Texas Instruments ADS7822UB/2K5G4

Overview

ADS7822UB/2K5G4 from Texas Instruments is a 12-bit, 200kHz pseudo-differential SAR analog-to-digital converter in SO-8 package, operating from 2.7V to 5.25V supply with ±1 LSB integral linearity error and 3μA max power-down current. It features a synchronous 3-wire serial interface (CS/SHDN, DCLOCK, DOUT), 1.5-cycle acquisition time, and supports reference voltages from 50mV to VCC - ideal for battery-powered remote data acquisition systems.

For engineers reviewing the ADS7822UB/2K5G4 datasheet, ADS7822UB/2K5G4 pinout, ADS7822UB/2K5G4 application, or ADS7822UB/2K5G4 equivalent, key selection considerations include its microPower operation at 200kHz (320–550μA quiescent current), pseudo-differential input architecture, SO-8 thermal and layout compatibility, and guaranteed performance over –40°C to +85°C.

Technical Context

The ADS7822UB/2K5G4 implements a capacitive redistribution successive approximation register (SAR) architecture fabricated in 0.6μm CMOS, enabling true sample-and-hold functionality without external components. Its conversion cycle requires exactly 12 clock cycles after a 1.5-cycle acquisition window, with data output beginning on the second falling edge of DCLOCK.

It uses a synchronous 3-wire serial interface where CS/SHDN controls both chip select and shutdown mode: low enables conversion and serial output, high forces full power-down (digital and analog sections disabled). The pseudo-differential input (+In/–In) captures voltage difference directly onto the internal capacitor array at hold initiation - no resampling of –In occurs during conversion.

Key Specifications

Pinout & Package

ADS7822UB/2K5G4 is housed in an SO-8 (D package) surface-mount package measuring 4.90mm × 3.91mm × 1.75mm, with standard 1.27mm pitch and gull-wing leads suitable for reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U/2K5 and ADS7822UC/2K5, the ADS7822UB/2K5G4 provides the optimal balance of enhanced linearity (±1 LSB), production-tested reliability, and SO-8 compatibility - making it the preferred choice for mid-tier industrial and portable instrumentation where performance and cost must coexist.

Availability

ADS7822UB/2K5G4 is available at Aetrix Electronics and suitable for battery-operated systems, remote data acquisition, and isolated industrial monitoring requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for ADS7822UB/2K5G4 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision data converters and low-power design.

The ADS7822UB/2K5G4 belongs to TI's legacy precision SAR ADC product line, engineered specifically for ultra-low-power, space-constrained applications where microPower consumption and small SO-8 packaging are essential design requirements.

FAQ

What is the maximum sampling rate supported by the ADS7822UB/2K5G4?

The ADS7822UB/2K5G4 supports a maximum throughput rate of 200kHz when operated at VCC = 4.75V to 5.25V and fCLK = 3.2MHz. This corresponds to a minimum conversion time of 12 clock cycles plus 1.5-cycle acquisition window. At lower supply voltages (2.7V–3.6V), the maximum sample rate is reduced to 75kHz due to internal timing constraints.

Does the ADS7822UB/2K5G4 require an external reference voltage?

Yes, the ADS7822UB/2K5G4 requires an external reference voltage applied to the VREF pin. It accepts any stable reference from 50mV to VCC, and the full-scale input range is defined as +In – (–In) = VREF. No internal reference is provided - users must supply a low-noise, well-regulated reference matching their accuracy and power requirements.

How does the pseudo-differential input of the ADS7822UB/2K5G4 differ from a true differential input?

The ADS7822UB/2K5G4's pseudo-differential input samples the voltage difference between +In and –In at the start of conversion and holds it on the internal capacitor array. Unlike true differential ADCs, the –In pin has a restricted voltage range (–0.2V to +1.0V) and is not actively driven or resampled - it serves primarily as a remote ground reference rather than a fully symmetrical signal input.

Can the ADS7822UB/2K5G4 operate from a 3.3V supply?

Yes, the ADS7822UB/2K5G4 is fully specified for operation from 2.7V to 5.25V. At 3.3V supply, it achieves 75kHz maximum throughput with typical quiescent current of 200–325μA. The reference voltage must remain within 50mV to 3.3V, and logic levels remain compatible with 3.3V microcontrollers - DOUT swings 0V to 3.3V, and digital inputs tolerate up to 6V.

What is the purpose of the CS/SHDN pin on the ADS7822UB/2K5G4?

The CS/SHDN pin on the ADS7822UB/2K5G4 serves dual functions: when pulled low, it enables conversion and activates serial data output on DOUT; when driven high, it places the device into full power-down mode, reducing supply current to ≤3μA. This pin is essential for burst-mode operation, power cycling, and minimizing system-level standby power.