Analog Devices Inc. AD7858LANZ

Overview

AD7858LANZ from Analog Devices is a 12-bit, 100 kSPS successive approximation register (SAR) analog-to-digital converter optimized for low-power operation in battery-powered systems. It features eight single-ended or four pseudo-differential analog inputs, on-chip 2.5 V reference, system/self-calibration, and SPI/QSPI/8051-compatible serial interface. Designed for medical instruments and portable instrumentation, it operates from a single 3 V to 5.5 V supply with 6.85 mW typical power dissipation at 3.6 V.

For engineers reviewing the AD7858LANZ datasheet, AD7858LANZ pinout, AD7858LANZ application, or AD7858LANZ equivalent, this page delivers verified technical context, calibrated performance data, package-specific terminal mapping, real-world use cases, and validated alternative options - all grounded in the official AD7858/AD7858L Rev. B datasheet and Analog Devices' ordering guide.

Technical Context

The AD7858LANZ implements a charge redistribution DAC-based SAR architecture with integrated track-and-hold, supporting both software- and hardware-triggered conversions via CONVST or control register write. Its calibration engine supports full self-calibration, system offset calibration, and internal DAC plus system full-scale calibration - all initiated via the CAL pin or control register.

It uses a flexible 16-bit serial interface with frame-sync (SYNC), serial clock (SCLK), bidirectional DIN/DOUT, and configurable read/write addressing via RDSLT bits. Power management includes three modes: normal (6.85 mW @ 3.6 V), partial power-down (200 µA), and full power-down (5 µA), controlled by PMGT1/PMGT0 bits and SLEEP pin.

Key Specifications

Pinout & Package

AD7858LANZ is supplied in a 24-lead plastic DIP (N-24) package with 0.3-inch width and through-hole mounting. Pin numbering follows standard dual-in-line layout with pin 1 at top-left corner (CONVST).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7858LANZ, AD7476AARMZ offers higher speed at lower power but demands external reference design and forfeits system-level calibration; ADS7822U provides compact packaging and matching power efficiency but omits pseudo-differential inputs and system calibration capability - making AD7858LANZ uniquely suited for precision, multi-channel, field-deployable measurement systems.

Availability

AD7858LANZ is available at Aetrix Electronics and suitable for portable medical instrumentation, handheld data acquisition, industrial pen computers, and high-speed modem analog front-ends requiring stable component supply and long-term lifecycle continuity.

Supply support for AD7858LANZ 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 AD7858/AD7858L product line was designed specifically for low-power, high-accuracy data acquisition in battery-operated and portable instrumentation - emphasizing integrated calibration, flexible power management, and robust serial interfacing.

FAQ

What is the maximum sample rate of the AD7858LANZ?

The AD7858LANZ has a maximum throughput rate of 100 kSPS, as confirmed in the "Features" and "GENERAL DESCRIPTION" sections of the AD7858/AD7858L Rev. B datasheet. This is the fixed specification for the 'L' (low-power) variant, distinguishing it from the 200 kSPS AD7858. The conversion time is 10 µs maximum under L-version conditions (1 MHz CLKIN, –40°C to +85°C), directly enabling this sustained sampling rate.

Does the AD7858LANZ include an internal voltage reference?

Yes, the AD7858LANZ integrates an internal 2.5 V reference with ±20 ppm/°C temperature coefficient, accessible at the REFIN/REFOUT pin. As stated in the "REFERENCE INPUT/OUTPUT" section, this reference is functional from 1.2 V to VDD and may be overdriven by an external source. The device also requires external 0.1 µF (CREF1) and 0.01 µF (CREF2) capacitors to AGND for stable operation - confirming its self-contained reference architecture.

How many analog input channels does the AD7858LANZ support?

The AD7858LANZ supports eight analog input channels (AIN1–AIN8), configurable as either eight single-ended inputs referenced to AGND or four pseudo-differential pairs. This is explicitly defined in the "FEATURES" list ("Eight Single-Ended or Four Pseudo-Differential Inputs") and verified in the "PIN FUNCTION DESCRIPTIONS" table (Pins 9–16). Channel selection is controlled via the SGL/DIFF and CH2–CH0 bits in the control register.

What power supply voltage range is supported by the AD7858LANZ?

The AD7858LANZ operates from a single supply voltage ranging from +3.0 V to +5.5 V on both AVDD and DVDD rails, as specified in the "ABSOLUTE MAXIMUM RATINGS" and "SPECIFICATIONS" tables. The "FEATURES" section confirms it is "Specified for VDD of 3 V to 5.5 V", and power dissipation data (e.g., 6.85 mW at 3.6 V) further validates operation across this range - with separate IDD values provided for 3.0–3.6 V and 4.5–5.5 V conditions.

Is automatic calibration on power-up supported by the AD7858LANZ?

Yes, the AD7858LANZ supports automatic self-calibration on power-up via the CAL pin. As described in the "PIN FUNCTION DESCRIPTIONS", connecting a 10 nF capacitor from CAL to DGND triggers autocalibration at startup. This capability is reinforced in the "PRODUCT HIGHLIGHTS" (item #2) and "SYSTEM CALIBRATION" section, which details offset and gain calibration spans - confirming that the AD7858LANZ implements this feature without requiring host processor intervention.