Analog Devices Inc. AD7683BCPZRL7

Overview

AD7683BCPZRL7 from Analog Devices is a 16-bit, pseudo-differential, successive-approximation ADC with 100 kSPS throughput, ±1 LSB typical INL, SPI/QSPI/MICROWIRE-compatible serial interface, and single-supply operation from 2.7 V to 5.5 V. It delivers 90 dB SNR at 1 kHz and supports battery-powered instrumentation requiring high resolution without missing codes.

For engineers reviewing the AD7683BCPZRL7 datasheet, AD7683BCPZRL7 pinout, AD7683BCPZRL7 application, or AD7683BCPZRL7 equivalent, key selection criteria include its 100 kSPS conversion rate, 1 nA standby current, 8-lead QFN (LFCSP) package, 0 V to VREF analog input range, and compatibility with low-noise driver amplifiers like ADA4841-1 for precision data acquisition.

Technical Context

The AD7683BCPZRL7 uses a charge redistribution SAR architecture with integrated track-and-hold, enabling zero-latency conversion and no pipeline delay. Its pseudo-differential input accepts +IN/–IN signals referenced to ground sense, supporting remote ground sensing and common-mode rejection.

It operates with an external reference voltage (0.5 V to VDD), features internal conversion clocking, and scales power linearly with throughput-consuming only 150 µW at 10 kSPS/2.7 V. The serial interface requires 22–24 DCLOCK cycles per 16-bit conversion and supports CS-controlled shutdown.

Key Specifications

Pinout & Package

The AD7683BCPZRL7 is housed in an 8-lead 3 mm × 3 mm QFN (LFCSP) package with exposed pad (EPAD), rated for −40°C to +85°C operation. The EPAD must be connected to GND for thermal performance but is not required for electrical functionality.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7683BCPZRL7, AD7685BRMZ offers higher throughput and tighter INL but increases power and timing constraints, while ADS8325IPW trades integration and low-power features for vendor-specific toolchain alignment.

Availability

AD7683BCPZRL7 is available at Aetrix Electronics and suitable for battery-powered equipment, medical instruments, industrial process sensors, and portable test equipment requiring stable component supply over extended production lifecycles.

Supply support for AD7683BCPZRL7 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 AD7683BCPZRL7 belongs to the PulSAR® family of precision SAR ADCs designed for low-power, high-resolution data acquisition in space-constrained, battery-sensitive applications from −40°C to +85°C.

FAQ

What is the maximum DCLOCK frequency supported by the AD7683BCPZRL7?

The AD7683BCPZRL7 supports a maximum DCLOCK frequency of 2.9 MHz, as specified in the Absolute Maximum Ratings and Timing Specifications tables. This allows full 16-bit conversion within the 10 µs complete cycle time. Exceeding this limit risks data corruption or incomplete conversions. The AD7683BCPZRL7 requires 22–24 clock edges per conversion, so system clocking must accommodate this constraint at 100 kSPS throughput.

Does the AD7683BCPZRL7 require an external reference voltage?

Yes, the AD7683BCPZRL7 requires an external reference voltage applied to the REF pin, which must be between 0.5 V and VDD. It does not include an internal reference. For optimal performance, Analog Devices recommends using a low-drift, low-noise reference such as the ADR435, decoupled with a 10 µF X5R ceramic capacitor directly between REF and GND. The AD7683BCPZRL7 draws up to 50 µA from REF at 100 kSPS, so the reference source must sustain this load without droop.

Can the AD7683BCPZRL7 operate from a 3.3 V supply?

Yes, the AD7683BCPZRL7 operates from 2.7 V to 5.5 V, fully supporting 3.3 V single-supply operation. At 3.3 V and 100 kSPS, typical operating current is ~650 µA, yielding ~2.15 mW power dissipation. All specifications-including INL, SNR, and timing-are guaranteed across this range. Digital logic levels scale with VDD, so 3.3 V microcontrollers interface directly without level shifters.

What is the purpose of the –IN pin on the AD7683BCPZRL7?

The –IN pin on the AD7683BCPZRL7 serves as the analog ground sense reference for the pseudo-differential input, enabling rejection of common-mode noise and elimination of ground potential differences between remote sensors and the ADC. It is not a true differential input but allows the +IN voltage to be measured relative to –IN, supporting 0 V to VREF input range. Connecting –IN to a remote sensor ground plane improves accuracy in noisy industrial environments where ground loops would otherwise degrade measurement fidelity.

Is the AD7683BCPZRL7 pin-compatible with the AD7685BRMZ?

No, the AD7683BCPZRL7 is not pin-compatible with the AD7685BRMZ. Although both are 8-lead QFN (LFCSP) SAR ADCs from Analog Devices and share identical pin numbering and functions (REF, +IN, –IN, GND, CS, DOUT, DCLOCK, VDD), the AD7685BRMZ requires a minimum DCLOCK frequency of 5 MHz and has different timing margins-particularly tSUCS (CS setup to DCLOCK rise) and tEN (DCLOCK fall to data valid). PCB layout reuse is possible, but firmware and timing validation must be re-performed for AD7685BRMZ integration.