Datasheet LTC2421, LTC2422 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 1-/2-Channel 20-Bit µPower No Latency ∆ΣTM ADCs in MSOP-10 |
| Pages / Page | 32 / 1 — FEATURES. DESCRIPTIO. 20-Bit ADCs in Tiny MSOP-10 Packages. 1- or … |
| File Format / Size | PDF / 381 Kb |
| Document Language | English |
FEATURES. DESCRIPTIO. 20-Bit ADCs in Tiny MSOP-10 Packages. 1- or 2-Channel Inputs. Single Supply 2.7V to 5.5V Operation
Model Line for this Datasheet
Text Version of Document
LTC2421/LTC2422 1-/2-Channel 20-Bit µPower No Latency ∆ΣTMADCs in MSOP-10
U FEATURES DESCRIPTIO
■
20-Bit ADCs in Tiny MSOP-10 Packages
The LTC®2421/LTC2422 are 1- and 2-channel 2.7V to 5.5V ■
1- or 2-Channel Inputs
micropower 20-bit analog-to-digital converters with an ■
Single Supply 2.7V to 5.5V Operation
integrated oscillator, 8ppm INL and 1.2ppm RMS noise. ■
Low Supply Current (200
µ
A) and Auto Shutdown
These ultrasmall devices use delta-sigma technology and ■
Automatic Channel Selection (Ping-Pong) (LTC2422)
a new digital filter architecture that settles in a single cycle. ■
No Latency: Digital Filter Settles in a
This eliminates the latency found in conventional ∆Σ
Single Conversion Cycle
converters and simplifies multiplexed applications. ■ 8ppm INL, No Missing Codes Through a single pin, the LTC2421/LTC2422 can be ■ 4ppm Full-Scale Error configured for better than 110dB rejection at 50Hz or ■ 0.5ppm Offset 60Hz ±2%, or can be driven by an external oscillator for ■ 1.2ppm Noise a user defined rejection frequency in the range 1Hz to ■ Zero Scale and Full Scale Set for Reference 120Hz. The internal oscillator requires no external fre- and Ground Sensing quency setting components. ■ Internal Oscillator—No External Components Required ■ 110dB Min, 50Hz/60Hz Notch Filter These converters accept an external reference voltage ■ Reference Input Voltage: 0.1V to V from 0.1V to VCC. With an extended input conversion CC ■ Live Zero—Extended Input Range Accommodates range of –12.5% VREF to 112.5% VREF (VREF = FSSET – 12.5% Overrange and Underrange ZSSET), the LTC2421/LTC2422 smoothly resolve the off- ■ Pin Compatible with LTC2401/LTC2402 set and overrange problems of preceding sensors or signal conditioning circuits.
U APPLICATIO S
The LTC2421/LTC2422 communicate through a 2- or ■ Weight Scales 3-wire digital interface that is compatible with SPI and ■ Direct Temperature Measurement MICROWIRETM protocols. ■ Gas Analyzers , LTC and LT are registered trademarks of Linear Technology Corporation. No Latency ∆Σ is a trademark of Linear Technology Corporation. ■ Strain Gauge Transducers MICROWIRE is a trademark of National Semiconductor Corporation. ■ Instrumentation ■ Data Acquisition ■ Industrial Process Control
U Pseudo Differential Bridge Digitizer TYPICAL APPLICATIO
