Analog Devices Inc. LTC2408CG#TRPBF

Overview

LTC2408CG#TRPBF from Analog Devices (formerly Linear Technology) is an 8-channel, 24-bit micropower delta-sigma ADC with no-latency digital filtering, 4 ppm INL, 0.3 ppm RMS noise, and integrated oscillator. It operates from 2.7V to 5.5V, accepts reference voltages from 0.1V to VCC, and delivers valid first-conversion results after channel change-enabling precise, low-power data acquisition in weight scales and industrial sensor interfaces.

For engineers reviewing the LTC2408CG#TRPBF datasheet, LTC2408CG#TRPBF pinout, LTC2408CG#TRPBF application, or LTC2408CG#TRPBF equivalent, key selection criteria include its 28-lead SSOP package, 50/60 Hz notch rejection ≥110 dB, single-cycle filter settling, extended input range (–12.5% to +112.5% VREF), and SPI/MICROWIRE-compatible 4-wire interface for multiplexed sensor systems.

Technical Context

The LTC2408CG#TRPBF uses a 24-bit delta-sigma modulator with decimating FIR filtering and auto-calibration per conversion cycle-ensuring stable offset and full-scale performance across temperature and supply voltage variations. Its internal oscillator eliminates external timing components and enables fixed 50 Hz or 60 Hz ±2% notch rejection when FO is tied to GND or VCC.

Channel selection is performed via 4-bit serial address on DIN synchronized to CLK while CSMUX is high; the selected channel appears at MUXOUT and is sampled by the ADC core. Data output is 32-bit MSB-first over SDO, with bit 31 indicating end-of-conversion (EOC), and no latency between channel change and valid result.

Key Specifications

Pinout & Package

Package: 28-lead plastic SSOP (G package), 5.6 mm × 10.2 mm body, 0.65 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 24-bit delta-sigma ADC applications.

Compared with ADS1248IPWR and MAX11206ETL+, the LTC2408CG#TRPBF uniquely combines 8-channel capability, integrated 110 dB notch filtering, and no-latency operation in a mature SSOP package-making it optimal for cost-sensitive, mains-noise-prone industrial DAQ where first-conversion validity is mandatory.

Availability

LTC2408CG#TRPBF is available at Aetrix Electronics and suitable for weight scales, direct temperature measurement, gas analyzers, strain gauge transducers, and industrial process control requiring stable component supply and long-term manufacturability.

Supply support for LTC2408CG#TRPBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2408CG#TRPBF belongs to ADI's legacy Linear Technology precision ADC product line, designed specifically for low-power, high-accuracy sensor interfacing in noise-sensitive environments-emphasizing ease of use, self-calibration, and robustness against EMI and supply variation.

FAQ

What is the maximum sample rate of the LTC2408CG#TRPBF?

The LTC2408CG#TRPBF achieves a maximum output rate of approximately 7.68 SPS when FO is grounded (50 Hz rejection mode) and 6.4 SPS when FO is tied to VCC (60 Hz rejection mode). With an external oscillator, the output rate is fEOSC/20480, enabling user-defined rates up to ~15 SPS (at 307.2 kHz). The LTC2408CG#TRPBF does not support oversampling to increase effective resolution beyond 24 bits.

Does the LTC2408CG#TRPBF require external calibration components?

No, the LTC2408CG#TRPBF performs automatic offset and full-scale calibration on every conversion cycle using on-chip circuitry-no external resistors, capacitors, or calibration routines are needed. This ensures long-term stability of INL (<4 ppm) and total unadjusted error (<10 ppm) across temperature and supply voltage changes without user intervention. The LTC2408CG#TRPBF maintains this behavior across its full 0°C to 70°C operating range.

Can the LTC2408CG#TRPBF operate with a 1.8V reference voltage?

Yes, the LTC2408CG#TRPBF supports reference voltages from 0.1 V to VCC (2.7–5.5 V), so a 1.8 V reference is fully compliant. At 1.8 V, the input range becomes –0.225 V to +2.025 V, and RMS noise remains ~1.5 µVRMS-preserving effective resolution. However, INL improves slightly (due to lower reference-related nonlinearity), while full-scale error stays within 4 ppm. The LTC2408CG#TRPBF maintains all specified timing and interface behavior at this reference level.

How does the LTC2408CG#TRPBF handle input signals outside its extended range?

When input voltage falls below –0.125 × VREF or exceeds +1.125 × VREF, the LTC2408CG#TRPBF clamps the output code to the corresponding boundary value-no saturation artifacts or undefined behavior occur. For example, with VREF = 2.5 V, inputs < –0.3125 V or > +2.8125 V produce minimum or maximum 24-bit codes. Absolute maximum ratings (–0.3 V to VCC + 0.3 V) still apply; exceeding those risks ESD diode conduction and increased leakage. The LTC2408CG#TRPBF tolerates such conditions without damage if current-limited.

Is the LTC2408CG#TRPBF pin-compatible with the LTC2404CG#TRPBF?

Yes, the LTC2408CG#TRPBF is pin-compatible with the LTC2404CG#TRPBF in the 28-lead SSOP package. Pins CH4–CH7 (13–14, 15, 17) are no-connect on the LTC2404CG#TRPBF but function as active analog inputs on the LTC2408CG#TRPBF; all other pins-including power, reference, interface, and control-share identical functions and electrical characteristics. This allows direct upgrade from 4- to 8-channel capability without PCB redesign.