Analog Devices Inc. AD7680BRMZ

Overview

AD7680BRMZ from Analog Devices is a 16-bit, unipolar, successive approximation ADC in a 6-lead SOT-23 package, operating from a single 2.5 V to 5.5 V supply with 100 kSPS throughput and 3 mW typical power at 2.5 V. It features internal VDD-referenced conversion, no pipeline delay, and SPI/QSPI/μWire/DSP-compatible serial interface for battery-powered data acquisition.

For engineers reviewing the AD7680BRMZ datasheet, AD7680BRMZ pinout, AD7680BRMZ application, or AD7680BRMZ equivalent, key selection considerations include its 6-lead SOT-23 footprint, 0 V to VDD analog input range, 8 μs max conversion time, 86 dB SNR at 10 kHz, and standby current of 0.5 μA - critical for portable medical instruments and remote sensor nodes.

Technical Context

The AD7680BRMZ implements a capacitive DAC-based successive approximation architecture with track-and-hold acquisition time ≤400 ns for sine-wave inputs ≤10 kHz and ≤1.5 μs for full-scale steps. Its conversion is initiated on the falling edge of CS and synchronized entirely to the external SCLK, eliminating pipeline latency.

Reference is derived directly from VDD, enabling a full-scale analog input range of 0 V to VDD without external reference components. Digital I/O supports mixed-voltage operation: logic inputs tolerate up to 7 V independent of VDD, while SDATA output levels swing from 0.4 V to VDD − 0.2 V under 200 μA load.

Key Specifications

Pinout & Package

AD7680BRMZ is housed in a RoHS-compliant 6-lead SOT-23 package (1.6 mm × 2.8 mm × 1.3 mm) with exposed pad option not specified. Pin functions are validated per Analog Devices Rev. A datasheet Figure 3 and Table 6.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with AD7680BRMZ, AD7683BRMZ trades higher speed for increased power and tighter timing constraints, while ADS8860IDRCT reduces active power but adds external reference complexity and larger footprint - making AD7680BRMZ optimal for space- and supply-constrained 100 kSPS applications needing integrated reference and minimal BOM.

Availability

AD7680BRMZ is available at Aetrix Electronics and suitable for battery-powered medical instruments, remote industrial data loggers, and portable optical sensor interfaces requiring stable component supply across long production lifecycles.

Supply support for AD7680BRMZ 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 semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD7680BRMZ belongs to the PulSAR® family of low-power, high-speed SAR ADCs designed specifically for space-constrained, battery-operated instrumentation where integration, accuracy, and energy efficiency are co-optimized.

FAQ

What is the maximum analog input frequency supported by the AD7680BRMZ?

The AD7680BRMZ supports a full-power bandwidth of 7 MHz at VDD = 4.096 V (−3 dB point), enabling accurate digitization of signals up to 5 MHz before significant amplitude roll-off occurs. For high-fidelity 10 kHz sine-wave inputs, it achieves 86 dB SNR and 97 dB THD, confirming suitability for audio-band and sensor signal conditioning applications.

Does the AD7680BRMZ require an external voltage reference?

No, the AD7680BRMZ does not require an external voltage reference. Its reference is derived internally from the VDD supply, establishing a 0 V to VDD unipolar input range. This eliminates external reference components, reduces BOM count, and simplifies layout - though VDD must be well-decoupled (0.1 μF ceramic + 10 μF tantalum) to maintain DC accuracy and dynamic performance.

How is the conversion triggered and timed in the AD7680BRMZ?

Conversion in the AD7680BRMZ is triggered on the falling edge of the CS pin, which simultaneously initiates track-and-hold acquisition and starts the SAR conversion process. The entire conversion completes within 8 μs (20 SCLK cycles at 2.5 MHz), with no pipeline delay. Data is clocked out MSB-first on SDATA synchronized to SCLK falling edges, supporting deterministic timing in real-time control systems.

What are the power consumption characteristics of the AD7680BRMZ at different supply voltages?

At 100 kSPS, AD7680BRMZ consumes 3 mW typical with 2.5 V supply, 3.9 mW at 3 V, and 16.7 mW at 5 V. In full power-down mode, it draws only 0.5 μA maximum regardless of VDD. These values reflect actual measured IDD: 1.75 mA typ at 4.096 V, 2.6 mA max at 100 kSPS; and 5.2 mA max at 5.5 V - enabling precise power budgeting for energy harvesting and coin-cell applications.

Can the AD7680BRMZ interface directly with 5 V logic microcontrollers?

Yes, the AD7680BRMZ digital inputs (CS, SCLK) tolerate up to 7 V, allowing direct connection to 5 V logic microcontrollers even when VDD = 2.5 V or 3.3 V. However, the SDATA output swings from 0.4 V to VDD − 0.2 V, so level-shifting may be needed for reliable 5 V MCU input recognition unless the MCU accepts 3.3 V–compatible logic thresholds.