Analog Devices Inc. AD7829BRUZ-1

Overview

AD7829BRUZ-1 from Analog Devices is a high-speed, 8-channel, microprocessor-compatible 8-bit analog-to-digital converter with 2 MSPS throughput, 420 ns conversion time, on-chip 2.5 V reference, and flexible parallel interface - used in DSP front ends and mobile communication subsampling systems.

For engineers reviewing the AD7829BRUZ-1 datasheet, AD7829BRUZ-1 pinout, AD7829BRUZ-1 application, or AD7829BRUZ-1 equivalent, key selection considerations include single-supply 3 V/5 V operation, channel-select-on-read architecture, automatic power-down via CONVST, VMID-adjustable input span, and 10 MHz full-power bandwidth for subsampling.

Technical Context

The AD7829BRUZ-1 employs a half-flash ADC architecture with two-stage conversion: a 4-bit coarse flash followed by a 4-bit fine flash, achieving full 8-bit resolution in ≤420 ns. Its track-and-hold amplifier supports full-scale input signals up to 10 MHz (FPBW), enabling direct RF subsampling without external anti-alias filtering in select applications.

Channel selection is performed via address inputs A2–A0 sampled at RD falling edge, eliminating register writes. The CONVST pin serves dual function: initiating conversion on its falling edge and triggering automatic power-down when sampled low at EOC assertion - enabling precise per-conversion energy control.

Key Specifications

Pinout & Package

The AD7829BRUZ-1 is housed in a 28-lead TSSOP package (thin shrink small outline package), pin-compatible with the SOIC_W variant but with reduced footprint and thermal resistance (θJA = 128°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit, high-speed ADC applications.

Compared with AD7829BRUZ-1, AD7829BRUZ lacks industrial temperature qualification, while MAX1186EEE+ trades parallel simplicity for serial compactness and external reference dependency - making AD7829BRUZ-1 optimal for microprocessor-based systems needing robust, self-contained, high-throughput analog capture.

Availability

AD7829BRUZ-1 is available at Aetrix Electronics and suitable for data acquisition systems, disk drive servo control, and mobile communication subsampling applications requiring stable component supply across industrial temperature ranges and long-term production continuity.

Supply support for AD7829BRUZ-1 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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD7829 product line delivers high-speed, low-power, microprocessor-compatible ADCs optimized for real-time data acquisition, DSP interfacing, and subsampling applications in industrial and communications equipment.

FAQ

What is the maximum input frequency the AD7829BRUZ-1 can accurately digitize?

The AD7829BRUZ-1 has a full-power bandwidth (FPBW) of 10 MHz, meaning it maintains full-scale accuracy for sinusoidal inputs up to 10 MHz. This enables direct subsampling of IF signals in communications systems without external anti-alias filtering, provided Nyquist criteria are met for the chosen sampling rate. Performance is verified per Table 1 specifications at fIN = 10 MHz.

How does the AD7829BRUZ-1 handle different supply voltages (3 V vs. 5 V)?

The AD7829BRUZ-1 incorporates an internal VDD detector that automatically configures input span and reference scaling: at 5 V ±10%, input range is 0 V to 2.5 V p-p with 2.5 V on-chip reference; at 3 V ±10%, range is 0 V to 2 V p-p with scaled LSB size (0.8 × VREF/256). No external configuration is needed - behavior is fully transparent to the user.

Can the AD7829BRUZ-1 operate in stand-alone mode without a microprocessor?

Yes - the AD7829BRUZ-1 supports stand-alone operation using its EOC pulse to strobe external latches or trigger logic. With fixed channel selection (A2–A0 tied), CONVST driven by a free-running clock, and RD/CS asserted, the device continuously converts and outputs data on DB0–DB7. This mode is documented in the Parallel Interface section of the datasheet.

What is the role of the VMID pin on the AD7829BRUZ-1, and how is it used?

The VMID pin sets the center voltage of the AD7829BRUZ-1's analog input span. When left unconnected, it defaults to 1.25 V (5 V supply) or 1.0 V (3 V supply), yielding input ranges of 0 V–2.5 V or 0 V–2 V. Applying an external voltage shifts the span symmetrically - e.g., 2.0 V on VMID yields ±1.25 V range at 5 V supply - enabling bipolar signal capture and system offset cancellation.

Does the AD7829BRUZ-1 require external decoupling capacitors, and where should they be placed?

Yes - the AD7829BRUZ-1 requires local decoupling: a 0.1 μF ceramic capacitor between VDD and AGND/DGND (tied together at the package), and a 10 μF bulk capacitor on the VDD supply rail. VREF IN/OUT should be decoupled with 0.1 μF to AGND if using the internal reference. These values are specified in Figure 7 (Typical Connection Diagram) and minimize noise-induced INL/DNL degradation.