LTC2436-1_15 Datasheet, PDF (1/28 Pages) Linear Technology – 2-Channel Differential Input 16-Bit No Latency ADC

LTC2436-1
2-Channel Differential Input
16-Bit No Latency ∆Σ ADC
FEATURES
s _{2-Channel Differential Input with Automatic}
Channel Selection (Ping-Pong)
s _{Low Supply Current: 200µA, 4µA in Autosleep}
s _{Differential Input and Differential Reference with}
GND to V_CC Common Mode Range
s _{0.12LSB INL, No Missing Codes}
s _{0.16LSB Full-Scale Error and 0.006LSB Offset}
s _{800nV RMS Noise, Independent of VREF}
s _{No Latency: Digital Filter Settles in a Single Cycle and}
Each Channel Conversion is Accurate
s _{Internal Oscillator—No External Components}
Required
s _{87dB Min, 50Hz and 60Hz Notch Filter}
s _{Narrow SSOP-16 Package}
s _{Single Supply 2.7V to 5.5V Operation}
s _{Pin Compatible with the 24-Bit LTC2412}
U
APPLICATIO S
s _{Direct Sensor Digitizer}
s _{Weight Scales}
s _{Direct Temperature Measurement}
s _{Gas Analyzers}
s _{Strain-Gage Transducers}
s _{Instrumentation}
s _{Data Acquisition}
s _{Industrial Process Control}
DESCRIPTIO
The LTC^®2436-1 is a 2-channel differential input mi-
cropower 16-bit No Latency ∆Σ^TM analog-to-digital con-
verter with an integrated oscillator. It provides 0.5LSB
INL and 800nV RMS noise independent of V_REF. The two
differential channels convert alternately with a channel
identification included in the conversion result. It uses
delta-sigma technology and provides single conversion
settling of the digital filter. Through a single pin, the
LTC2436-1 can be configured for better than 87dB input
differential mode rejection at 50Hz and 60Hz ±2%, or it
can be driven by an external oscillator for a user defined
rejection frequency. The internal oscillator requires no
external frequency setting components.
The converter accepts any external differential reference
voltage from 0.1V to V_CC for flexible ratiometric and
remote sensing measurement configurations. The full-
scale differential input range is from – 0.5 •␣ V_REF to 0.5 •
V_REF. The reference common mode voltage, V_REFCM, and
the input common mode voltage, V_INCM, may be indepen-
dently set anywhere between GND and V_CC. The DC
common mode input rejection is better than 140dB.
The LTC2436-1 communicates through a flexible 3-wire
digital interface which is compatible with SPI and
MICROWIRE^TM protocols.
, LTC and LT are registered trademarks of Linear Technology Corporation.
No Latency ∆Σ is a trademark of Linear Technology Corporation.
MICROWIRE is a trademark of National Semiconductor Corporation.
TYPICAL APPLICATIO
5V REF
4.9k
(100mV)
100Ω
THERMOCOUPLE
1µF
1
V_CC
2 _REF+
4 _CH0+
14
F_O
LTC2436-1
5 _CH0–
13
SCK
3 _REF–
12
SDO
6 _CH1+
7 _CH1–
8, 9, 10, 15, 16
GND
11
CS
24361 TA01
= EXTERNAL CLOCK SOURCE
= INTERNAL OSC/SIMULTANEOUS
50Hz/60Hz REJECTION
3-WIRE
SPI INTERFACE
Effective Resolution vs V_REF
90
80
70
60
50
40
30
20
10
0
0
1
2
3
4
5
V_REF (V)
24361 TA02
*COMBINES EFFECTS OF PEAK-TO-PEAK NOISE
AND 16-BIT STEP SIZE (V_REF/2¹⁶)
24361f
1