Analog Devices Inc. LTC2302CDD#TRPBF

Overview

LTC2302CDD#TRPBF from Analog Devices (formerly Linear Technology) is a 1-channel, 12-bit successive approximation register (SAR) ADC with differential analog inputs (IN+, IN–), SPI/MICROWIRE-compatible serial interface, and internal conversion clock. It delivers 500ksps sampling rate, 72.8dB SINAD at 1kHz, and operates from a single 5V supply drawing only 2.8mA - ideal for precision battery-powered data acquisition systems requiring low-noise, high-resolution analog sensing.

For engineers reviewing the LTC2302CDD#TRPBF datasheet, LTC2302CDD#TRPBF pinout, LTC2302CDD#TRPBF application, or LTC2302CDD#TRPBF equivalent, key selection criteria include its guaranteed no-missing-codes performance, software-selectable unipolar/bipolar input range (±2.048V or 0–4.096V), separate OVDD output driver supply (2.7–5.25V), auto-shutdown scaling (14µA at 1ksps), and 10-pin 3mm × 3mm DFN package with exposed pad ground.

Technical Context

The LTC2302CDD#TRPBF implements a fully differential sample-and-hold circuit to suppress common-mode noise, paired with a 12-bit capacitive charge-redistribution DAC and SAR logic that sequences from MSB to LSB. Its internal conversion clock decouples timing from the external SCK, enabling SCK frequencies up to 40MHz regardless of sampling rate.

It supports differential input acquisition only (IN+ vs IN–), with polarity selectable via O/S bit in the 6-bit DIN command. The analog input presents 55pF capacitance in sample mode and draws ≤±1µA leakage current, while digital I/Os are compatible with 2.7–5.25V OVDD and tolerate 4.75–5.25V VDD.

Key Specifications

Pinout & Package

Package: 10-lead (3mm × 3mm) plastic DFN with exposed pad (Pin 11), rated for 0°C to 70°C operating temperature. Exposed pad must be soldered to PCB ground plane for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11100ETE+, the LTC2302CDD#TRPBF uniquely combines 12-bit no-missing-codes performance, 500ksps throughput, ultra-low shutdown current (14µA), and OVDD-level shifting - making it optimal for space-constrained, battery-sensitive, and isolated high-precision applications where alternatives trade off accuracy, power, or interface flexibility.

Availability

LTC2302CDD#TRPBF is available at Aetrix Electronics and suitable for industrial process monitoring, battery-powered sensor nodes, and isolated data acquisition requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LTC2302CDD#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 (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC2302 belongs to Linear's precision SAR ADC product line, designed specifically for applications demanding low noise, guaranteed monotonicity, and low-power operation in harsh or size-constrained environments - such as portable instrumentation and distributed sensing.

FAQ

What is the operating temperature range for the LTC2302CDD#TRPBF?

The LTC2302CDD#TRPBF is specified for 0°C to 70°C ambient operation, as indicated by the "C" grade suffix in its part number. This commercial-grade rating suits indoor industrial equipment, test instruments, and consumer-grade portable devices where ambient temperatures remain within this range. The device features thermal protection with TJMAX = 150°C and θJA = 43°C/W, requiring proper PCB copper area under the exposed pad for reliable operation at full throughput.

Does the LTC2302CDD#TRPBF support single-ended input configurations?

No, the LTC2302CDD#TRPBF does not support true single-ended inputs. Its analog inputs (IN+, IN–) are strictly differential - meaning it measures the voltage difference between these two pins. However, it supports unipolar (0–4.096V) and bipolar (±2.048V) differential ranges via software configuration. For single-ended sources, an external differential driver (e.g., op-amp configured as subtractor) is required to convert the signal to differential format before connecting to IN+/IN–.

How does the auto-shutdown feature work in the LTC2302CDD#TRPBF?

The LTC2302CDD#TRPBF automatically scales supply current based on sampling rate: it draws 2.8mA at 500ksps, drops to ~7µA at 1ksps, and reaches 14µA in sleep mode (no conversions). This is achieved by internally gating clock distribution and bias currents - no external control signal is needed. The feature is transparent to the user and activates dynamically as the CONVST trigger frequency changes, making it ideal for burst-mode sensing without firmware intervention.

Can the LTC2302CDD#TRPBF use the same reference for both VREF and VDD?

Yes - if the reference voltage is 5V and can source ≥5mA (e.g., LT6660-5), it may power both VDD and VREF. However, this requires careful layout: VDD must be heavily decoupled (0.1µF ceramic + 10µF tantalum) directly at the pin, and VREF must use identical decoupling (10µF + 0.1µF) to prevent noise coupling. In practice, dedicated low-noise references like LT1790A-4.096 are preferred for VREF to maximize SINAD, while VDD is supplied from a clean 5V LDO.

What is the minimum acquisition time required for full 12-bit accuracy with the LTC2302CDD#TRPBF?

The LTC2302CDD#TRPBF requires a minimum 240ns acquisition time (tACQ) after the 7th SCK rising edge and before the next CONVST rising edge. This interval allows the internal 55pF sample-and-hold capacitor to settle to 12-bit accuracy (1/2 LSB = 0.5 × VREF/4096). Driving sources with >1kΩ impedance may require longer settling; RC filters must be designed so τ ≤ tACQ/3 (~80ns) to avoid gain error - e.g., R ≤ 1.5kΩ with C ≤ 55pF.