Analog Devices Inc. LTC2246CUH#PBF

Overview

LTC2246CUH#PBF from Analog Devices (formerly Linear Technology) is a 14-bit, 25Msps low-power pipelined analog-to-digital converter operating from a single 3V supply. It delivers 74.5dB SNR and 90dB SFDR at 5MHz input, features ±1LSB INL and ±0.5LSB DNL, and supports flexible ±0.5V to ±1V differential input ranges - ideal for portable ultrasound front-ends and spectral analysis instrumentation.

For engineers reviewing the LTC2246CUH#PBF datasheet, LTC2246CUH#PBF pinout, LTC2246CUH#PBF application, or LTC2246CUH#PBF equivalent, key selection criteria include its 25Msps sampling rate, 575MHz full-power bandwidth, clock duty cycle stabilizer, shutdown/nap modes, and QFN-32 package compatibility with signal integrity-critical RF and medical data acquisition systems.

Technical Context

The LTC2246CUH#PBF implements a six-stage CMOS pipelined ADC architecture with digital correction logic, achieving 5-cycle pipeline latency. Its sample-and-hold uses differential NMOS-switched 4pF sampling capacitors and supports both internal (1.5V VCM) and external reference configurations via SENSE and MODE pins.

It operates with a single-ended CLK input and provides offset binary or 2's complement output formats. The clock duty cycle stabilizer enables high AC performance across wide duty cycle ranges (5%–95%), while OF (over/underflow) and SHDN/OE pins support real-time data integrity monitoring and power management in battery-constrained embedded systems.

Key Specifications

Pinout & Package

The LTC2246CUH#PBF is housed in a 32-pin, 5mm × 5mm plastic QFN package with exposed thermal pad (Pin 33 = GND). The package requires soldering of the exposed pad to PCB ground for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-linearity, low-power ADC applications.

Compared with ADS8860IDRCT and AD9245BSTZ-25, the LTC2246CUH#PBF uniquely balances 25Msps throughput, 90dB SFDR, and 75mW power in a compact QFN-32 - making it optimal for portable, wideband, battery-operated instrumentation where spurious-free dynamic range directly impacts diagnostic confidence.

Availability

LTC2246CUH#PBF is available at Aetrix Electronics and suitable for portable medical diagnostics, spectral analysis instrumentation, and ultrasound imaging front-ends requiring stable component supply across extended product lifecycles.

Supply support for LTC2246CUH#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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2246CUH#PBF belongs to ADI's legacy Linear Technology high-speed precision ADC family, engineered specifically for demanding medical imaging, test equipment, and communications infrastructure where dynamic range, low power, and small footprint are co-primary constraints.

FAQ

What is the maximum input frequency supported by the LTC2246CUH#PBF before SNR degrades below 70dB?

The LTC2246CUH#PBF maintains ≥70dB SNR up to 140MHz input frequency (73.0dB at 140MHz, 2V range, –1dBFS). Its 575MHz full-power bandwidth ensures minimal amplitude attenuation, though SNR rolls off gradually above 70MHz due to thermal and quantization noise dominance - verified per Figure 2246 G09 in the datasheet.

Does the LTC2246CUH#PBF require external reference components, or can it operate with internal references only?

The LTC2246CUH#PBF supports both internal and external reference operation. With SENSE tied to VCM, it uses the internal 1.5V reference for ±0.5V input range; with SENSE tied to VDD, it configures for ±1V range. External references >0.5V and <1V applied to SENSE scale the input range linearly - no external reference IC is required for standard operation.

How does the clock duty cycle stabilizer in the LTC2246CUH#PBF improve system design flexibility?

The clock duty cycle stabilizer in the LTC2246CUH#PBF allows reliable operation with CLK duty cycles from 5% to 95%, eliminating need for precision clock buffers or duty cycle correction circuits. This reduces BOM cost and layout complexity - especially valuable when deriving clocks from microcontrollers or PLLs with variable duty cycle tolerance.

Can the LTC2246CUH#PBF interface directly with a 1.8V FPGA I/O bank without level-shifting?

Yes. The LTC2246CUH#PBF's OVDD pin accepts 0.5V to 3.6V, and its digital outputs are fully specified at OVDD = 1.8V (VOH ≥ 1.79V, VOL ≤ 0.09V, IO = ±200µA). This enables direct connection to 1.8V FPGA I/O banks without external level shifters - confirmed in Table 4 of the datasheet under "LOGIC OUTPUTS".

What is the thermal pad connection requirement for the LTC2246CUH#PBF QFN package?

The exposed thermal pad (Pin 33) of the LTC2246CUH#PBF must be soldered to a solid PCB ground plane. Per datasheet Section "PACKAGE/ORDER INFORMATION", this connection is mandatory for thermal dissipation (θJA = 34°C/W) and electrical stability - floating or unterminated pads cause degraded SNR, increased jitter, and potential reliability failure.