LTD2260中文资料模数转换器(ADC)数据手册Linearin规格书

描述 Description

The LTD226X family are high-precision, multi-channel, 40-kSPS, delta-sigma (Δ-Σ)analog-to-digital converters (ADCs). Features, for example, programmable gain amplifier(PGA), precise and low-drift voltage reference, monitors for fault detection, general purposeinput output options are included in this highly-integrated chip making it a single-chip solutionto deal with measurements tasks such as weigh scales, resistance temperature detectors(RTDs) and thermalcouple sensors. The main path of analog-to-digital conversion consists of an input multiplexer (5 channels forLTD2260 and 10 channels for LTD2261), a low-noise PGA, a 24-bit Δ-Σ modulator, a precise andlow-drift voltage reference, and a programmable digital filter. The 1 GΩ high input impedanceof the PGA minimizes the error induced by sensor loading. The device provide two individualcurrent source with programmable supplying current, that simplifies the circuit of RTDsmeasurements. The conversion is completed by a fourth-order Δ-Σ modulator combined with a flexible digitalfilter. The filter supports a simultaneous 50-Hz and 60-Hz rejection mode and single-cyclesettling mode. Associated with internal signal and reference monitors, a temperature sensorand CRC data verification, the output data is more reliable. The LTD226X family are available in 5 mm × 5 mm QFN packages and specified in temperaturerange from -40℃ to 125℃.

特性 Features

• High-precision, 24-bit delta-sigma ADC

• Low noise: 30 nVRMS (@20 SPS, gain=128)

• Linearity: 2 ppm

• 5 single-ended inputs or 3 differential inputs (LTD2260)

• 10 single-ended inputs or 5 differential inputs (LTD2261)\\

• PGA gain: 1 to 128

• Input voltage range: ±7 mV to ±5 V

• Data rate: 2.5 SPS to 40 kSPS

• Low drift 2.5 V reference: 2 ppm/℃

• Simultaneous 50-Hz and 60-Hz rejection mode

• Single-cycle settling mode

• PGA voltages and reference monitors

• 5 V or ±2.5 V supply

• Integrated temperature sensor

• Cyclic redundancy check

• Two individual current source

• Sensor burn-out detection

• 4 GPIOs available

• AC excitation for bridge sensors

• SPI compatible

应用 Application

• Temperature and pressure measurement

• Analog input modules in PLC and DCS

• Weigh scales and strain-gauge digitizers

• Scientific and lab instruments