參數(shù)資料
型號(hào): SP9841
英文描述: 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
中文描述: 8位八路,2象限乘法,BiCMOS工藝援
文件頁數(shù): 26/32頁
文件大?。?/td> 745K
代理商: SP9841
292
of generating a programmable pseudoground
voltage at the V
terminal. A pseudoground is
very useful if any channels are to be used in AC–
multiplying applications. In such applications,
the pseudoground will set the DC offset of the
output signal. The voltage output of this circuit
as the code is decreased is non–linear because
the DAC bootstraps the increased output volt-
age by a larger fraction at each code. It is really
meant to be programmed only over a range of
codes between 104 and perhaps 60. It does
exhibit a fairly well–defined output, even if
non–intentional codes are programmed. For
codes above 112, the output stage resembles a
50 Ohm resistor to ground, and the V
output
will be near 1.3V, depending upon the loading at
the other V
IN
(X) inputs. For codes below 60, the
output voltage will continue to rise until limited
by available current through R
. Note that
R
supplies the actual current into V
, and
must be chosen in order to supply enough cur-
rent for all channels, especially if any of the
other eight inputs are to be grounded. A plot of
V
versus code is shown with the
Figure
, for
all other inputs either grounded or tied to the
supply.
Figure 12
shows a programmable gain/attenua-
tor section using the programmable VREFL
drive. The VREFL of each DAC is actually
internally connected. When the optional 45
μ
F
noise reduction capacitor is included, this cir-
cuit is capable of 86dB of SNR and 74 to 84dB
of SINAD at 1kHz, depending on the pro-
Figure 12. AC–Coupled, Programmable Gain/Attenuator with Bootstrapped Programmable Output DC Offset (V
REFL
Drive).
+
V
OUT
A
1/8 of SP9841
3
ICL8069
+ –
R
ISRC
2kOhm
Load DACA with code 90; sets V
REFL
=1.7V.
Then, load DACB with desired gain:
code 255 = +6dB
code 128 = 0dB
code 64 = –6dB
code 1 = –42dB
code 0 = –70dB
45μF*
301
1.22V
V
REFL
V
IN
A
*(Optional Noise Reduction)
+5V
+
V
OUT
B
1/8 of SP9841
V
REFL
V
IN
B
2.2μF
±0.75V
相關(guān)PDF資料
PDF描述
SP9841BN 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841BS 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841KN 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841KS 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9842 8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
SP9841BN 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841BS 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841KN 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9841KS 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC
SP9842 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:8-Bit Octal, 2-Quadrant Multiplying, BiCMOS DAC