Analog Devices Inc. LTC2306CDD#PBF

Overview

LTC2306CDD#PBF from Analog Devices (formerly Linear Technology) is a 2-channel, 12-bit successive approximation register (SAR) ADC with SPI/MICROWIRE-compatible serial interface, 500ksps sampling rate, 72.8dB SINAD, and fully differential sample-and-hold circuitry. It operates from a single 5V supply, draws 2.8mA at full speed, and supports software-selectable unipolar (0V to 4.096V) or bipolar (±2.048V) input ranges - ideal for precision industrial sensor data acquisition.

For engineers reviewing the LTC2306CDD#PBF datasheet, LTC2306CDD#PBF pinout, LTC2306CDD#PBF application, or LTC2306CDD#PBF equivalent, key selection considerations include its 10-pin DFN package, channel-to-channel isolation of –109dB, internal conversion clock enabling SCK up to 40MHz, separate OVDD rail (2.7V–5.25V), and guaranteed no missing codes over temperature.

Technical Context

The LTC2306CDD#PBF implements a capacitive charge-redistribution SAR architecture with a 12-bit internal DAC and differential comparator. Its analog input multiplexer supports dynamic reconfiguration between single-ended (CH0/GND, CH1/GND) and differential (CH0/CH1) modes via 6-bit SDI command words, with O/S and S/D bits controlling channel assignment and polarity.

Conversion timing is governed by an internal clock; CONVST rising edge initiates acquisition (min 240ns), followed by 1.3–1.6µs conversion time. Serial output on SDO occurs on SCK falling edges, with tACQ, tCONV, and tdDO tightly specified to support deterministic real-time control loops in motor or power electronics systems.

Key Specifications

Pinout & Package

Package: 10-lead (3mm × 3mm) plastic DFN with exposed pad (Pin 11 = GND). Requires soldering exposed pad 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 ADS8860IDRCT and MAX11106ETE+, the LTC2306CDD#PBF uniquely balances dual-channel correlation, SPI compatibility, ultra-low power scaling, and software-selectable input ranges - making it optimal for space-constrained, battery-aware, or isolated industrial data loggers requiring deterministic timing.

Availability

LTC2306CDD#PBF is available at Aetrix Electronics and suitable for industrial process control, motor control feedback, and battery-operated instrumentation requiring stable component supply and long-term production continuity.

Supply support for LTC2306CDD#PBF 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. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors.

The LTC2306CDD#PBF belongs to Linear's precision SAR ADC product line, designed specifically for demanding industrial, instrumentation, and medical applications where low noise, guaranteed monotonicity, and robust serial interfacing are essential.

FAQ

What input configurations does the LTC2306CDD#PBF support?

The LTC2306CDD#PBF supports four analog input configurations via its 6-bit SDI command: single-ended CH0 vs GND, single-ended CH1 vs GND, differential CH0–CH1, and differential CH1–CH0. The S/D bit selects single-ended/differential mode, and the O/S bit selects channel order or polarity. Unipolar mode (0V to 4.096V) is required for single-ended operation since inputs are referenced to GND. The LTC2306CDD#PBF's internal MUX enables reconfiguration "on the fly" between conversions without hardware changes.

Does the LTC2306CDD#PBF require an external reference, and what are the voltage limits?

Yes, the LTC2306CDD#PBF requires an external reference connected to the VREF pin, with a valid range of 0.1V to VDD (5V). Typical use cases employ 4.096V references (e.g., LT6660-4.096) to achieve full 12-bit utilization. The reference input draws up to 260µA at 500ksps and must be decoupled with a minimum 10µF tantalum capacitor in parallel with a 0.1µF ceramic capacitor. The LTC2306CDD#PBF does not include an internal reference, so external stability and noise performance directly impact overall accuracy and SINAD.

How does the auto-shutdown feature of the LTC2306CDD#PBF reduce power consumption?

The LTC2306CDD#PBF's auto-shutdown feature dynamically scales supply current with sampling rate: it draws 2.8mA at 500ksps, drops to ~15µA at 1ksps, and enters 70µW sleep mode when idle. This occurs automatically based on CONVST activity - no software commands or register writes are needed. The LTC2306CDD#PBF achieves this through internal clock gating and bias current adjustment, eliminating external power-switching circuitry and reducing system-level complexity in battery-powered or energy-conscious designs.

Can the LTC2306CDD#PBF interface directly with a 3.3V microcontroller?

Yes, the LTC2306CDD#PBF supports direct interfacing with 3.3V microcontrollers using its separate OVDD pin (2.7V–5.25V range). When OVDD = 3.3V, the SDO output swings between 0V and 3.3V, matching standard 3.3V logic levels. The SDI, SCK, and CONVST inputs tolerate voltages up to VDD (5V) and meet 3.3V logic thresholds (VIH = 2.4V min, VIL = 0.8V max), allowing reliable communication without level shifters. The LTC2306CDD#PBF's dual-supply architecture simplifies mixed-voltage system integration.

What is the significance of the –109dB channel-to-channel isolation specification for the LTC2306CDD#PBF?

The –109dB channel-to-channel isolation specification means that a full-scale signal on CH0 produces less than 0.0003% of its amplitude on CH1 (and vice versa), measured at 1kHz. This exceptional isolation is achieved through matched internal switch capacitance and guard routing in the 10-pin DFN package. For the LTC2306CDD#PBF, this enables accurate simultaneous sampling of high- and low-level signals - such as motor phase currents and DC bus voltage - without mutual interference, critical for vector control algorithms and safety-critical monitoring.