Analog Devices Inc. AD7853ARS

Overview

AD7853ARS from Analog Devices is a 12-bit, 200 kSPS pseudo-differential successive-approximation ADC operating from a single 3 V to 5.5 V supply. It integrates on-chip 2.5 V reference, self- and system-calibration, flexible SPI/QSPI/8051-compatible serial interface, and automatic power-down after conversion. Designed for battery-powered instrumentation and portable medical devices requiring high accuracy at low power.

For engineers reviewing the AD7853ARS datasheet, AD7853ARS pinout, AD7853ARS application, or AD7853ARS equivalent, key selection criteria include its 200 kSPS throughput, ±1 LSB INL (B-grade), 71 dB SNR at 10 kHz, 4.6 µs conversion time, and SSOP-24 package compatibility with space-constrained embedded data acquisition systems.

Technical Context

The AD7853ARS implements a charge-redistribution SAR architecture with integrated track-and-hold acquiring in 500 ns. Its analog front end supports unipolar (0 to VREF) and bipolar (±VREF/2) input ranges via AMODE pin control, with AIN(+) and AIN(–) accepting signals up to AVDD while maintaining pseudo-differential sampling integrity.

Calibration logic includes automatic power-up self-calibration triggered by CAL pin, offset/gain calibration spans of ±0.05 × VREF and ±0.025 × VREF respectively, and configurable power management (PMGT bits) enabling full or partial power-down modes with sub-1 µA sleep current when CLKIN is off.

Key Specifications

Pinout & Package

AD7853ARS is housed in a 24-lead Small Shrink Outline Package (SSOP), 0.150-inch body width, gull-wing lead form, RoHS-compliant. Pin pitch is 0.025 inch (0.635 mm); package dimensions are 7.6 mm × 5.0 mm × 1.8 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7853BR and ADS7822U, the AD7853ARS uniquely combines SSOP-24 miniaturization, ±1 LSB INL performance, and full self/system calibration in a single-chip solution-making it optimal for space-constrained, high-accuracy portable instrumentation where long-term drift compensation is critical.

Availability

AD7853ARS is available at Aetrix Electronics and suitable for portable medical instrumentation, battery-powered data loggers, industrial process monitoring, and high-speed modem analog front ends requiring stable component supply and long-term production continuity.

Supply support for AD7853ARS 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 AD7853ARS belongs to Analog Devices' precision SAR ADC product line, engineered for portable, low-power, high-accuracy data acquisition in battery-operated and space-constrained systems where calibration stability and interface flexibility are essential.

FAQ

What is the maximum sampling rate supported by the AD7853ARS?

The AD7853ARS supports a maximum throughput rate of 200 kSPS under standard operating conditions with a 4 MHz master clock. This corresponds to a minimum conversion time of 4.6 µs. The actual achievable rate depends on interface mode selection, SCLK timing, and BUSY signal handshaking; Interface Modes 2 and 3 allow back-to-back conversions during read/write cycles to sustain full 200 kSPS throughput. The AD7853ARS maintains this rate across its full –40°C to +85°C industrial temperature range when powered from 3.0 V to 5.5 V.

Does the AD7853ARS require external calibration components?

No, the AD7853ARS does not require external calibration components for basic operation. It features on-chip self-calibration triggered automatically on power-up when a 10 nF capacitor is connected from the CAL pin to DGND. System calibration is also supported using the same CAL pin and internal registers, allowing correction of external signal chain errors without additional hardware. External reference decoupling capacitors (CREF1 = 0.1 µF, CREF2 = 0.01 µF) are required but are standard passive components-not calibration elements.

Can the AD7853ARS operate with a 3.3 V supply and still achieve full 12-bit performance?

Yes, the AD7853ARS is fully specified for operation from 3.0 V to 5.5 V, including 3.3 V nominal supplies. At 3.3 V, it maintains 12-bit resolution, ±1 LSB integral nonlinearity (B grade), 71 dB SNR at 10 kHz, and 200 kSPS throughput-provided AVDD and DVDD are both supplied at 3.3 V and all logic thresholds (VINH/VINL) remain within specification. Power dissipation drops to approximately 6.85 mW, and sleep current remains below 1 µA with external clock disabled-making it ideal for 3.3 V embedded systems.

What serial interface protocols does the AD7853ARS support out of the box?

AD7853ARS supports five configurable serial interface modes selectable via SM1 and SM2 pins, enabling native compatibility with SPI, QSPI, and 8051 microcontroller buses without protocol translation. Mode selection determines whether SCLK is input or output, SYNC acts as chip select or frame sync, and whether data transfer is continuous or noncontinuous. POLARITY pin further configures SCLK idle state (high/low). No firmware driver modification is needed-the AD7853ARS adapts its timing and signaling to match the host controller's native protocol behavior.

Is the AD7853ARS pin-compatible with other members of the AD7853 family?

Yes, the AD7853ARS is pin-compatible with all AD7853 and AD7853L variants in the same SSOP-24 package, including AD7853LARS. Differences between AD7853 and AD7853L relate to speed (200 kSPS vs 100 kSPS) and power (12 mW vs 4.5 mW at 3 V), not pin function or layout. All share identical pin assignments, electrical characteristics, register map, and interface behavior-allowing drop-in substitution where throughput and power targets align. The "L" suffix denotes lower-speed, lower-power optimization; "ARS" denotes SSOP-24 packaging.