Texas Instruments ADS8320EB/250

Overview

ADS8320EB/250 from Texas Instruments is a 16-bit successive approximation register (SAR) analog-to-digital converter optimized for high-precision, low-power data acquisition. It delivers 100-kHz throughput, ±0.006% integral linearity error (FSR), and 92-dB SNR at 5 V supply, operating from 2.7 V to 5.25 V with differential inputs (+In/–In) and external reference scaling (0.5 V to V_CC). It serves in battery-powered remote sensing and isolated industrial measurement systems.

For engineers reviewing the ADS8320EB/250 datasheet, ADS8320EB/250 pinout, ADS8320EB/250 application, or ADS8320EB/250 equivalent, this page provides verified technical context, validated pin functions, confirmed performance parameters across voltage and temperature ranges, and real-world implementation constraints - including clock timing margins, reference current dependency on sample rate, and differential input voltage limits.

Technical Context

The ADS8320EB/250 implements a capacitive redistribution SAR architecture with integrated sample-and-hold, fabricated in 0.6-µm CMOS. Conversion is initiated by CS/SHDN falling edge, followed by 4.5-cycle acquisition and 16-cycle conversion, synchronized to DCLOCK with data output on DOUT starting after the fifth falling edge.

It supports SPI/SSI-compatible 3-wire serial interface (CS/SHDN, DCLOCK, DOUT), straight-binary 16-bit output, and operates with external reference (0.5 V to V_CC) and external clock (24 kHz to 2.4 MHz). Input common-mode range is constrained: –In limited to –0.1 V to 0.5 V at 2.7 V supply, requiring careful grounding for differential rejection.

Key Specifications

Pinout & Package

ADS8320EB/250 is housed in an 8-pin VSSOP package (3.00 mm × 3.00 mm body), thermally rated for R_θJA = 163.1°C/W. Pin functions are validated per TI SBAS108E Rev E (December 2016).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8320EB/250, ADS8320E/250 trades 0.002% INL and 2-dB SNR for lower cost, while ADS8321EB/250 extends resolution to 18 bits at the expense of throughput and power - making ADS8320EB/250 the optimal balance of speed, precision, and efficiency for 16-bit embedded DAQ.

Availability

ADS8320EB/250 is available at Aetrix Electronics and suitable for battery-operated remote sensors, isolated industrial data acquisition modules, and simultaneous multi-channel sampling systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for ADS8320EB/250 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 over 50 years of innovation in precision data converters and power management ICs.

The ADS8320EB/250 belongs to TI's precision SAR ADC product line, engineered for high-resolution, low-power data acquisition in portable, isolated, and multi-channel industrial systems - emphasizing accuracy retention across voltage and temperature extremes.

FAQ

What is the maximum clock frequency supported by ADS8320EB/250 at 2.7 V supply?

The ADS8320EB/250 supports a maximum DCLOCK frequency of 2.4 MHz at 2.7 V supply, enabling its full 100-kHz throughput rate. At lower sample rates, clock frequency may be reduced proportionally; however, minimum clock period remains constrained by internal capacitor leakage - below 24 kHz, acquisition time degrades due to charge loss on the sampling array. The ADS8320EB/250 datasheet specifies timing margins (e.g., t_SUCS = 20 ns) that must be met regardless of V_CC.

Can ADS8320EB/250 operate with a 0.5-V reference voltage, and what impact does that have on noise performance?

Yes, ADS8320EB/250 supports V_REF as low as 0.5 V, but doing so reduces LSB size to ~7.6 µV and amplifies the effect of internal noise - increasing peak-to-peak noise contribution from ~1.5 LSB (at 5 V) to ~15 LSB. To maintain accuracy, the reference and analog input must each exhibit <50 µV peak-to-peak noise, and layout must include tight bypassing, ground isolation, and shielding. The ADS8320EB/250 reference current also rises to 80 µA at high sample rates, demanding low-impedance reference buffering.

How does the –In pin function in differential mode, and what are its voltage limitations?

In ADS8320EB/250, the –In pin is sampled simultaneously with +In during acquisition and held constant for conversion - it is not resampled later. Its voltage range is strictly limited: –0.1 V to 0.5 V when V_CC = 2.7 V, and –0.1 V to 1 V at higher supplies. This restricts true differential operation to small common-mode offsets, making –In best suited for remote ground sensing rather than full-rail differential signaling. Exceeding these limits risks linearity degradation and potential damage per absolute maximum ratings.

Is ADS8320EB/250 compatible with 5-V logic systems when powered from 3.3 V?

Yes, ADS8320EB/250 digital inputs (CS/SHDN, DCLOCK) tolerate up to 5.5 V regardless of V_CC, allowing direct connection to 5-V microcontrollers. However, its DOUT output swings 0 V to V_CC (i.e., 0–3.3 V), which may fall below the VIH threshold of some 5-V CMOS receivers. In such cases, a level-shifter or pull-up resistor is required. The ADS8320EB/250 datasheet confirms this I/O voltage tolerance in Section 7.4.1.

What is the significance of the "EB" suffix in ADS8320EB/250, and how does it differ from the base ADS8320?

The "EB" suffix denotes the enhanced performance grade of ADS8320EB/250: it guarantees ±0.006% integral linearity error (vs. ±0.008% for ADS8320E), 92-dB SNR (vs. 90 dB), and 15-bit no-missing-codes performance (vs. 14-bit). These tighter specifications are achieved through post-package trimming and screening. The ADS8320EB/250 shares identical pinout, timing, and functional behavior with ADS8320E/250, making it a direct upgrade path where higher precision is required.