LTC2440 - 24-Bit High Speed Differential Delta Sigma ADC with Selectable Speed/Resolution

The LTC2440 is a high speed 24-bit No Latency Delta Sigma ADC with 5ppm INL and 5µV offset. It uses proprietary Delta Sigma architecture enabling variable speed and resolution with no latency. Ten speed/resolution combinations (6.9Hz/ 200nVRMS to 3.5kHz/25µVRMS) are programmed through a simple serial interface. Alternatively, by tying a single pin HIGH or LOW, a fast (880Hz/2µVRMS) or ultralow noise (6.9Hz, 200nVRMS, 50/60Hz rejection) speed/resolution combination can be easily selected. The accuracy (offset, full-scale, linearity, drift) and power dissipation are independent of the speed selected. Since there is no latency, a speed/resolution change may be made between conversions with no degradation in performance.

Following each conversion cycle, the LTC2440 automatically enters a low power sleep state. Power dissipation may be reduced by increasing the duration of this sleep state. For example, running at the 3.5kHz conversion speed but reading data at a 100Hz rate draws 240µA average current (1.1mW) while reading data at a 7Hz output rate draws only 25µA (125µW).The LTC2440 communicates through a flexible 3-wire or 4-wire digital interface that is compatible with the LTC2410 and is available in a narrow 16-lead SSOP package.

  • Up to 3.5kHz Output Rate
  • Selectable Speed/Resolution
  • 2µVRMS Noise at 880Hz Output Rate
  • 200nVRMS Noise at 6.9Hz Output Rate with Simultaneous 50/60Hz Rejection
  • 0.0005% INL, No Missing Codes
  • Autosleep Enables 20µA Operation at 6.9Hz
  • < 5µV Offset (4.5V < VCC < 5.5V, –40°C to 85°C)
  • Differential Input and Differential Reference with GND to VCC Common Mode Range
  • No Latency, Each Conversion is Accurate Even After an Input Step
  • Internal Oscillator—No External Components
  • Pin Compatible with the LTC2410
  • 24-Bit ADC in Narrow 16-Lead SSOP Package
Typical Application

  • High Speed Multiplexing
  • Weight Scales
  • Auto Ranging 6-Digit DVMs
  • Direct Temperature Measurement
  • High Speed Data Acquisition
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
Demo Boards
Part NumberDescriptionPrice
DC570ALTC2440CGN Demo Board | High Speed Delta Sigma ADC, (req DC2026)$50.00
Companion Boards
Part NumberDescriptionPrice
DC2026CLinduino One Isolated USB Demo Board: An Arduino- and QuikEval-Compatible Code Development Platform$75.00
Application Note
Reliability Data
Product Selector Card
LT Journal
Solutions Brochure
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LTC2440 Footprints and Symbols
LTC2440 - DC570A Linduino.INO File
LTC2440 - Linduino Header File
LTC2440 - Linduino.CPP File
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LTC24XX – Linduino.CPP File