Texas Instruments ADS1625IPAPRG4

Overview

ADS1625IPAPRG4 from Texas Instruments is an 18-bit, 1.25MSPS delta-sigma analog-to-digital converter (ADC) optimized for high-fidelity data acquisition in scientific instrumentation and medical imaging systems. It delivers 93dB SNR, −101dB THD, and 103dB SFDR at 10kHz input, with linear-phase digital filtering up to 615kHz bandwidth and ±0.0025dB passband ripple. Its parallel 18-bit DOUT interface directly connects to TMS320C6000 DSPs under +5V AVDD, +3V DVDD, and +2.7V to +5.25V IOVDD supplies.

For engineers reviewing the ADS1625IPAPRG4 datasheet, ADS1625IPAPRG4 pinout, ADS1625IPAPRG4 application, or ADS1625IPAPRG4 equivalent, key selection considerations include its 18-bit resolution at 1.25MSPS, on-chip reference selectability, adjustable analog power dissipation (150–515mW), out-of-range monitoring via OTR pin, and TQFP-64 PowerPAD™ package compatibility with high-density PCB layouts.

Technical Context

The ADS1625IPAPRG4 employs a stable 2-1-1 pipelined delta-sigma modulator sampling at 40MSPS (fCLK = 40MHz), followed by a low-ripple, linear-phase decimation filter that outputs 1.25MSPS words with 615kHz −3dB bandwidth. Its differential input architecture measures VIN = (AINP − AINN) against VREF = (VREFP − VREFN), supporting full-scale input of ±1.467VREF (±4.4V at 3V reference).

It features dual supply domains: analog (AVDD = 4.75–5.25V), digital core (DVDD = 2.7–3.3V), and I/O (IOVDD = 2.7–5.25V), enabling logic-family flexibility. Power control is implemented via external RBIAS resistor (setting analog current) and dedicated PD pin for full circuit shutdown (5mW standby).

Key Specifications

Pinout & Package

ADS1625IPAPRG4 is housed in a thermally enhanced HTQFP-64 (PAP) package with PowerPAD™ exposed thermal pad, optimized for high-power ADC operation and PCB heat dissipation. Pin count is 64, with 18-bit parallel data bus, dedicated control lines, and separate analog/digital ground/supply terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed, high-precision ADC applications.

Compared with ADS1626IPAPR, ADS1625IPAPRG4 removes FIFO logic to reduce latency and power; compared with ADS1605IPAPT, it trades 3.2× lower sample rate for 2-bit higher resolution and 5dB SNR improvement-making it optimal for fidelity-critical, moderate-bandwidth measurement systems.

Availability

ADS1625IPAPRG4 is available at Aetrix Electronics and suitable for scientific instrumentation, automated test equipment, and medical imaging systems requiring stable component supply, long-term lifecycle support, and traceable sourcing for Class II medical and aerospace-grade BOMs.

Supply support for ADS1625IPAPRG4 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 leadership in precision data converters and signal chain solutions.

The ADS1625IPAPRG4 belongs to TI's high-performance delta-sigma ADC family designed specifically for demanding measurement applications where SNR, SFDR, and passband flatness are critical-targeting scientific, medical, and industrial test systems.

FAQ

What is the maximum clock frequency supported by ADS1625IPAPRG4?

The ADS1625IPAPRG4 supports a master clock (CLK) frequency from 1MHz to 50MHz. At the nominal 40MHz clock, it achieves its specified 1.25MSPS output data rate and full performance (93dB SNR, −101dB THD). Operation above 40MHz does not increase data rate but may affect timing margins and power consumption.

Does ADS1625IPAPRG4 include an internal voltage reference?

Yes, ADS1625IPAPRG4 includes a selectable internal 3.0V reference. When REFEN is driven low, the internal reference activates (VREFP ≈ 4.0V, VREFN ≈ 1.0V, VMID ≈ 2.5V), eliminating the need for external reference components in many applications while maintaining 50ppm/°C drift specification.

How does the RBIAS pin affect power consumption in ADS1625IPAPRG4?

The RBIAS pin connects to an external resistor that sets the analog supply current (IAVDD). With RBIAS = 37kΩ, IAVDD is typically 105mA (REFEN = high) or 135mA (REFEN = low), yielding 515mW total dissipation. Increasing RBIAS to 60kΩ reduces IAVDD to ~85mA, lowering power to ~425mW-enabling thermal optimization without sacrificing AC performance.

Is ADS1625IPAPRG4 pin-compatible with ADS1626IPAPR?

Yes, ADS1625IPAPRG4 and ADS1626IPAPR share identical pinout, package (HTQFP-64), and supply requirements. The only difference is that pins FIFO_LEV[2:0] (46–48) are No Connect (NC) on ADS1625IPAPRG4 and functional on ADS1626IPAPR. All other signals-including DOUT[17:0], DRDY, PD, CLK, and reference pins-are functionally and physically identical.

What is the purpose of the OTR pin on ADS1625IPAPRG4?

The OTR (Out-of-Range) pin on ADS1625IPAPRG4 is an active-high digital output that asserts when either AINP or AINN exceeds the absolute input voltage limits (−0.1V to 4.7V) or when the differential input exceeds ±1.467VREF. It provides immediate hardware-level fault indication for system-level overvoltage protection and data validity checking.