Texas Instruments ADS8325IDGKR

Overview

ADS8325IDGKR from Texas Instruments is a 16-bit, SAR-based 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 14.6-bit ENOB at 1 kHz - deployed in isolated data acquisition and battery-powered precision sensing.

For engineers reviewing the ADS8325IDGKR datasheet, ADS8325IDGKR pinout, ADS8325IDGKR application, or ADS8325IDGKR equivalent, key selection considerations include its MSOP-8 package, differential input voltage range (0 to VREF), power-down mode timing (CS/SHDN control), and compatibility with legacy 12-bit ADCs like ADS7816 for system upgrades.

Technical Context

The ADS8325IDGKR implements a capacitive redistribution SAR architecture with integrated sample-and-hold, enabling single-cycle 100 kSPS throughput without pipeline delay. Its differential input stage accepts ±0.3 V to +0.5 V common-mode on –IN and full-scale differential swing up to VREF, with internal CDAC and comparator driving synchronous serial output.

Conversion is clocked externally via DCLOCK (24 kHz–2.4 MHz), with CS/SHDN controlling chip select and shutdown entry/exit. Data appears MSB-first on DOUT synchronized to DCLOCK falling edge, with no latency between conversion completion and first bit output.

Key Specifications

Pinout & Package

ADS8325IDGKR is packaged in an 8-pin MSOP (DGK) with exposed thermal pad internally connected to substrate; pad may be tied to analog ground or left floating but must remain isolated from digital ground.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution, low-power SAR ADC applications.

Compared with ADS8325IDGKR, ADS8326IDGKR simplifies reference design at the cost of higher static current, while ADS8322IBDRBR trades power efficiency for raw speed and requires PCB redesign due to non-pin-compatible control interface.

Availability

ADS8325IDGKR is available at Aetrix Electronics and suitable for battery-operated systems, isolated data acquisition, and remote sensor modules requiring stable component supply with long-term industrial lifecycle support.

Supply support for ADS8325IDGKR 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 ADS8325IDGKR belongs to TI's precision SAR ADC product line, engineered for high-resolution, low-noise, and ultra-low-power data acquisition in portable, isolated, and multi-channel industrial systems.

FAQ

What is the maximum clock frequency supported by the ADS8325IDGKR?

The ADS8325IDGKR supports an external DCLOCK frequency from 24 kHz to 2.4 MHz. At 2.4 MHz, it achieves its full 100 kSPS throughput with 24 clock cycles per conversion. Operation below 24 kHz reduces throughput proportionally, and minimum high/low times must exceed 200 ns for VDD ≥ 4.75 V. The ADS8325IDGKR does not require a fixed duty cycle, easing clock source selection.

Does the ADS8325IDGKR require an external reference voltage?

Yes, the ADS8325IDGKR requires an external reference voltage applied to the REF pin. It accepts any stable reference from 2.5 V to VDD, setting the full-scale input range. Reference input resistance exceeds 5 GΩ when CS = VDD, minimizing loading. The ADS8325IDGKR does not include an internal reference; using an external 2.5 V or 5 V reference directly determines LSB size and noise floor in µV terms.

How does the CS/SHDN pin function on the ADS8325IDGKR?

The CS/SHDN pin on the ADS8325IDGKR serves dual functions: active-low chip select during normal operation, and shutdown enable when driven high. When CS/SHDN is high, the device enters microPower shutdown mode drawing ≤0.2 µA (5 V) or ≤0.1 µA (3 V). Wake-up is immediate upon CS/SHDN transition to low, with tDIS ≤100 ns. This enables precise power gating in duty-cycled sensor systems using the ADS8325IDGKR.

Can the ADS8325IDGKR interface directly with a microcontroller SPI port?

Yes, the ADS8325IDGKR features an SPI/SSI-compatible serial interface with MSB-first, CMOS/LVCMOS-level DOUT and DCLOCK inputs. It requires no additional framing or handshaking - data shifts out synchronously on DCLOCK falling edge. The ADS8325IDGKR is fully compatible with standard microcontroller SPI peripherals configured for mode 0 (CPOL = 0, CPHA = 0), provided load capacitance stays ≤30 pF and timing margins (e.g., tHDO ≤15 ns) are met.

What is the differential input voltage range specification for the ADS8325IDGKR?

The ADS8325IDGKR differential input voltage range is defined as (+IN) – (–IN), with a full-scale range of 0 V to VREF. The –IN pin must remain within –0.3 V to +0.5 V, while +IN must stay within –0.3 V to VDD + 0.3 V (or –IN to –IN + VREF, whichever limit is stricter). Exceeding these ranges degrades linearity and may cause missing codes. This constraint ensures optimal performance when interfacing with instrumentation amplifiers or bridge sensors referenced to local ground.