Analog Devices Inc. AD7920AKSZ-REEL7

Overview

AD7920AKSZ-REEL7 from Analog Devices is a 12-bit, 250 kSPS successive approximation ADC in a 6-lead SC70 package, operating from a single 2.35 V to 5.25 V supply. It features 71 dB SNR at 100 kHz input, 0–VDD analog input range, and SPI-/QSPI-/MICROWIRE-compatible serial interface. It serves as the primary analog-to-digital conversion stage in portable medical sensors and battery-powered data loggers.

For engineers reviewing the AD7920AKSZ-REEL7 datasheet, AD7920AKSZ-REEL7 pinout, AD7920AKSZ-REEL7 application, or AD7920AKSZ-REEL7 equivalent, key selection considerations include its 12-bit resolution with ±1.5 LSB INL, 250 ns track-and-hold acquisition time, 1 μA max standby current, and internal VDD-referenced architecture eliminating external reference components.

Technical Context

The AD7920AKSZ-REEL7 implements a charge redistribution SAR architecture with integrated track-and-hold, enabling precise sampling of signals up to 13.5 MHz full-power bandwidth. Its conversion is initiated by the falling edge of CS and clocked entirely by SCLK-requiring 16 cycles at 5 MHz for a 3.2 μs max conversion time.

All timing, power management, and serial output formatting (four leading zeros + 12-bit MSB-first data) are tightly coupled to the SCLK signal. The device derives its reference directly from VDD, resulting in a 0 V to VDD input range and eliminating need for external voltage references or level-shifting circuitry.

Key Specifications

Pinout & Package

AD7920AKSZ-REEL7 is housed in a 6-lead SC70 package (2.0 mm × 1.25 mm × 0.9 mm), optimized for space-constrained portable electronics. Pin assignments are validated per Analog Devices Rev. C datasheet Figure 5 and Table 5.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7920AKSZ-REEL7, AD7923BRMZ-REEL adds channel count and speed at the cost of board area and external reference dependency, while ADS7822U trades SC70 miniaturization and VDD referencing for SOIC manufacturability and TI toolchain alignment.

Availability

AD7920AKSZ-REEL7 is available at Aetrix Electronics and suitable for battery-powered systems, portable medical instruments, and wireless sensor networks requiring stable component supply across long production lifecycles.

Supply support for AD7920AKSZ-REEL7 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 AD79xx family was designed specifically for space- and power-constrained data acquisition in portable instrumentation, offering integrated reference, ultra-small packages, and guaranteed performance across industrial temperature ranges.

FAQ

What is the maximum sampling rate supported by the AD7920AKSZ-REEL7?

The AD7920AKSZ-REEL7 supports a maximum throughput rate of 250 kSPS, achieved with a 5 MHz SCLK and 16-cycle conversion sequence. This corresponds to a minimum conversion time of 3.2 μs. At lower SCLK frequencies, throughput scales linearly-for example, 3.4 MHz yields ~150 kSPS-enabling flexible power-throughput trade-offs in battery-operated systems.

Does the AD7920AKSZ-REEL7 require an external voltage reference?

No, the AD7920AKSZ-REEL7 does not require an external voltage reference. Its reference is derived internally from the VDD supply, establishing a 0 V to VDD analog input range. This eliminates external reference components, reduces BOM cost, and simplifies layout-particularly valuable in SC70-based portable designs where board area is at a premium.

What is the analog input voltage range for the AD7920AKSZ-REEL7?

The AD7920AKSZ-REEL7 has an analog input voltage range of 0 V to VDD. With VDD configurable from 2.35 V to 5.25 V, this means the input range dynamically adjusts to the supply rail-e.g., 0–3.3 V at 3.3 V operation or 0–5.0 V at 5.0 V operation. Input overvoltage protection extends to VDD + 0.3 V per Absolute Maximum Ratings.

How does the AD7920AKSZ-REEL7 enter and exit power-down mode?

The AD7920AKSZ-REEL7 enters full power-down mode when CS remains high for more than 100 ns after the completion of a conversion cycle. It exits power-down and becomes ready for the next conversion within 1 μs of the subsequent CS falling edge. During power-down, supply current drops to ≤1 μA, making it ideal for duty-cycled sensor acquisition.

What serial interface protocols is the AD7920AKSZ-REEL7 compatible with?

The AD7920AKSZ-REEL7 features a standard SPI-compatible serial interface that operates in Mode 0 (CPOL = 0, CPHA = 0), supporting direct connection to SPI, QSPI, MICROWIRE, and common DSP host controllers. Data is clocked out MSB-first on the falling edge of SCLK, preceded by four leading zeros-ensuring interoperability without protocol translation hardware.