Texas Instruments ADS7816E/2K5G4

Overview

ADS7816E/2K5G4 from Burr-Brown (now Texas Instruments) is a 12-bit, 200kHz SAR analog-to-digital converter with differential input, synchronous serial interface, and programmable reference range (100mV–5V). It delivers 1.9mW power at full rate, 3µA shutdown current, and ±2 LSB integral linearity - optimized for remote, isolated, or battery-powered data acquisition.

For engineers reviewing the ADS7816E/2K5G4 datasheet, ADS7816E/2K5G4 pinout, ADS7816E/2K5G4 application, or ADS7816E/2K5G4 equivalent, key selection considerations include its MSOP-8 package, micro-power operation at variable sample rates (12.5kHz–200kHz), differential input tolerance (±200mV on –In), reference-dependent LSB resolution (24µV–1.22mV), and CMOS-compatible serial timing with CS/SHDN-controlled power-down.

Technical Context

The ADS7816E/2K5G4 implements a capacitive redistribution SAR architecture fabricated in 0.6µm CMOS, enabling single-supply +5V operation with inherent sample-and-hold. Its conversion cycle requires exactly 12 clock cycles, with 1.5-cycle acquisition time, and supports external clock frequencies from 10kHz to 3.2MHz.

It uses a 3-wire synchronous serial interface (CS/SHDN, DCLOCK, DOUT) where data is output MSB-first on DOUT's falling edge; the first bit after CS assertion is a null bit, followed by 12 valid bits. Reference current scales with sample rate and code value - ranging from 2.4µA at 12.5kHz to 100µA at 200kHz for mid-scale codes.

Key Specifications

Pinout & Package

The ADS7816E/2K5G4 is housed in an 8-lead MSOP package (3.0mm × 3.0mm, 0.65mm pitch), optimized for space-constrained PCB layouts while maintaining thermal and electrical performance comparable to SOIC and PDIP variants.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7816U and ADS7822U, the ADS7816E/2K5G4 uniquely combines MSOP-8 miniaturization, external reference programmability down to 100mV, and lowest active power (1.9mW), making it optimal for space- and energy-constrained differential sensing.

Availability

ADS7816E/2K5G4 is available at Aetrix Electronics and suitable for portable instrumentation, isolated industrial I/O modules, medical wearables, and thermocouple-based process control systems requiring stable component supply across long production lifecycles.

Supply support for ADS7816E/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

Burr-Brown Corporation, acquired by Texas Instruments in 2000, specialized in precision analog ICs including data converters, op amps, and voltage references.

The ADS7816E/2K5G4 belongs to Burr-Brown's micro-power SAR ADC family designed specifically for battery-operated and remote data acquisition where low standby current, differential input integrity, and reference flexibility are critical.

FAQ

What is the minimum reference voltage supported by the ADS7816E/2K5G4?

The ADS7816E/2K5G4 supports a reference voltage as low as 100mV, enabling high-resolution digitization of low-level sensor outputs such as thermocouples. At this setting, LSB size is 24µV, and effective number of bits remains ≥10.5 per published ENOB curves - provided layout follows low-noise guidelines including local 0.1µF bypassing at VREF.

Does the ADS7816E/2K5G4 require an external clock source?

Yes, the ADS7816E/2K5G4 requires an external DCLOCK signal between 10kHz and 3.2MHz to control conversion timing and serial data output. The clock duty cycle is flexible as long as high/low times exceed 150ns. For lowest power, TI recommends running DCLOCK at 3.2MHz and using CS/SHDN to gate activity - allowing the ADS7816E/2K5G4 to spend maximum time in 3µA shutdown mode.

Can the ADS7816E/2K5G4 perform true differential measurements?

The ADS7816E/2K5G4 accepts differential input between +In and –In pins, but –In is restricted to ±200mV relative to GND. This limits common-mode rejection to small offsets - ideal for remote ground sensing, not full-rail differential signals. True differential operation requires the voltage difference (+In − –In) to stay within 0 to VREF, and –In must be tied to a stable local or remote ground point, not a swinging signal.

What is the purpose of the null bit in the ADS7816E/2K5G4 serial output?

The null bit is the first bit output on DOUT after CS falls; it has no data value and serves as a synchronization marker indicating that conversion has started and the next 12 bits are valid MSB-first data. This design ensures deterministic timing alignment between host controller and ADC - especially critical when interfacing with microcontrollers lacking dedicated SPI hardware or using bit-banged GPIO reads.

How does power consumption scale with sample rate in the ADS7816E/2K5G4?

ADS7816E/2K5G4 quiescent current drops from 700µA at 200kHz to 30µA at 12.5kHz, and shutdown current is 3µA when CS is HIGH. Power scales nearly linearly with sample rate because internal analog circuitry (comparator, capacitor array) activates per conversion. Figure 3 in the datasheet confirms ~10× reduction in supply current when lowering throughput from 200kHz to 12.5kHz - a key lever for extending battery life.