Analog Devices Inc. LTC1409CSW#TRPBF

Overview

LTC1409CSW#TRPBF from Analog Devices (formerly Linear Technology) is a 12-bit, 800ksps successive-approximation ADC with true differential inputs, ±2.5V bipolar input range, 72.5dB S/(N+D) at 400kHz, and dual shutdown modes (4mW Nap, 10µW Sleep). It integrates a precision 2.5V reference, 20MHz full-power bandwidth sample-and-hold, and µP-compatible 12-bit parallel output - used in high-speed data acquisition and spectrum analysis systems.

For engineers reviewing the LTC1409CSW#TRPBF datasheet, LTC1409CSW#TRPBF pinout, LTC1409CSW#TRPBF application, or LTC1409CSW#TRPBF equivalent, key selection criteria include its no-pipeline-delay architecture, ±1LSB INL/DNL over temperature, differential common-mode rejection up to 60dB, and direct 3V logic interfacing via OVDD.

Technical Context

The LTC1409CSW#TRPBF employs a capacitive DAC-based successive approximation register (SAR) with internal zeroing switches and differential sample-and-hold circuitry. Its analog front-end supports simultaneous sampling of +AIN and –AIN with 150ns acquisition time and 5psRMS aperture jitter, enabling accurate undersampling of signals beyond Nyquist.

Digital interface uses asynchronous control with active-low CONVST start trigger, BUSY status flag, CS-selectable operation, and three-state parallel outputs (D11–D0) driven by separate OVDD supply. Power management includes NAP/SLP-configurable shutdown with 200ns wake-up latency from Sleep mode.

Key Specifications

Pinout & Package

Package: 28-lead plastic SO Wide (SW), RoHS-compliant, 11.27mm × 7.62mm body, 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit, high-speed SAR ADC applications.

Compared with ADS8325IPW and AD7865BSZ-1, the LTC1409CSW#TRPBF uniquely combines 800ksps speed, true differential input, integrated 2.5V reference, and no-pipeline-delay operation - making it optimal for high-fidelity, single-channel, wideband acquisition where timing determinism and noise immunity are critical.

Availability

LTC1409CSW#TRPBF is available at Aetrix Electronics and suitable for telecommunications baseband processing, digital signal processing front-ends, and multiplexed data acquisition systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LTC1409CSW#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 LTC1409CSW#TRPBF belongs to ADI's legacy Linear Technology precision data converter product line, designed specifically for high-speed, low-distortion, single-chip data acquisition in demanding instrumentation and communications applications.

FAQ

What is the maximum sampling rate supported by the LTC1409CSW#TRPBF?

The LTC1409CSW#TRPBF supports a maximum sampling rate of 800ksps, verified across the full operating temperature range (0°C to 70°C for C-grade). This rate is sustained with guaranteed AC performance including 72.5dB S/(N+D) at 400kHz input frequency and no pipeline delay - enabling real-time capture of signals up to the Nyquist limit without interpolation or buffering overhead. The LTC1409CSW#TRPBF achieves this using an internal clock and optimized SAR architecture.

Does the LTC1409CSW#TRPBF require an external reference voltage?

No, the LTC1409CSW#TRPBF operates with an internal 2.500V ±15ppm/°C temperature-compensated reference available at the VREF pin. This eliminates the need for external reference ICs in most applications. However, the VREF pin can be overdriven with an external reference (e.g., LT1019A-2.5) for improved accuracy or adjustable span - the internal reference amplifier provides 1.625× gain and REFCOMP requires ≥1µF bypass to AGND. The LTC1409CSW#TRPBF maintains full specification compliance with either source.

How does the differential input architecture of the LTC1409CSW#TRPBF improve noise immunity?

The LTC1409CSW#TRPBF features a unique differential sample-and-hold that acquires +AIN and –AIN simultaneously with 60dB common-mode rejection up to 100kHz and maintains >40dB rejection at 1MHz. This allows users to eliminate ground loops and reject coupled noise by measuring signals differentially at the source - for example, rejecting 50/60Hz mains interference in sensor bridges or motor current shunts. The LTC1409CSW#TRPBF's differential architecture also ensures INL/DNL remain independent of common-mode voltage, preserving linearity even with unbalanced drive conditions.

What are the power consumption characteristics of the LTC1409CSW#TRPBF in shutdown modes?

The LTC1409CSW#TRPBF offers two digitally selectable shutdown modes: Nap mode draws 4mW (1.2mA from ±5V supplies) with 200ns wake-up time, while Sleep mode consumes just 10µW (1µA total supply current) with slightly longer recovery. These modes are selected via the NAP/SLP pin and activated by pulling SHDN low. Both states retain register state and reference bias - allowing rapid resumption of full-speed operation without recalibration. The LTC1409CSW#TRPBF's low-power capability supports battery-operated test equipment and energy-conscious instrumentation.

Can the LTC1409CSW#TRPBF interface directly with 3V microcontrollers?

Yes, the LTC1409CSW#TRPBF supports direct 3V logic interfacing via its dedicated OVDD pin (Pin 27), which powers the D11–D0 output drivers independently of AVDD. When OVDD is connected to a 3V supply, the parallel outputs meet 3V logic thresholds (VOH ≥ 2.4V, VOL ≤ 0.4V) while maintaining full timing specifications. This eliminates level-shifting components and simplifies integration with ARM Cortex-M, PIC, or RISC-V microcontrollers. The LTC1409CSW#TRPBF retains all performance specs - including 800ksps throughput and 72.5dB S/(N+D) - under 3V output drive conditions.