LTC2496_15 Datasheet, PDF (1/32 Pages) Linear Technology – 16-Bit 8-/16-Channel ADC with Easy Drive Input Current Cancellation

LTC2496
16-Bit 8-/16-Channel
ΔΣ ADC with Easy Drive
Input Current Cancellation
Features
n _{Up to 8 Differential or 16 Single-Ended Inputs}
n _{Easy Drive Technology Enables Rail-to-Rail Inputs}
with Zero Differential Input Current
n _{Directly Digitizes High Impedance Sensors with}
Full Accuracy
n _{600nV RMS Noise (0.02 LSB Transition Noise)}
n _{GND to VCC Input/Reference Common Mode Range}
n _{Simultaneous 50Hz/60Hz Rejection}
n _{2ppm INL, No Missing Codes}
n _{1ppm Offset and 15ppm Full-Scale Error}
n _{No Latency: Digital Filter Settles in a Single Cycle,}
Even After a New Channel is Selected
n _{Single Supply 2.7V to 5.5V Operation (0.8mW)}
n _{Internal Oscillator}
n _{QFN 5mm × 7mm Package}
Applications
n _{Direct Sensor Digitizer}
n _{Direct Temperature Measurement}
n _{Instrumentation}
n _{Industrial Process Control}
Description
The LTC^®2496 is a 16-channel (8-differential) 16-bit No
Latency ΔΣ™ ADC with Easy Drive™ technology. The pat-
ented sampling scheme eliminates dynamic input current
errors and the shortcomings of on-chip buffering through
automatic cancellation of differential input current. This
allows large external source impedances, and rail-to-rail
input signals to be directly digitized while maintaining
exceptional DC accuracy.
The LTC2496 includes an integrated oscillator. This device
can be configured to measure an external signal (from
combinations of 16 analog input channels operating in
single ended or differential modes). It automatically rejects
line frequencies of 50Hz and 60Hz, simultaneously.
The LTC2496 allows a wide common mode input range
(0V to V_CC), independent of the reference voltage. Any
combination of single-ended or differential inputs can be
selected and the first conversion after a new channel is
selected is valid. Access to the multiplexer output enables
optional external amplifiers to be shared between all analog
inputs and auto calibration continuously removes their
associated offset and drift.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Typical Application
Data Acquisition System
2.7V TO 5.5V
CH0
CH1
•
••
CH7
CH8
•
••
CH15
16-CHANNEL
MUX
COM
MUXOUT/
V_CC
ADCIN
REF⁺
IN⁺
SDI
16-BIT ∆∑ ADC ^SCK
WITH EASY-DRIVE SDO
IN^–
CS
REF^–
MUXOUT/
ADCIN
f₀
OSC
2496 TA01a
0.1µF
10µF
4-WIRE
SPI INTERFACE
+FS Error vs R_SOURCE
80 _{VCC = 5V}
60
40
VVV^{RIINNE+–F}
=
=
=
5V
3.75V
1.25V
f_O = GND
20 ^{TA = 25°C}
C_IN = 1µF
0
–20
–40
–60
–80
1
10
100
1k
10k 100k
R_SOURCE (Ω)
2498 TA01b
For more information www.linear.com/LTC2496
2496fc
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