Texas Instruments THS0842EVM

Overview

THS0842EVM from Texas Instruments is an evaluation module designed to characterize the THS0842 10-bit, 80-MSPS dual-channel analog-to-digital converter under real-world signal, reference, and supply conditions. It supports differential and single-ended transformer-coupled analog inputs, onboard or external 80-MHz clocking, dual 10-bit DAC-based analog reconstruction (THS5651A), and TTL-compatible digital output via 26-pin IDC headers.

For engineers reviewing the THS0842EVM datasheet, THS0842EVM pinout, THS0842EVM application, or THS0842EVM equivalent, this page provides verified functional architecture, jumper-configurable signal paths (I/Q channels, reference selection, clock source), power domain isolation (3.3-V AVDD/DVDD/DRVDD), and interface-level design guidance for high-speed data acquisition validation.

Technical Context

The THS0842EVM implements a complete signal chain around the THS0842 ADC: analog input conditioning via SMB connectors (J8–J13) with selectable transformer-coupled or direct differential paths; clock distribution using either an onboard 80-MHz crystal oscillator (X1) or external LVTTL source (J4); and dual-channel digital output buffering through SN74LVC827A octal bus transceivers (U1/U2/U4/U5/U7/U9/U12).

Analog output reconstruction uses two THS5651A 10-bit, 125-MHz DACs (U3/U6) synchronized to COUT/COUT clocks, generating I/Q waveforms on SMB connectors J1 and J3. Power is segregated into independent analog (J6), digital (J7), and driver (DRVDD) rails, with decoupling per TI's high-speed layout guidelines - including 10-µF tantalum and 0.1-µF ceramic capacitors at each supply pin.

Key Specifications

Availability

THS0842EVM is available at Aetrix Electronics and suitable for high-speed data acquisition, communications receiver testing, radar waveform validation, and mixed-signal system prototyping requiring stable component supply and documented evaluation infrastructure.

Supply support for THS0842EVM 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and high-performance signal chain solutions, with decades of expertise in data converters and evaluation platforms.

The THS0842EVM belongs to TI's precision high-speed ADC evaluation ecosystem, engineered to accelerate validation of RF-sampling and quadrature receiver architectures using the THS0842 dual-channel ADC.

FAQ

What is the primary function of the THS0842EVM?

The THS0842EVM is a dedicated evaluation platform for the THS0842 10-bit, 80-MSPS dual-channel ADC. It enables engineers to validate performance under configurable analog input modes (differential or transformer-coupled), clock sources (onboard 80-MHz oscillator or external), reference configurations (internal or external), and output formats (digital parallel or reconstructed analog I/Q). The THS0842EVM includes all necessary signal conditioning, buffering, and power isolation to replicate real-world deployment conditions for the THS0842.

How do I configure the THS0842EVM for external clock operation?

To use an external clock with the THS0842EVM, ensure jumper W6 is removed (open) to disable the onboard oscillator path, and apply a 50-Ω-terminated 3.3-V LVTTL square wave to SMB connector J4. The default shipping configuration has W6 open and W3 shorted, making external clock the active mode. Verify that jumpers W12–W15 are set to positions 2–3 for single-ended input or 1–2 for differential input, depending on your signal source. The THS0842EVM will synchronize conversion to the applied clock edge without additional setup.

Can the THS0842EVM generate analog output signals?

Yes - the THS0842EVM reconstructs analog I/Q waveforms using two THS5651IDW 10-bit DACs (U3 and U6). Analog outputs appear on SMB connectors J1 (I-output) and J3 (Q-output), but only when jumper W8 is installed to enable dual-bus mode and SELB is held low. The DACs latch THS0842 digital output on COUT (Q-DAC) or /COUT (I-DAC) edges. This feature allows closed-loop verification of ADC+DAC signal integrity, critical for quadrature receiver development using the THS0842EVM.

What power supplies are required for proper THS0842EVM operation?

The THS0842EVM requires three independent 3.3-V supplies: analog (AVDD, connected to J6–1), digital (DVDD, connected to J7–1), and driver (DRVDD, derived internally but sensitive to AVDD/DVDD stability). Each supply must be low-noise and well-decoupled; TI recommends separate analog/digital ground planes spliced near U11 (THS0842). Exceeding 3.3 V risks component damage, while undervoltage causes erratic sampling or logic failure. The THS0842EVM does not regulate input voltage - strict adherence to 3.3 V ±5% is mandatory for valid THS0842 characterization.

How are analog input ranges adjusted on the THS0842EVM?

Analog input range on the THS0842EVM is set by the voltage difference between REFT and REFB pins of the THS0842. With internal reference (W4 installed), full-scale range is 1.0 Vpp at AVDD = 3.3 V. To extend it to 1.3 Vpp, remove W4 and apply external references - e.g., 2.1 V to REFT and 0.8 V to REFB, per Table 2–3 in the user's guide. These voltages must be derived from precision bandgap references (e.g., TL1431CD on the board), not resistive dividers, to maintain THS0842 linearity and SNR during evaluation.