Analog Devices Inc. LTC2151IUJ-12#PBF

Overview

LTC2151IUJ-12#PBF from Analog Devices (formerly Linear Technology) is a 12-bit, 210Msps high-speed analog-to-digital converter optimized for undersampling wideband RF signals in communications infrastructure. It delivers 68.5dB SNR, 90dB SFDR, and 1.25GHz full-power bandwidth with DDR LVDS outputs, operating from a single 1.8V supply and supporting low-power Nap (99mW) and Sleep (<2mW) modes. It is used in cellular basestations and software-defined radios requiring high dynamic range at IF frequencies up to 907MHz.

For engineers reviewing the LTC2151IUJ-12#PBF datasheet, LTC2151IUJ-12#PBF pinout, LTC2151IUJ-12#PBF application, or LTC2151IUJ-12#PBF equivalent, key selection criteria include its 210Msps sampling rate, differential 1.5VP-P input range, ±0.30LSB INL, 40-lead QFN package, and SPI-configurable clock duty cycle stabilizer - all critical for RF receiver front-end digitization where jitter, linearity, and power efficiency are tightly coupled.

Technical Context

The LTC2151IUJ-12#PBF employs a 12-bit pipelined ADC architecture with integrated sample-and-hold (S/H) featuring 1.25GHz full-power bandwidth and 0.15psRMS aperture jitter. Its digital interface uses double-data-rate (DDR) LVDS outputs with programmable 1.75mA/3.5mA current drive and optional on-chip 100Ω termination per pair.

Configuration is performed via a 3-wire SPI port (CS/SCK/SDI/SDO), supporting serial or parallel programming modes selected by the PAR/SER pin. The device includes an internal reference (1.25V VREF, 0.439•VDD VCM) and supports external reference operation via the SENSE pin, enabling flexible ±0.6•VSENSE input scaling.

Key Specifications

Pinout & Package

40-lead (6mm × 6mm) plastic QFN package with exposed thermal pad (Pin 41 = GND), requiring soldering to PCB ground plane for thermal and electrical integrity. Pin pitch: 0.5mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9230-210EBZ and LTC2261IUJ-12#PBF, the LTC2151IUJ-12#PBF uniquely balances 210Msps speed, 90dB SFDR, and 333mW power in a pin-compatible family with configurable duty cycle stabilization - making it optimal for RF receivers where jitter-limited SFDR and thermal density are co-constrained.

Availability

LTC2151IUJ-12#PBF is available at Aetrix Electronics and suitable for cellular basestations, software-defined radios, medical ultrasound systems, and test equipment requiring stable component supply across industrial temperature ranges (–40°C to +85°C).

Supply support for LTC2151IUJ-12#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 RF ICs, serving precision instrumentation, communications, and industrial markets.

The LTC215x-12 family was designed specifically for high-dynamic-range undersampling in wireless infrastructure and defense electronics, emphasizing jitter immunity, wide input bandwidth, and low-power operational modes without sacrificing DC accuracy.

FAQ

What is the maximum sampling rate supported by the LTC2151IUJ-12#PBF?

The LTC2151IUJ-12#PBF supports a maximum sampling rate of 210Msps, as specified in its part number suffix and confirmed in the datasheet's timing characteristics table. This rate is guaranteed over the full industrial temperature range (–40°C to +85°C) with proper power supply decoupling and clock signal integrity. Operation above this rate is not characterized and may result in degraded SNR or missing codes.

Does the LTC2151IUJ-12#PBF require an external reference voltage?

No, the LTC2151IUJ-12#PBF includes an internal 1.25V reference (VREF) and common-mode bias (VCM = 0.439•VDD) that are fully functional without external components. An external reference between 1.2V and 1.3V can be applied to the SENSE pin to configure a scaled ±0.6•VSENSE input range, but it is optional - the default internal reference enables immediate operation with a 1.5VP-P differential input.

How does the clock duty cycle stabilizer function in the LTC2151IUJ-12#PBF?

The clock duty cycle stabilizer in the LTC2151IUJ-12#PBF is an on-chip circuit that reshapes asymmetric ENC+/ENC– inputs into a near-50% duty cycle clock internally, reducing aperture jitter sensitivity. It is enabled via the SPI register or parallel CS pin and maintains <0.15psRMS jitter even with input duty cycles from 30% to 70%, which is critical for preserving SFDR at full 210Msps sampling.

What are the power consumption modes available on the LTC2151IUJ-12#PBF?

The LTC2151IUJ-12#PBF offers three operational power states: Active mode (333mW at 210Msps), Nap mode (99mW, retains configuration and fast wake-up), and Sleep mode (<2mW, minimal current draw with full register retention). These are controlled via SPI or parallel logic inputs (SCK/CS), enabling dynamic power scaling in burst-mode or battery-operated systems without reconfiguration overhead.

Is the LTC2151IUJ-12#PBF pin-compatible with other members of the LTC215x-12 family?

Yes, the LTC2151IUJ-12#PBF shares identical 40-lead QFN packaging, pinout, and footprint with the LTC2152-12 (250Msps) and LTC2150-12 (170Msps), enabling drop-in replacement across sampling rates. All variants support the same SPI interface, LVDS output structure, and feature set - only the maximum sampling rate and corresponding power/SFDR specifications differ.