Analog Devices Inc. AD7829BRW-1

Overview

AD7829BRW-1 from Analog Devices is a high-speed, 8-channel, 8-bit analog-to-digital converter (ADC) with 2 MSPS throughput, 420 ns conversion time, on-chip 2.5 V reference, and flexible parallel interface. It operates from single 3 V ±10% or 5 V ±10% supply and supports data acquisition in DSP front ends and mobile communication subsampling applications.

For engineers reviewing the AD7829BRW-1 datasheet, AD7829BRW-1 pinout, AD7829BRW-1 application, or AD7829BRW-1 equivalent, key selection considerations include its half-flash architecture, automatic power-down via CONVST, VMID-adjustable input span, channel-to-channel isolation of −70 dB, and compatibility with 8051/PIC/ADSP microcontrollers.

Technical Context

The AD7829BRW-1 employs an 8-bit half-flash ADC architecture with two-stage conversion: a 4-bit coarse flash followed by a 4-bit fine flash, completing within 420 ns max. Its track-and-hold amplifier features 200 ns acquisition time and full-power bandwidth up to 10 MHz, enabling accurate subsampling of high-frequency signals.

Channel selection is performed externally via A0–A2 address inputs, independent of 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-eliminating need for separate control logic.

Key Specifications

Pinout & Package

The AD7829BRW-1 is housed in a 28-lead wide-body SOIC (SOIC_W) package, compatible with standard surface-mount assembly processes and offering thermal impedance of 75°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 AD7829BRW-1, the AD7829BRUZ offers identical performance in a smaller footprint but demands more careful thermal layout, while the MAX1186EEE+ trades conversion speed and integrated features for lower dynamic power and simpler supply chain integration.

Availability

AD7829BRW-1 is available at Aetrix Electronics and suitable for disk drive servo systems, mobile baseband receivers, DSP-based motor controllers, and industrial data acquisition modules requiring stable component supply across extended production lifecycles.

Supply support for AD7829BRW-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 family was designed specifically for high-throughput, low-latency data acquisition in real-time embedded systems-emphasizing fast conversion, flexible interfacing, and analog signal conditioning without external support components.

FAQ

What is the maximum input frequency the AD7829BRW-1 can accurately digitize?

The AD7829BRW-1 has a full-power bandwidth (FPBW) of 10 MHz for its track-and-hold amplifier, meaning it maintains full-scale accuracy for sinusoidal inputs up to 10 MHz. This is confirmed in the Product Highlights and Specifications sections of the datasheet, where SNR and distortion metrics are validated at f_IN = 10 MHz. The AD7829BRW-1 is explicitly recommended for subsampling applications leveraging this capability.

Does the AD7829BRW-1 require an external reference, or does it have an internal one?

The AD7829BRW-1 includes an on-chip 2.5 V reference with ±50 mV error and 50 ppm/°C temperature coefficient. The VREF IN/OUT pin provides access to this internal reference or accepts an external 2.5 V source. Using the internal reference eliminates the need for external components in cost-sensitive designs, while the external option improves long-term stability and temperature drift performance for precision applications involving the AD7829BRW-1.

How does the VMID pin affect the input voltage range of the AD7829BRW-1?

The VMID pin sets the center point of the AD7829BRW-1's analog input span: with VDD = 3 V, input range becomes VMID ±1.0 V; with VDD = 5 V, it becomes VMID ±1.25 V. When left unconnected, VMID defaults to 1.0 V (3 V) or 1.25 V (5 V), yielding 0–2 V or 0–2.5 V ranges respectively. This feature allows the AD7829BRW-1 to accommodate bipolar signals or compensate for system-level DC offsets without external amplifiers.

Can the AD7829BRW-1 operate in standalone mode without a microprocessor?

Yes-the AD7829BRW-1 supports standalone operation using its EOC (end-of-conversion) pulse to trigger external latches or interrupt logic. The parallel interface requires only address decoding (A0–A2) and basic control (CONVST, RD, CS); no internal registers or configuration writes are needed. This makes the AD7829BRW-1 suitable for gate-array or FPGA-based systems where minimal glue logic is desired.

What is the power consumption of the AD7829BRW-1 during normal operation and power-down?

In normal operation at 2 MSPS, the AD7829BRW-1 draws up to 12 mA (typically 8 mA) from VDD, resulting in ~36 mW max power dissipation at 3 V. In automatic power-down mode-activated when CONVST is sampled low at EOC-it consumes just 0.2 μA typical (5 μA max). This ultra-low standby current significantly reduces average power in burst-mode acquisition systems using the AD7829BRW-1.