Electronic Components Datasheet Search
  English  ▼

Delete All


Preview PDF Download HTML

LTC2439-1 Datasheet(PDF) 26 Page - Linear Technology

Part No. LTC2439-1
Description  8-/16-Channel 16-Bit No Latency Delta-Sigma ADC
Download  28 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  LINER [Linear Technology]
Direct Link  http://www.linear.com
Logo LINER - Linear Technology

LTC2439-1 Datasheet(HTML) 26 Page - Linear Technology

Back Button LTC2439-1 Datasheet HTML 20Page - Linear Technology LTC2439-1 Datasheet HTML 21Page - Linear Technology LTC2439-1 Datasheet HTML 22Page - Linear Technology LTC2439-1 Datasheet HTML 23Page - Linear Technology LTC2439-1 Datasheet HTML 24Page - Linear Technology LTC2439-1 Datasheet HTML 25Page - Linear Technology LTC2439-1 Datasheet HTML 26Page - Linear Technology LTC2439-1 Datasheet HTML 27Page - Linear Technology LTC2439-1 Datasheet HTML 28Page - Linear Technology  
Zoom Inzoom in Zoom Outzoom out
 26 / 28 page
background image
First, a change in fEOSC will result in a proportional change
in the internal notch position and in a reduction of the
converter differential mode rejection at the power line
frequency. In many applications, the subsequent perfor-
mance degradation can be substantially reduced by rely-
ing upon the LTC2439-1’s exceptional common mode
rejection and by carefully eliminating common mode to
differential mode conversion sources in the input circuit.
The user should avoid single-ended input filters and
should maintain a very high degree of matching and
symmetry in the circuits driving the IN+ and INpins.
Second, the increase in clock frequency will increase
proportionally the amount of sampling charge transferred
through the input and the reference pins. If large external
input and/or reference capacitors (CIN, CREF) are used, the
previous section provides formulae for evaluating the
effect of the source resistance upon the converter perfor-
mance for any value of fEOSC. If small external input and/
or reference capacitors (CIN, CREF) are used, the effect of
the external source resistance upon the LTC2439-1 typical
performance can be inferred from Figures 14, 15, 19 and
20 in which the horizontal axis is scaled by 139,800/fEOSC.
Third, an increase in the frequency of the external oscilla-
tor above 460800Hz (a more than 3
× increaseintheoutput
data rate) will start to decrease the effectiveness of the
internal autocalibration circuits. This will result in a pro-
gressive degradation in the converter accuracy and linear-
ity. Typical measured performance curves for output data
rates up to 100 readings per second are shown in Fig-
ures 24, 25, 26, 27, 28 and 29. In order to obtain the
highest possible level of accuracy from this converter at
output data rates above 20 readings per second, the user
is advised to maximize the power supply voltage used and
to limit the maximum ambient operating temperature. In
certain circumstances, a reduction of the differential refer-
ence voltage may be beneficial.
Increasing Input Resolution by Reducing Reference
The resolution of the LTC2439-1 can be increased by
reducing the reference voltage. It is often necessary to
amplify low level signals to increase the voltage resolution
of ADCs that cannot operate with a low reference voltage.
The LTC2439-1 can be used with reference voltages as low
as 100mV, corresponding to a
16-bit resolution. Reducing the reference voltage is func-
tionally equivalent to amplifying the input signal, however
no amplifier is required.
The LTC2439-1 has a 76
µV LSB when used with a 5V
reference, however the thermal noise of the inputs is
µVRMS and is independent of reference voltage. Thus
reducing the reference voltage will increase the resolution
at the inputs as long as the LSB voltage is significantly
larger than 1
µVRMS. A 325mV reference corresponds to a
µV LSB, which is approximately the peak-to-peak value
of the 1
code will be stable to
±1LSB for a fixed input. As the
reference is decreased further, the measured noise will
approach 1
Figure 30 shows two methods of dividing down the
reference voltage to the LTC2439-1. Where absolute accu-
racy is required, a precision divider such as the Vishay
MPM series dividers in a SOT-23 package may be used. A
51:1 divider provides a 98mV reference to the LTC2439-1
from a 5V source. The resulting
±49mV input range and
µV LSB is suitable for thermocouple and 10mV full-
scale strain gauge measurements.
If high initial accuracy is not critical, a standard 2%
resistor array such as the Panasonic EXB series may be
used. Single package resistor arrays provide better tem-
perature stability than discrete resistors. An array of eight
resistors can be configured as shown to provide a 294mV
reference to the LTC2439-1 from a 5V source. The fully
differential property of the LTC2439-1 reference terminals
allow the reference voltage to be taken from four central
resistors in the network connected in parallel, minimizing
drift in the presence of thermal gradients. This is an ideal
reference for medium accuracy sensors such as silicon
micromachined pressure and force sensors. These de-
vices typically have accuracies on the order of 2% and full-
scale outputs of 50mV to 200mV.

Similar Part No. - LTC2439-1

ManufacturerPart No.DatasheetDescription
Linear Technology
Linear Technology
LTC2439-1 LINER-LTC2439-1_15 Datasheet
325Kb / 28P
   8-/16-Channel 16-Bit No Latency ADC
More results

Similar Description - LTC2439-1

ManufacturerPart No.DatasheetDescription
Linear Technology
Linear Technology
LTC2439-1 LINER-LTC2439-1_15 Datasheet
325Kb / 28P
   8-/16-Channel 16-Bit No Latency ADC
Analog Devices
Analog Devices
AD7715 AD-AD7715_15 Datasheet
495Kb / 40P
   16-Bit, Sigma-Delta ADC
AD7715 AD-AD7715_17 Datasheet
897Kb / 41P
   16-Bit, Sigma-Delta ADC
AD7707 AD-AD7707_15 Datasheet
693Kb / 52P
   3-Channel 16-Bit, Sigma-Delta ADC
AD7707 AD-AD7707_17 Datasheet
775Kb / 53P
   3-Channel 16-Bit, Sigma-Delta ADC
ADUM7703 AD-ADUM7703 Datasheet
351Kb / 22P
   16-Bit, Isolated, Sigma-Delta ADC
AD7171 AD-AD7171 Datasheet
284Kb / 16P
   16-Bit Low Power Sigma-Delta ADC
REV. 0
AD7171 AD-AD7171_17 Datasheet
313Kb / 17P
   16-Bit, Low Power, Sigma-Delta ADC
Cirrus Logic
Cirrus Logic
CS5510 CIRRUS-CS5510 Datasheet
406Kb / 24P
   16-bit and 20-bit, 8-pin Sigma-Delta ADC
Maxim Integrated Products
Maxim Integrated Produc...
MX7705 MAXIM-MX7705 Datasheet
664Kb / 34P
   16-Bit, Low-Power, 2-Channel, Sigma-Delta ADC
Rev 0; 10/03
More results

Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28 

Datasheet Download

Go To PDF Page

Link URL

Privacy Policy
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com

Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz