|
|
Número de pieza | ADC3214 | |
Descripción | High Speed 14-Bit 1MHz Sampling A/D Converter | |
Fabricantes | Analogic Corporation | |
Logotipo | ||
Hay una vista previa y un enlace de descarga de ADC3214 (archivo pdf) en la parte inferior de esta página. Total 6 Páginas | ||
No Preview Available ! www.DataSheet4U.com
ADC3214
High Speed, 14-Bit, 1 MHz,
Sampling A/D Converter
With Built-in Sample-and-Hold Amplifier
Introduction
The ADC3214 is a 14-bit, 1 MHz A/D converter with a built-in sample-
and-hold amplifier. It was designed for use in applications requiring high
speed and high resolution front ends, such as ATE, medical imaging,
radar, communications, and analytical instrumentation. The ADC3214 is a
cost-effective solution for both time and frequency domain applications. It
is capable of digitizing a 500 kHz signal at a 1 MHz rate with a guarantee
of no missing codes. Signal-to-noise ratio is 76 dB at input frequencies
from DC to 100 kHz. With a 1 MHz sampling rate and a full-scale step re-
sponse to 14-bit accuracy of one conversion, this sampling A/D converter
is ideally suited for applications with multiplexed signal sources.
The ADC3214 utilizes the latest surface-mount technologies to produce a
cost-effective, high-performance part in a 2" x 3" fully shielded package.
It is designed around a two-pass, subranging architecture that integrates
a low distortion sample-and-hold amplifier, precision voltage reference,
all the necessary timing circuitry and tri-state CMOS/TTL-compatible out-
puts for ease of system integration.
Continued on page 3.
Signal In
Range 1
Range 2
S/H Out
A/D In
S/H
Amplifier
Scaling &
Offset
Circuit
P1
P2
8-Bit
ADC
Ext. Off
Adj.
Ext. Gain
Adj.
+Ref. Out
Ref. ∑
Ckt.
Ref.
Trigger
Enable
ADC Clk.
Ref.
4-Bit
Linear
DAC
Figure 1. ADC3214 Functional Block Diagram.
+15V
Ana. Rtn.
–15V
+5V
Dig. Rtn.
L
o
g B1-B14
i
c
O/U Flow
EOC
Features
u 14-Bit Resolution
u 1 MHz Throughput Rate
u Reduced Cost
u Reduced Size
u No Missing Codes:
0°C to +60°C
u Signal-to-Noise Ratio:
76 dB
u Peak Distortion:
–82 dB @ 100 kHz
u Total Harmonic Distortion:
–80 dB @ 100 kHz
u Ease of Use
u Built-In S/H Amplifier
u TTL Compatibility
u High Input Impedance
(100 MΩ)
Applications
u Radar
u Analytical Instrumentation
u Spectroscopy
u Digital Telecommunications
u Automatic Test Equipment
u High-Resolution Imaging
u Medical Data Acquisition
u Multiplexed Data Acquisition
1 page www.DataSheet4U.com
1st Pass
Analog
Input
S/H
Amplifier
Scaling &
Offset Circuit
x0.4
2V p-p
8-Bit
ADC
To Summing Amp
for 2nd Pass
To 14-Bit DAC
for 2nd Pass
From
S/H Out
8 MSBs
From 1st
Pass
Logic
14-Bit
Linear
DAC
2nd Pass
∑ X25.6
0.5V p-p
8-Bit
ADC
Overlap
Logic
Logic
B1-B14
O/U
Figure 7. Simplified Block Diagram.
In the second pass, the output of the D/A converter is
subtracted from the output of the S/H amplifier. The
nominal error voltage of ±0.5 LSB (at the 8-bit level it is
5V/256 or 19.5 mV) is amplified by 25.6 to achieve 1/4
full scale range of the flash ADC, thus allowing a 2-bit
overlap safety margin. The effective resolution there-
fore becomes the digital summation of two 8-bit results
with the 2 LSBs of Pass 1 overlapping the 2 MSBs of
Pass 2. At approximately 550 ns after trigger, the error
signal has settled to 14-bit accuracy and the ADC then
digitizes the second pass. The internal logic then
places the S/H back into the Sample mode to begin
acquiring the next sample. The second pass data is
latched into the output tri-state registers and the con-
version is now complete. This is marked by a high-to-
low transition of the EOC pulse with the data valid 20
ns prior to EOC.
The ADC3214 has a tri-state output structure. Users
can enable the fourteen data bits and the
Overflow/Underflow bit with the ENABLE pin. This fea-
ture makes it possible to transfer data from the
ADC3214 to a microprocessor bus. However, to pre-
vent the coupling of high frequency noise from the mi-
croprocessor bus into the A/D converter, the output
data must be buffered (see Figure 8).
The 1/4 full scale range, or 2-bit overlap in the second
pass, is a scheme used in the ADC3214 to provide an
output word that is accurate and linear to 14 bits. This
method corrects for gain and linearity errors in the am-
plifying circuitry, as well as the 8-bit flash A/D convert-
er. Without the use of this overlapping correction
scheme, it would be necessary that all the components
in the ADC3214 be accurate to the 14-bit level. While
such a design might be possible to realize on a labora-
tory benchtop, it clearly would be impractical to
achieve on a production basis. The key to the conver-
sion technique used in the ADC3214 is the 14-bit ac-
curate and 14-bit linear D/A converter, which serves as
the reference element for the conversion’s second
pass. The use of proprietary sub-ranging architecture
in the ADC3214 results in a sampling A/D converter
that offers unprecedented speed and transfer charac-
teristics at the 14-bit level.
5 Page |
Páginas | Total 6 Páginas | |
PDF Descargar | [ Datasheet ADC3214.PDF ] |
Número de pieza | Descripción | Fabricantes |
ADC321 | Single & Dual Output DC/DC Converters | MPS Industries |
ADC3214 | High Speed 14-Bit 1MHz Sampling A/D Converter | Analogic Corporation |
Número de pieza | Descripción | Fabricantes |
SLA6805M | High Voltage 3 phase Motor Driver IC. |
Sanken |
SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
Analog Devices |
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |