LTC2401 Datasheet, PDF (1/12 Pages) Linear Technology – 1-/2-Channel 24-Bit uPower No Latency ADC in MSOP-10

Final Electrical Specifications
LTC2401/LTC2402
1-/2-Channel 24-Bit µPower
No Latency ∆Σ^TMADC in MSOP-10
FEATURES
DESCRIPTIO
January 2000
s _{24-Bit ADC in Tiny MSOP-10 Package}
s _{1- or 2-Channel Inputs}
s _{Automatic Channel Selection (Ping-Pong) (LTC2402)}
s _{Zero Scale and Full Scale Set for Reference}
and Ground Sensing
s _{4ppm INL, No Missing Codes}
s _{4ppm Full-Scale Error}
s _{0.5ppm Offset}
s _{0.6ppm Noise}
s _{Internal Oscillator—No External Components Required}
s _{110dB Min, 50Hz/60Hz Notch Filter}
s _{Single Conversion Settling Time for}
Multiplexed Applications
s _{Reference Input Voltage: 0.1V to VCC}
s _{Live Zero—Extended Input Range Accommodates}
12.5% Overrange and Underrange
s _{Single Supply 2.7V to 5.5V Operation}
s _{Low Supply Current (200µA) and Auto Shutdown}
U
APPLICATIO S
s _{Weight Scales}
s _{Direct Temperature Measurement}
s _{Gas Analyzers}
s _{Strain-Gage Transducers}
s _{Instrumentation}
s _{Data Acquisition}
s _{Industrial Process Control}
The LTC^®2401/LTC2402 are 1- and 2-channel 2.7V to
5.5V micropower 24-bit analog-to-digital converters with
an integrated oscillator, 4ppm INL and 0.6ppm RMS
noise. These ultrasmall devices use delta-sigma technol-
ogy and a new digital filter architecture that settles in a
single cycle. This eliminates the latency found in conven-
tional ∆Σ converters and simplifies multiplexed applica-
tions.
Through a single pin, the LTC2401/LTC2402 can be
configured for better than 110dB rejection at 50Hz or
60Hz ±2%, or can be driven by an external oscillator for
a user defined rejection frequency in the range 1Hz to
120Hz. The internal oscillator requires no external fre-
quency setting components.
These converters accept an external reference voltage
from 0.1V to V_CC. With an extended input conversion
range of –12.5% V_REF to 112.5% V_REF (V_REF = FS_SET –
ZS_SET), the LTC2401/LTC2402 smoothly resolve the off-
set and overrange problems of preceding sensors or
signal conditioning circuits.
The LTC2401/LTC2402 communicate through a 2- or
3-wire digital interface that 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
2.7V TO 5.5V
1µF
REFERENCE VOLTAGE
ZS_SET + 0.1V TO V_CC
ANALOG
INPUT RANGE
–0.12V_REF TO 1.12V_REF
(V_REF = FS_SET – ZS_SET)
0V TO FS_SET – 100mV
1
V_CC
10
F_O
LTC2402
2
FS_SET
9
SCK
3
CH1
SDO ⁸
4
CH0
7
CS
5
6
ZS_SET GND
V_CC
= INTERNAL OSC/50Hz REJECTION
= EXTERNAL CLOCK SOURCE
= INTERNAL OSC/60Hz REJECTION
3-WIRE
SPI INTERFACE
24012 TA01
Pseudo Differential Bridge Digitizer
1
V_CC
2 ^LTC2402
FS_{SET SCK} 9
4
CH0
8
SDO
3
CH1
CS ⁷
2.7V TO 5.5V
3-WIRE
SPI INTERFACE
5
ZS_SET
GND
6
10
F_O
INTERNAL OSCILLATOR
60Hz REJECTION
24012TA02
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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