Texas Instruments ADS825E

Overview

ADS825E from Texas Instruments is a 10-bit, 40MSPS pipelined analog-to-digital converter (ADC) designed for high-fidelity signal acquisition in demanding imaging and instrumentation systems. It operates from a single +5V supply, supports both single-ended and fully differential analog inputs, and delivers 60dB SNR and 72dBFS SFDR at 1MHz input - key for medical imaging front-ends and video digitizing.

For engineers reviewing the ADS825E datasheet, ADS825E pinout, ADS825E application, or ADS825E equivalent, this page provides verified technical context, SSOP-28 package mapping, confirmed +3V/+5V logic I/O compatibility, power-down mode (20mW), and real-world interface constraints including aperture jitter (1.2ps rms) and 5-cycle data latency.

Technical Context

The ADS825E employs a 9-stage pipelined CMOS architecture with digital error correction logic to guarantee no missing codes and ±0.5LSB DNL across temperature. Its track-and-hold accepts either 1V_p-p or 2V_p-p full-scale ranges via RSEL pin control and supports internal reference (±1.5% gain error) or external reference (REFB/REFT pins) for multichannel gain matching.

It samples on the rising edge of CLK with 3ns aperture delay and 12.5ns minimum clock pulse width; the VDRV pin enables independent 3V or 5V logic driver supply, directly supporting TTL or CMOS interfaces without level shifters. Input common-mode voltage is fixed at +2.5V (CM pin), and analog input bandwidth exceeds 300MHz in track mode.

Key Specifications

Pinout & Package

ADS825E is housed in a 28-pin SSOP (Shrink Small Outline Package) with 0.65mm pitch, JEDEC MO-153 compliant, thermal resistance θ_JA = 89°C/W. Pin 1 is GND; pin 28 is VDRV; pins 2–11 are D9–D0 (MSB to LSB); pins 24–25 are complementary analog inputs (IN, IN); pin 23 is CM (common-mode output).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed 10-bit ADC applications.

Compared with ADS825E, ADS823E offers higher speed at same power and pin compatibility, while ADS828E trades increased power and layout sensitivity for superior SFDR and bandwidth - neither is drop-in replaceable without clock and thermal redesign.

Availability

ADS825E is available at Aetrix Electronics and suitable for medical imaging front-ends, communications IF digitizers, and computer scanner image sensor interfaces requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for ADS825E 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 connectivity technologies, with decades of expertise in precision data converters and signal chain solutions.

The ADS82x family was engineered for high-fidelity, medium-speed digitization in imaging, instrumentation, and communications - emphasizing spurious-free dynamic range, flexible reference architecture, and single-supply operation.

FAQ

What is the maximum input frequency the ADS825E can accurately sample?

The ADS825E has a track-mode analog input bandwidth of 300MHz (–3dB), enabling accurate sampling of signals well beyond its 40MSPS Nyquist limit. When used in undersampling mode, it reliably captures 75MHz IF signals with 59dBFS SNR and 66dBFS SFDR, as verified in TI's SBAS069B datasheet Figure 6. The ADS825E's 1.2ps rms aperture jitter ensures minimal SNR degradation even at high input frequencies.

Does the ADS825E support differential input configuration?

Yes, the ADS825E supports fully differential analog inputs via pins 24 (IN) and 25 (IN), with common-mode bias provided by the CM pin (+2.5V). In differential mode, it achieves 74dBFS SFDR at 10MHz - 3dB higher than single-ended - due to common-mode noise rejection and matched internal capacitance. The ADS825E's datasheet confirms differential operation in Figures 1 and 5, including transformer-coupled interface guidance.

What logic levels are compatible with the ADS825E digital interface?

The ADS825E accepts +3V or +5V logic levels on all digital inputs (CLK, OE, PD, RSEL, INT/EXT) and supports corresponding output swings via the VDRV pin. With VDRV = 3V, outputs drive 0.1V low and 2.8V high; with VDRV = 5V, they drive 0.1V low and 4.9V high - matching TTL and CMOS families without external buffers. This dual-voltage capability is explicitly stated in the "DIGITAL INPUTS" table of SBAS069B.

How does the ADS825E handle power management in portable applications?

The ADS825E features an active-HI PD (Power Down) pin that reduces total power dissipation from 190mW to 20mW while preserving register state and enabling fast wake-up (<100ns). This mode disables the analog core and track-and-hold but keeps digital logic ready - ideal for battery-powered test equipment or handheld medical scanners where duty cycling is essential. The ADS825E's power-down behavior is characterized in Section "POWER-SUPPLY REQUIREMENTS" of SBAS069B.

Can the ADS825E use an external reference, and what are the voltage limits?

Yes, the ADS825E supports external references via REFT and REFB pins when INT/EXT is set HIGH. External REFT must be between (V_S – 1.25V) and (REFB + 0.8V); external REFB must be between 1.25V and (REFT – 0.8V). For +5V supply, this permits REFT from 3.75V to 4.3V and REFB from 1.25V to 2.2V - enabling precise full-scale adjustment and multichannel gain matching. These limits are specified in Note 9 and Table "ELECTRICAL CHARACTERISTICS" of SBAS069B.