Analog Devices Inc. AD7912ARMZ

Overview

AD7912ARMZ from Analog Devices is a 10-bit, dual-channel, successive-approximation analog-to-digital converter (ADC) operating from a single 2.35 V to 5.25 V supply, delivering up to 1 MSPS throughput with 61 dB SINAD at 100 kHz input and ±0.5 LSB integral nonlinearity. It features a track-and-hold amplifier supporting >6 MHz input bandwidth and is optimized for battery-powered data acquisition in portable medical instruments and PDA systems.

For engineers reviewing the AD7912ARMZ datasheet, AD7912ARMZ pinout, AD7912ARMZ application, or AD7912ARMZ equivalent, this page delivers verified specifications, validated daisy-chain interface behavior, confirmed TSOT-8 package mapping, and real-world channel-isolation (90 dB typ) and power-down (1 µA max) performance metrics essential for low-power embedded signal chain design.

Technical Context

The AD7912ARMZ implements a true successive-approximation register (SAR) architecture with no pipeline delay, enabling deterministic conversion timing controlled solely by CS and SCLK edges. Sampling is triggered on the falling edge of CS, and conversion completes in exactly 14 SCLK cycles (max 777 ns at 18 MHz), with acquisition time ≤290 ns.

It uses an internal VDD-referenced ADC core, eliminating external reference components, and supports SPI/QSPI/MICROWIRE/DSP-compatible serial interfacing. Channel selection is performed via DIN during CS assertion, and output data includes channel ID and mode bits - critical for multi-channel synchronization in daisy-chain configurations.

Key Specifications

Pinout & Package

AD7912ARMZ is packaged in an 8-lead TSOT (Thin Small Outline Transistor) with 0.5 mm pitch, optimized for space-constrained PCB layouts and compatible with standard reflow processes. Thermal impedance θ_JA = 207°C/W enables stable operation at ambient temperatures up to +85°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel SAR ADC applications.

Compared with AD7922ARMZ and ADS7822U, the AD7912ARMZ uniquely balances 1 MSPS speed, 10-bit precision, 1 µA standby, and TSOT-8 footprint - making it the most efficient choice for battery-powered, size-constrained dual-channel acquisition where 10-bit resolution meets system accuracy requirements.

Availability

AD7912ARMZ is available at Aetrix Electronics and suitable for portable medical instrumentation, PDA data acquisition, optical sensor interface, and industrial control loop monitoring requiring stable component supply and guaranteed long-term sourcing.

Supply support for AD7912ARMZ 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, headquartered in Norwood, MA, with decades of expertise in precision data conversion and signal conditioning.

The AD7912ARMZ belongs to Analog Devices' low-power, high-speed SAR ADC product line, designed specifically for space- and energy-constrained embedded systems requiring accurate, deterministic, multi-channel digitization without external references or complex support circuitry.

FAQ

What is the maximum sampling rate supported by the AD7912ARMZ?

The AD7912ARMZ supports a maximum throughput rate of 1 MSPS under specified conditions (VDD = 2.35 V to 5.25 V, fSCLK = 18 MHz). This is achieved with a fixed 14-SCLK conversion cycle, resulting in a minimum conversion time of 777 ns. At lower clock frequencies, throughput scales linearly - e.g., at 10 MHz SCLK, maximum rate is ~714 kSPS. The AD7912ARMZ maintains full DC and AC specifications across its entire rated speed range.

Does the AD7912ARMZ require an external voltage reference?

No, the AD7912ARMZ uses an internal reference derived from the VDD supply, enabling operation with a single 2.35 V to 5.25 V rail and eliminating the need for external reference components. This simplifies layout, reduces BOM cost, and avoids reference-related drift - though system-level accuracy remains dependent on VDD stability and noise. The AD7912ARMZ specification assumes VDD as reference; no external REF pin exists.

How does daisy-chain mode work on the AD7912ARMZ?

In daisy-chain mode, multiple AD7912ARMZ devices share a single CS and SCLK line, with DOUT of one device connected to DIN of the next. A single CS pulse initiates simultaneous sampling across all devices, and serial readout occurs sequentially: the first device outputs its 12-bit frame, followed immediately by the next device's frame on the same DOUT line. This mode reduces microcontroller pin count and synchronizes conversions without additional timing logic - fully supported in the AD7912ARMZ hardware.

What is the channel-to-channel isolation performance of the AD7912ARMZ?

The AD7912ARMZ provides 90 dB typical channel-to-channel isolation, measured by applying a full-scale sine wave to the unselected input while digitizing the selected channel. This high isolation ensures minimal crosstalk between VIN0 and VIN1 - critical when measuring independent, high-gain analog sources (e.g., photodiode + temperature sensor) on shared PCB traces or ground planes. The value is consistent across temperature and supply voltage ranges per Analog Devices characterization.

Can the AD7912ARMZ operate from a 2.5 V supply?

Yes, the AD7912ARMZ is fully specified for operation from 2.35 V to 5.25 V, including 2.5 V. At 2.5 V, it delivers 1 MSPS throughput, 61 dB SINAD (min), ±0.5 LSB INL, and 6 mW max power dissipation. Logic thresholds adapt automatically: VINH = 0.7 × VDD (1.75 V min) and VINL = 0.3 V max. The device remains functional down to 2.0 V (with reduced VIH/VIL margins), but full AC/DC specs apply only within the 2.35–5.25 V range.