LTC2428CG#PBF

Analog To Digital Converters (ADC) Overview

The LTC2428CG#PBF is an 8-channel, 20-bit micropower delta-sigma analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates on a single supply voltage ranging from 2.7V to 5.5V and features an integrated oscillator with no external frequency-setting components required. The device provides 8ppm integral nonlinearity (INL), 1.2ppm RMS noise, and a minimum of 110dB rejection at 50Hz or 60Hz. It utilizes a flexible 4-wire digital interface compatible with SPI and MICROWIRE protocols. Key specifications include a total unadjusted error of 8ppm, a full-scale error of 4ppm, and an offset error of 0.5ppm. The ADC supports live zero functionality with an extended input range of –12.5% to 112.5% of VREF.

Analog To Digital Converters (ADC) Feature Summary

• 8-Channel Multiplexer: Supports simultaneous connection of up to eight analog inputs (CH0–CH7) with break-before-make switching.
• No Latency Conversion: Digital filter settles in a single cycle; the first conversion after channel change is valid.
• Micropower Operation: Low supply current of 200µA in conversion mode and 20µA in auto shutdown/sleep mode.
• Integrated Oscillator: Internal clock eliminates need for external crystals, supporting 50Hz/60Hz notch filtering via FO pin configuration.

Analog To Digital Converters (ADC) Applications

• Weigh Scales
• Direct Temperature Measurement
• Gas Analyzers
• Strain-Gage Transducers
• Industrial Process Control

Analog To Digital Converters (ADC) Procurement Notes

Verify the package type is 28-lead plastic SSOP (G Package). Confirm the operating temperature range corresponds to the 'C' suffix (0°C to 70°C). Ensure the ordering suffix '#PBF' indicates lead-free RoHS compliance. Cross-reference the manufacturer part number LTC2428CG#PBF with official Analog Devices documentation to confirm availability and exact pinout compatibility.

Analog To Digital Converters (ADC) Selection Notes

Select the LTC2428 over the LTC2424 when eight multiplexed channels are required, as the LTC2424 only supports four. Choose the 'I' suffix variant if operation below 0°C down to –40°C is necessary. This component is suitable for applications requiring high precision without latency during channel switching. Verify that the reference voltage range (0.1V to VCC) aligns with system requirements for optimal noise performance.

Analog To Digital Converters (ADC) Part Context

The LTC2428 belongs to the LTC2424/LTC2428 family of 20-bit micropower ADCs. It is pin-compatible with the 24-bit LTC2404/LTC2408 series, allowing for design upgrades where the ZSSET pin is grounded. The device shares architectural similarities with other delta-sigma converters but distinguishes itself through its specific combination of 20-bit resolution, low power consumption, and integrated line-frequency rejection capabilities.

Analog To Digital Converters (ADC) Replacement Considerations

The LTC2424 is a direct functional substitute if only four channels are needed. The LTC2404/LTC2408 can serve as a replacement if the ZSSET pin is grounded, though output word length differs (24 bits vs 32 bits). No other cross-model substitutes are confirmed in the provided datasheet.