Analog Devices Inc. AD7893BR-10

Overview

AD7893BR-10 from Analog Devices is a 12-bit successive-approximation ADC with ±10 V analog input range, 6 µs conversion time, on-chip track/hold amplifier, and high-speed two-wire serial interface (SCLK/SDATA), operating from a single +5 V supply in an 8-pin SOIC package for industrial data acquisition systems.

For engineers reviewing the AD7893BR-10 datasheet, AD7893BR-10 pinout, AD7893BR-10 application, or AD7893BR-10 equivalent, this page delivers verified technical context, real-world timing constraints, confirmed input scaling behavior, and validated alternative options for ±10 V bipolar signal digitization in space-constrained embedded designs.

Technical Context

The AD7893BR-10 implements a laser-trimmed internal clock driving a 12-bit R-2R ladder SAR core, with integrated track/hold acquiring to ±1/2 LSB in ≤1.5 µs. Its analog front-end scales ±10 V inputs using on-chip resistor networks (R1=30 kΩ, R2=7.5 kΩ, R3=10 kΩ) referenced to a buffered 2.5 V external reference.

Serial output delivers 16-bit frames: four leading zeros followed by 12-bit twos-complement data (MSB first), valid on SCLK falling edges; SDATA three-states after the 16th falling edge. No BUSY or EOC pin exists - timing coordination relies strictly on CONVST edge control and fixed 6 µs conversion latency.

Key Specifications

Pinout & Package

AD7893BR-10 is housed in an 8-pin SOIC (SO-8) package with 1.27 mm pitch, JEDEC MS-012AC compliant, rated for –40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit serial ADC applications.

Compared with AD7893AR-10 and ADS7822U, the AD7893BR-10 provides the tightest DC accuracy (±1/2 LSB), fastest conversion (6 µs), and fully integrated track/hold - making it optimal for high-fidelity, space-constrained industrial DAQ where timing determinism and bipolar ±10 V support are mandatory.

Availability

AD7893BR-10 is available at Aetrix Electronics and suitable for industrial process monitoring, portable test equipment, motor drive current sensing, and automated calibration systems requiring stable component supply across extended temperature ranges.

Supply support for AD7893BR-10 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, founded in 1965 and headquartered in Wilmington, MA.

The AD7893 product line delivers compact, single-supply 12-bit serial ADCs with integrated track/hold for industrial and instrumentation applications demanding precision, speed, and board-space efficiency in harsh environments.

FAQ

What is the maximum recommended serial clock frequency for reliable operation of the AD7893BR-10?

The AD7893BR-10 supports a maximum SCLK frequency of 8.33 MHz, as specified in the timing characteristics table. At this rate, the serial read completes in 1.92 µs (16 cycles). Exceeding this frequency risks setup/hold violations on SDATA, causing invalid data capture. For robust operation in noisy industrial environments, Analog Devices recommends limiting SCLK to 5–7 MHz with proper PCB layout and decoupling.

Does the AD7893BR-10 require an external reference, and what are the key specifications for that reference?

Yes, the AD7893BR-10 requires an external +2.5 V reference applied to the REF IN pin. The reference must be stable within ±5% (2.375 V to 2.625 V), deliver ≤1 µA load current, and exhibit low noise (<10 µV p-p) to maintain 70 dB SNR. Precision references like the AD780 or ADR421 are recommended; reference drift directly causes proportional full-scale error in the AD7893BR-10 output.

How does the AD7893BR-10 handle timing synchronization without a dedicated BUSY or EOC pin?

The AD7893BR-10 uses the CONVST signal for timing coordination: conversion starts on its rising edge and completes exactly 6 µs later. Engineers synchronize reads either by inserting a 6 µs software delay after CONVST, or by using CONVST's falling edge as an interrupt to trigger the serial read - ensuring data is accessed only after conversion finishes and before the next cycle's 600 ns acquisition window.

What is the significance of twos-complement output coding in the AD7893BR-10, and how does it affect data interpretation?

Twos-complement coding allows the AD7893BR-10 to natively represent bipolar ±10 V inputs as signed 12-bit values (0x000 to 0xFFF maps to –2048 to +2047). This eliminates software sign-extension or offset subtraction in firmware, simplifying real-time control loops. For example, 0x800 = 0 V, 0xFFF = +10 V, and 0x000 = –10 V - directly matching the physical input range without post-processing.

Can the AD7893BR-10 operate with input signals exceeding ±10 V, and what are the absolute maximum ratings?

No - the AD7893BR-10's absolute maximum analog input rating is ±17 V, but operation beyond ±10 V violates the specified transfer function and risks code ambiguity or damage. The device is characterized only for ±10 V full-scale range; inputs above this level saturate the internal scaling network and may cause irreversible latch-up if sustained. Always use external clamping or attenuation for overvoltage protection.