2.7V TO 5.5V 2.7V TO 5.5V 1 1µF VCC= INTERNAL OSC/50Hz REJECTION VCC 1 10 V = EXTERNAL CLOCK SOURCE LTC2422 CC FO 2 = INTERNAL OSC/60Hz REJECTION FS 9 LTC2422 SET SCK REFERENCE VOLTAGE 2 9 FS 4 SET SCK ZS 8 3-WIRE SET + 0.1V TO VCC CH0 SDO SPI INTERFACE ANALOG INPUT RANGE 3 8 3-WIRE CH1 SDO 3 7 ZS SPI INTERFACE SET – 0.12VREF TO CH1 CS FSSET + 0.12VREF 4 7 (V CH0 CS 5 10 REF = FSSET – ZSSET) ZSSET FO INTERNAL OSCILLATOR 5 6 0V TO FS GND 60Hz REJECTION SET – 100mV ZSSET GND 6 24212 TA01 24012TA02 24212f 1
U FEATURES DESCRIPTIO
■
20-Bit ADCs in Tiny MSOP-10 Packages
The LTC®2421/LTC2422 are 1- and 2-channel 2.7V to 5.5V ■
1- or 2-Channel Inputs
micropower 20-bit analog-to-digital converters with an ■
Single Supply 2.7V to 5.5V Operation
integrated oscillator, 8ppm INL and 1.2ppm RMS noise. ■
Low Supply Current (200
µ
A) and Auto Shutdown
These ultrasmall devices use delta-sigma technology and ■
Automatic Channel Selection (Ping-Pong) (LTC2422)
a new digital filter architecture that settles in a single cycle. ■
No Latency: Digital Filter Settles in a
This eliminates the latency found in conventional ∆Σ
Single Conversion Cycle
converters and simplifies multiplexed applications. ■ 8ppm INL, No Missing Codes Through a single pin, the LTC2421/LTC2422 can be ■ 4ppm Full-Scale Error configured for better than 110dB rejection at 50Hz or ■ 0.5ppm Offset 60Hz ±2%, or can be driven by an external oscillator for ■ 1.2ppm Noise a user defined rejection frequency in the range 1Hz to ■ Zero Scale and Full Scale Set for Reference 120Hz. The internal oscillator requires no external fre- and Ground Sensing quency setting components. ■ Internal Oscillator—No External Components Required ■ 110dB Min, 50Hz/60Hz Notch Filter These converters accept an external reference voltage ■ Reference Input Voltage: 0.1V to V from 0.1V to VCC. With an extended input conversion CC ■ Live Zero—Extended Input Range Accommodates range of –12.5% VREF to 112.5% VREF (VREF = FSSET – 12.5% Overrange and Underrange ZSSET), the LTC2421/LTC2422 smoothly resolve the off- ■ Pin Compatible with LTC2401/LTC2402 set and overrange problems of preceding sensors or signal conditioning circuits.
U APPLICATIO S
The LTC2421/LTC2422 communicate through a 2- or ■ Weight Scales 3-wire digital interface that is compatible with SPI and ■ Direct Temperature Measurement MICROWIRETM protocols. ■ Gas Analyzers , LTC and LT are registered trademarks of Linear Technology Corporation. No Latency ∆Σ is a trademark of Linear Technology Corporation. ■ Strain Gauge Transducers MICROWIRE is a trademark of National Semiconductor Corporation. ■ Instrumentation ■ Data Acquisition ■ Industrial Process Control
U Pseudo Differential Bridge Digitizer TYPICAL APPLICATIO
2.7V TO 5.5V 2.7V TO 5.5V 1 1µF VCC= INTERNAL OSC/50Hz REJECTION VCC 1 10 V = EXTERNAL CLOCK SOURCE LTC2422 CC FO 2 = INTERNAL OSC/60Hz REJECTION FS 9 LTC2422 SET SCK REFERENCE VOLTAGE 2 9 FS 4 SET SCK ZS 8 3-WIRE SET + 0.1V TO VCC CH0 SDO SPI INTERFACE ANALOG INPUT RANGE 3 8 3-WIRE CH1 SDO 3 7 ZS SPI INTERFACE SET – 0.12VREF TO CH1 CS FSSET + 0.12VREF 4 7 (V CH0 CS 5 10 REF = FSSET – ZSSET) ZSSET FO INTERNAL OSCILLATOR 5 6 0V TO FS GND 60Hz REJECTION SET – 100mV ZSSET GND 6 24212 TA01 24012TA02 24212f 1
