AD7858LARS

Overview

The AD7858LARS is an 8-channel, 12-bit successive approximation analog-to-digital converter (ADC) housed in a 24-lead SSOP package. It operates from a single 3 V to 5.5 V supply and delivers a throughput rate of 100 kSPS. The device features a flexible serial interface compatible with SPI, QSPI, and 8051 microprocessors. Key electrical specifications include a maximum conversion time of 10 µs at 1.8 MHz clock input, a typical power dissipation of 6.85 mW at 3 V, and integral nonlinearity of ±1 LSB. The ADC supports eight single-ended or four pseudo-differential inputs with an input range of 0 V to VREF.

Feature Summary

• Low-power optimized architecture designed for battery-operated applications
• Integrated system and self-calibration capabilities with automatic power-up calibration
• Flexible serial communication interface supporting multiple standard protocols
• Automatic power-down mode activated immediately after conversion completion

Applications

• Battery-powered personal digital assistants and mobile communications devices
• Medical instrumentation requiring low power consumption
• Pen computers and portable data acquisition systems
• Industrial instrumentation and control systems

Procurement Notes

Verify the specific suffix 'RS' confirms the 24-lead Shrink Small Outline Package (SSOP) form factor. Confirm the 'L' designation indicates the low-power variant with 100 kSPS throughput rather than the standard 200 kSPS version. Ensure environmental compliance documentation matches RoHS requirements for the intended manufacturing region.

Selection Notes

Select this component when a balance between moderate speed and minimal power consumption is required. The AD7858L offers lower power dissipation compared to the standard AD7858 but operates at half the sampling rate. Verify that the 100 kSPS throughput meets the system bandwidth requirements before choosing this model over higher-speed alternatives.

Part Context

This part belongs to the AD7858 family of high-speed, low-power 12-bit ADCs manufactured by Analog Devices Inc. The family includes variants optimized for speed (AD7858) and low power (AD7858L). The AD7858LARS specifically denotes the low-power version packaged in a 24-lead SSOP, distinguishing it from DIP and SOIC package options available within the same product line.

Replacement Considerations

The AD7858LARZ serves as a direct pin-compatible replacement offering identical electrical characteristics and functionality. Both parts share the same 100 kSPS throughput and low-power specifications. Verify package compatibility and lead-free status if transitioning between REEL and tube packaging formats.