Texas Instruments ADS8325IDRBRG4

Overview

ADS8325IDRBRG4 from Texas Instruments is a 16-bit, SAR analog-to-digital converter with differential input, SPI/SSI-compatible serial interface, and microPower operation (4.5 mW at 100 kSPS, 1 mW at 10 kSPS). It supports 2.7V–5.5V supply, 2.5V–VDD reference, ±1.5 LSB typical INL, and 100 kSPS throughput - used in isolated data acquisition and battery-powered precision sensing.

For engineers reviewing the ADS8325IDRBRG4 datasheet, ADS8325IDRBRG4 pinout, ADS8325IDRBRG4 application, or ADS8325IDRBRG4 equivalent, key selection criteria include differential input noise performance (3 LSB_PP), power-down current (0.2 µA at 5 V), MSOP-8/SON-8 package compatibility, and SPI timing compliance with t_CONV ≤ 666.7 µs.

Technical Context

The ADS8325IDRBRG4 implements a capacitive redistribution SAR architecture with integrated sample-and-hold, enabling single-cycle 16-bit conversion without pipeline delay. Its differential analog front-end accepts inputs from –0.3 V to +0.5 V on –IN and up to V_DD + 0.3 V on +IN, with full-scale range defined by external reference voltage.

It uses a synchronous serial interface clocked by DCLOCK (24 kHz–2.4 MHz), outputs MSB-first straight-binary data on DOUT, and enters low-power shutdown when CS/SHDN is high. Conversion timing is deterministic: 16 clock cycles for conversion plus 4.5 cycles for sampling, totaling ≤22 clock cycles per 100 kSPS cycle.

Key Specifications

Pinout & Package

ADS8325IDRBRG4 is packaged in an 8-pin SON (DRB) package measuring 3 mm × 3 mm × 0.9 mm, with exposed thermal pad internally connected to substrate (recommended to connect to analog ground).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with ADS8326IDRBT, ADS8325IDRBRG4 offers lower power and external reference flexibility; compared with ADS8322IDRBT, it provides smaller footprint and simpler digital interface - making ADS8325IDRBRG4 optimal for modern microcontroller-based, low-power, isolated DAQ systems.

Availability

ADS8325IDRBRG4 is available at Aetrix Electronics and suitable for battery-operated sensors, isolated industrial data acquisition, and remote vibration monitoring requiring stable component supply and long-term manufacturability.

Supply support for ADS8325IDRBRG4 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 company headquartered in Dallas, Texas, specializing in analog and embedded processing technologies with over 50 years of precision data converter innovation.

The ADS8325IDRBRG4 belongs to TI's precision SAR ADC product line, designed specifically for high-resolution, low-power, and isolated signal acquisition in portable instrumentation, industrial automation, and condition monitoring systems.

FAQ

What is the maximum clock frequency supported by ADS8325IDRBRG4?

The ADS8325IDRBRG4 supports a DCLOCK input frequency from 24 kHz to 2.4 MHz. At 2.4 MHz, the device achieves its full 100 kSPS throughput with 24 clock cycles per conversion. Exceeding 2.4 MHz violates timing specifications and may cause data corruption or increased INL error. The minimum clock period must maintain ≥200 ns high/low times when VDD ≥ 4.75 V.

Does ADS8325IDRBRG4 require an external reference voltage?

Yes, ADS8325IDRBRG4 requires an external reference voltage applied to the REF pin. It accepts any stable voltage from 2.5 V to VDD (2.7 V–5.5 V). The reference directly defines full-scale range and LSB size: e.g., 5 V ref = 76.3 µV/LSB; 2.5 V ref = 38.15 µV/LSB. Internal reference is not integrated - using an external precision reference (e.g., REF5025) ensures optimal INL and drift performance.

How does the differential input of ADS8325IDRBRG4 improve noise immunity?

The ADS8325IDRBRG4 differential input (+IN/–IN) rejects common-mode noise by amplifying only the voltage difference between pins. When –IN is tied to a clean local or remote ground (within –0.3 V to +0.5 V range), noise coupled equally to both traces cancels out. This is especially effective in noisy industrial environments or long-sensor-cable applications, improving effective SNR by up to 20 dB versus single-ended configurations - confirmed by –91 dB SINAD at 1 kHz with 5 V reference.

Can ADS8325IDRBRG4 operate from a 3.3 V supply?

Yes, ADS8325IDRBRG4 is fully specified for 2.7 V–5.5 V operation. At 3.3 V supply, it delivers 100 kSPS throughput, ±1.5 LSB INL (typ), and 1.5 mW power dissipation. Digital I/O remains LVCMOS-compatible: VIH ≥ 2.0 V, VIL ≤ 0.8 V. Reference voltage must be ≤3.3 V (e.g., 2.5 V or 3.0 V), and full-power bandwidth reduces to 4 kHz - sufficient for most sensor and control applications.

What is the function of the CS/SHDN pin on ADS8325IDRBRG4?

The CS/SHDN pin on ADS8325IDRBRG4 serves dual functions: when pulled low, it acts as chip select enabling serial communication; when driven high, it places the device into ultra-low-power shutdown mode drawing only 0.2 µA (at 5 V) or 0.1 µA (at 3 V). This feature enables precise power gating in battery-powered systems - for example, waking the ADS8325IDRBRG4 only during scheduled sampling intervals to achieve multi-year operational life on coin-cell batteries.