Texas Instruments ADS7229IPWR

Overview

ADS7229IPWR from Texas Instruments is a low-power, 12-bit, 1-MSPS successive approximation register (SAR) analog-to-digital converter with unipolar input range (0 V to V_REF), built-in conversion clock, and SPI/DSP-compatible serial interface. It operates from 2.7 V to 5.5 V analog supply, delivers ±0.5 LSB max INL/DNL, and supports daisy-chain mode for multi-ADC systems in industrial data acquisition.

For engineers reviewing the ADS7229IPWR datasheet, ADS7229IPWR pinout, ADS7229IPWR application, or ADS7229IPWR equivalent, key selection criteria include its 1 MSPS throughput at 3–5.5 V, 13.7 mW power at 3 V/1 MSPS, programmable EOC/INT polarity, global CONVST control, and TSSOP-16 package compatibility with industrial temperature range (–40°C to +85°C).

Technical Context

The ADS7229IPWR implements a capacitor-based SAR architecture with inherent sample-and-hold, enabling precise DC and AC performance without external components. Its internal 21–24.5 MHz conversion clock eliminates need for external timing sources while supporting up to 50 MHz SCLK for high-speed serial readout.

It features dual power domains (+VA for analog, +VBD for I/O), programmable status output (EOC/INT/CDI), frame sync/chip select (FS/CS), and global CONVST that initiates conversion independent of CS state-enabling deterministic timing in real-time control loops.

Key Specifications

Pinout & Package

TSSOP-16 package with exposed thermal pad (not electrically connected); pin 1 marked by dot; compatible with standard surface-mount reflow profiles per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7230IPWR, ADS7229IPWR removes MUX overhead for single-input systems, reducing latency and firmware complexity; versus ADS8329IPWR, it trades 4-bit resolution for 2× speed, 40% lower power, and integrated clocking-making it optimal for cost-sensitive, high-throughput industrial sensing.

Availability

ADS7229IPWR is available at Aetrix Electronics and suitable for industrial process control, medical instrumentation, magnetometer signal conditioning, and automated test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADS7229IPWR 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, embedded processing, and connectivity technologies with over 90 years of innovation in precision signal chain solutions.

The ADS7229 belongs to TI's low-power, high-speed SAR ADC family designed for industrial, medical, and test equipment where accuracy, speed, and power efficiency must coexist without compromise.

FAQ

What is the maximum sampling rate of the ADS7229IPWR under 3V analog supply conditions?

The ADS7229IPWR achieves a maximum sampling rate of 1 MSPS when the analog supply (+VA) is between 3.0 V and 5.5 V. At 2.7 V ≤ +VA < 3.0 V, the maximum rate drops to 900 kSPS due to internal clock limitations. This behavior is specified in the Electrical Characteristics table for 2.7–3.6 V operation and confirmed in the Timing Characteristics section for 1.8 V I/O conditions. The ADS7229IPWR maintains full 12-bit performance across both ranges.

Does the ADS7229IPWR require an external reference voltage, or can it operate with an internal reference?

The ADS7229IPWR requires an external reference voltage applied between REF+ and REF– pins; it does not include an internal reference. The reference input accepts 0.3 V to +VA, with typical use cases at 2.5 V (for 3 V supplies) or 5 V (for 5 V supplies). Reference input resistance is 40 kΩ, and the device specifies tight gain error (±0.1% FSR) and drift (±0.5 ppm/°C), making it compatible with precision external references like the REF5025 or REF6025. The ADS7229IPWR relies entirely on this external source to define its full-scale range.

How does the global CONVST feature of the ADS7229IPWR improve synchronization in multi-ADC systems?

The global CONVST input on the ADS7229IPWR initiates sampling simultaneously across all devices sharing the same CONVST signal-even if their FS/CS lines are asserted at different times. This decouples conversion triggering from SPI bus arbitration, eliminating inter-device skew caused by CS propagation delays or software-driven command sequencing. In systems with multiple ADS7229IPWR units, a single FPGA or MCU GPIO can drive CONVST to achieve <1 ns practical skew, enabling coherent sampling for phasor measurement units (PMUs) or multi-axis motion controllers. The ADS7229IPWR datasheet confirms this behavior is independent of CS state.

What power-down modes are supported by the ADS7229IPWR, and what are their typical current draws?

The ADS7229IPWR supports three power-down modes: Deep Power-Down (1 µA typical), Nap Power-Down (0.5 µA typical), and Auto Nap Power-Down (automatically entered after conversion completes). These modes are controlled via SPI commands and reduce total supply current from 7.0 mA (active, 5 V) to microampere levels. Deep Power-Down disables the internal clock and all circuitry except wake-up logic; Nap retains bias states for faster wake-up (<1 µs). All modes maintain register contents and are fully specified over –40°C to +85°C. The ADS7229IPWR datasheet lists these values in the POWER-SUPPLY REQUIREMENTS table under "Deep power-down mode" and "Nap or Auto Nap mode" rows.

Can the ADS7229IPWR interface directly with a 1.8V microcontroller SPI port without level shifting?

Yes, the ADS7229IPWR supports direct interfacing with 1.8 V microcontrollers because its +VBD (I/O supply) accepts 1.65 V to 5.5 V, and its digital inputs (VIH/VIL) are referenced to +VBD-not +VA. When +VBD = 1.8 V, VIH = 0.65 × 1.8 V = 1.17 V (min) and VIL = 0.35 × 1.8 V = 0.63 V (max), matching standard 1.8 V logic thresholds. Output VOH/VOL also comply: VOH ≥ 1.2 V and VOL ≤ 0.4 V into 100 µA load. Therefore, no level shifter is needed between a 1.8 V MCU and the ADS7229IPWR when +VBD is set to 1.8 V, as verified in the DIGITAL INPUT/OUTPUT section of the datasheet.