Analog Devices Inc. AD7989-1BCPZ-RL7

Overview

AD7989-1BCPZ-RL7 from Analog Devices is an 18-bit, 100 kSPS successive approximation register (SAR) analog-to-digital converter with true differential input, ±V_REF range, zero-latency architecture, and 99 dB dynamic range at 5 V reference-designed for high-precision data acquisition in medical instruments and automated test equipment.

For engineers reviewing the AD7989-1BCPZ-RL7 datasheet, AD7989-1BCPZ-RL7 pinout, AD7989-1BCPZ-RL7 application, or AD7989-1BCPZ-RL7 equivalent, this page delivers verified specifications including INL (±2 LSB max), SNR (98 dB), THD (−119 dB), power dissipation (700 µW total at 100 kSPS), and LFCSP-10 package compatibility.

Technical Context

The AD7989-1BCPZ-RL7 implements a charge redistribution SAR architecture with on-chip track-and-hold, enabling true zero-latency conversion and no pipeline delay. Its differential input stage accepts ±V_REF signals with 67 dB common-mode rejection at 450 kHz and supports external reference voltages from 2.4 V to 5.1 V.

Digital interface operates via SPI-/QSPI-/MICROWIRE-/DSP-compatible 3- or 4-wire serial protocol with daisy-chain capability. It features dual-supply operation: 2.5 V V_DD core supply and independent 1.71 V–5.5 V V_IO for logic-level flexibility across 1.8 V, 2.5 V, 3 V, and 5 V host systems.

Key Specifications

Pinout & Package

AD7989-1BCPZ-RL7 is housed in a 3 mm × 3 mm, 10-lead LFCSP (CP-10-9) package with exposed pad. The package supports low thermal resistance (θ_JA = 48.7°C/W, θ_JC = 2.96°C/W) and is rated for −40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 18-bit SAR ADC applications.

Compared with AD7989-1BCPZ-RL7, AD7691BRMZ-RL7 trades 2.5× higher power for 2.5× throughput and simplified timing, while AD4021BRMZ demands redesign of analog front-end and power delivery to meet its 3.3 V V_DD requirement and driver dependency.

Availability

AD7989-1BCPZ-RL7 is available at Aetrix Electronics and suitable for medical instrumentation, automated test equipment, and industrial data acquisition systems requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for AD7989-1BCPZ-RL7 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 design centers worldwide.

The AD7989 family targets precision, low-power, high-speed data acquisition-optimized for applications demanding 18-bit resolution, zero latency, and flexible digital interfacing without sacrificing size or thermal performance.

FAQ

What is the maximum sampling rate of the AD7989-1BCPZ-RL7?

The AD7989-1BCPZ-RL7 has a fixed maximum throughput of 100 kSPS, confirmed in the Rev. C datasheet Table 2 and Timing Specifications section. This rate is guaranteed across the full operating temperature range (−40°C to +85°C) and is not user-configurable-unlike the pin-compatible AD7989-5 variant, which supports 500 kSPS. The AD7989-1BCPZ-RL7 achieves this with 700 µW total power dissipation at 100 kSPS.

Does the AD7989-1BCPZ-RL7 require an external reference voltage?

Yes, the AD7989-1BCPZ-RL7 requires an external reference voltage applied to the REF pin, with a specified range of 2.4 V to 5.1 V. The device does not include an internal reference. The datasheet mandates local decoupling using a 10 µF capacitor between REF and GND to maintain SNR and THD performance. Reference load current is 250 µA at 5 V, and PSRR is 90 dB, making it sensitive to reference noise.

What package type is used for the AD7989-1BCPZ-RL7?

The AD7989-1BCPZ-RL7 uses a 3 mm × 3 mm, 10-lead LFCSP package (Analog Devices part number suffix "BCPZ" denotes CP-10-9). This package features an exposed pad that may be connected to GND for improved thermal performance (θ_JC = 2.96°C/W), though electrical functionality is maintained without it. Pin configuration matches Figures 4 and Table 7 in the Rev. C datasheet.

Can the AD7989-1BCPZ-RL7 interface directly with a 1.8 V microcontroller?

Yes, the AD7989-1BCPZ-RL7 supports 1.8 V logic interfaces via its dedicated VIO supply pin (1.71 V to 5.5 V range). When VIO = 1.8 V, digital input thresholds adjust accordingly (e.g., VIH ≥ 0.9 × VIO = 1.62 V), and VOL/VOL specs remain valid. This eliminates level shifters in mixed-voltage systems-confirmed in Table 3 Digital Inputs/Outputs specifications and General Description section.

What is the analog input structure of the AD7989-1BCPZ-RL7?

The AD7989-1BCPZ-RL7 features a true differential analog input pair (IN+, IN−) with a voltage range of ±VREF and a common-mode window of VREF × 0.475 to VREF × 0.525. It does not support pseudo-differential or single-ended modes. Input leakage is 200 nA (typical), and CMRR is 67 dB at 450 kHz-enabling high-fidelity acquisition of small differential signals in electrically noisy environments without external amplification.