum
of the fundamentals expressed in dBs.
TERMINOLOGY
Integral Nonlinearity
This is the maximum deviation from a straight line passing
through the endpoints of the ADC transfer function. The end-
points of the transfer function are zero scale, a point 1/2 LSB
below the first code transition, and full scale, a point 1/2 LSB
above the last code transition.
Differential Nonlinearity
This is the difference between the measured and the ideal 1 LSB
change between any two adjacent codes in the ADC.
Unipolar Offset Error
This is the deviation of the first code transition (00 . . . 000 to
00 . . . 001) from the ideal AIN(+) voltage (AIN(–) + 1/2 LSB)
when operating in the unipolar mode.
Positive Full-Scale Error
This applies to the unipolar and bipolar modes and is the devia-
tion of the last code transition from the ideal AIN(+) voltage
(AIN(–) + Full Scale – 1.5 LSB) after the offset error has been
adjusted out.
Negative Full-Scale Error
This applies to the bipolar mode only and is the deviation of the
first code transition (10 . . . 000 to 10 . . . 001) from the ideal
AIN(+) voltage (AIN(–) – V
REF
/2 + 0.5 LSB).
Bipolar Zero Error
This is the deviation of the midscale transition (all 0s to all 1s)
from the ideal AIN(+) voltage (AIN(–) – 1/2 LSB).
Track/Hold Acquisition Time
The track/hold amplifier returns into track mode and the end of
conversion. Track/Hold acquisition time is the time required for
the output of the track/hold amplifier to reach its final value,
within
±
1/2 LSB, after the end of conversion.
Signal to (Noise + Distortion) Ratio
This is the measured ratio of signal to (noise + distortion) at the
output of the A/D converter. The signal is the rms amplitude of
the fundamental. Noise is the sum of all nonfundamental sig-
nals up to half the sampling frequency (f
S
/2), excluding dc. The
ratio is dependent on the number of quantization levels in the
digitization process; the more levels, the smaller the quantiza-
tion noise. The theoretical signal to (noise + distortion) ratio for
an ideal N-bit converter with a sine wave input is given by:
Signal to (Noise + Distortion) = (
6.02
N +
1.76
) dB
Thus for a 12-bit converter, this is 74 dB.
相關PDF資料
PDF描述
AD7859LAS 3 V to 5 V Single Supply, 200 kSPS 8-Channel, 12-Bit Sampling ADCs
AD7859L 3 V to 5 V Single Supply, 200 kSPS 8-Channel, 12-Bit Sampling ADCs(單電源,200kSPS 8通道12位采樣A/D轉換器)
AD7859 3 V to 5 V Single Supply, 200 kSPS 8-Channel, 12-Bit Sampling ADCs(單電源,200kSPS 8通道12位采樣A/D轉換器)
AD7861AP 11-Bit Resolution Simultaneous Sampling A/D Converter
AD7861 11-Bit Resolution Simultaneous Sampling A/D Converter(同時采樣11位A/D轉換器)
相關代理商/技術參數
參數描述
AD7859LAS 制造商:Analog Devices 功能描述:ADC Single SAR 100ksps 12-bit Parallel 44-Pin MQFP 制造商:Rochester Electronics LLC 功能描述:12-BIT 8 CH.PARALLEL 100 KSPS I.C. - Bulk 制造商:Analog Devices 功能描述:IC 12-BIT ADC
AD7859LAS3 制造商:AD 制造商全稱:Analog Devices 功能描述:3 V to 5 V Single Supply, 200 kSPS8-Channel, 12-Bit Sampling ADCs
AD7859LAS-REEL 制造商:Analog Devices 功能描述:ADC Single SAR 100ksps 12-bit Parallel 44-Pin MQFP T/R
AD7859LASZ 功能描述:IC ADC 12BIT 8CH 200KSPS 44-MQFP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1 系列:microPOWER™ 位數:8 采樣率(每秒):1M 數據接口:串行,SPI? 轉換器數目:1 功率耗散(最大):- 電壓電源:模擬和數字 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:24-VFQFN 裸露焊盤 供應商設備封裝:24-VQFN 裸露焊盤(4x4) 包裝:Digi-Reel® 輸入數目和類型:8 個單端,單極 產品目錄頁面:892 (CN2011-ZH PDF) 其它名稱:296-25851-6