Analog Devices Inc. DC2085A-A

Overview

DC2085A-A from Analog Devices (formerly Linear Technology) is a demonstration circuit board designed specifically to evaluate the LTC2000IY-16, a 16-bit, 2.5 Gsps high-speed DAC with differential DC-coupled outputs. It supports analog output frequencies from DC to 1000 MHz, operates from a 4.8–5.2 V supply delivering up to 800 mA, and interfaces via LVDS digital inputs and SMA-triggered sample clock input at up to 15 dBm.

For engineers reviewing the DC2085A-A datasheet, DC2085A-A pinout, DC2085A-A application, or DC2085A-A equivalent, this page delivers verified hardware interface details, FPGA-driven waveform generation support via LTDACGen software, HSMC-based connection to Altera Stratix IV development boards, and analog output network design optimized for SFDR performance in RF signal synthesis and wideband test equipment.

Technical Context

The DC2085A-A implements a complete evaluation platform for the LTC2000-16 DAC, featuring an onboard LT8614 buck regulator, LTC6655 precision voltage reference, and dual LT3080 low-noise LDOs for AVDD1V8 and DVDD1V8 rails. Its analog output stage uses matched 50 Ω resistive termination per side plus a π-network to achieve 50 Ω single-ended impedance when driving external baluns.

Digital interface relies on two 16-bit LVDS data buses (DA[0:15], DB[0:15]), differential trigger inputs (J2/J3), and a single-ended 50 Ω sample clock input (J4) with internal balun conversion. Power sequencing is managed through turrets (+5V, SVDD3V0, AVDD3V3, DVDD3V3, AVDD1V8, DVDD1V8) and jumpers (JP1 for RUN/SHDN, JP2 for SPI/JTAG).

Key Specifications

Availability

DC2085A-A is available at Aetrix Electronics and suitable for RF test equipment, wideband communications transceivers, radar waveform synthesis, and high-speed data converter validation requiring stable component supply and full technical documentation.

Supply support for DC2085A-A 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, acquired Linear Technology in 2017 to strengthen its precision and high-speed data converter portfolio.

The DC2085A-A belongs to ADI's demonstration circuit product line, engineered to accelerate evaluation of ultra-high-speed DACs in demanding RF and instrumentation applications where signal fidelity, phase noise, and wideband spectral purity are critical.

FAQ

What DAC does the DC2085A-A evaluate?

The DC2085A-A evaluates the LTC2000IY-16 - a 16-bit, 2.5 Gsps current-output DAC in a 144-lead LQFP package. It is not compatible with LTC2000A variants (e.g., DC2085A-D), which require different clocking and power configurations. The board's schematic and assembly table explicitly designate U1 as LTC2000IY-16 for DC2085A-A.

Does DC2085A-A support differential sample clock input?

No - DC2085A-A accepts only single-ended sample clock input at SMA connector J4. An onboard balun converts it to differential for the LTC2000IY-16. The demo manual specifies "default is a single-ended 50Ω input port" and confirms no provision for direct differential clock injection on this variant.

Can DC2085A-A be powered solely from the Altera Stratix IV board?

No - DC2085A-A requires external +5 V applied to the +5V turret (not via HSMC). The Stratix IV supplies only digital I/O voltage and configuration data over HSMC; the DAC's analog and digital power rails (including 1.8 V AVDD/DVDD) are derived from the DC2085A-A's own regulators fed by the +5 V input.

What software is required to operate DC2085A-A?

LTDACGen software - a free Windows application provided by Analog Devices - is required to configure the FPGA, load waveforms, and control the LTC2000IY-16 via the onboard FT2232HL USB-to-FIFO bridge (U2). It communicates directly with DC2085A-A through J7 (USB-B) and supports real-time waveform updates and register-level DAC control.

How is analog output impedance configured on DC2085A-A?

DC2085A-A presents 50 Ω per side (100 Ω differential) at SMA connectors J5 and J6. This is achieved using dual 50 Ω terminations driven by the DAC plus a π-network of 50 Ω resistors - enabling direct connection to 50 Ω spectrum analyzers via external baluns without impedance mismatch penalties.