Texas Instruments TLV2556IDWR

Overview

TLV2556IDWR from Texas Instruments is a low-power 12-bit successive-approximation analog-to-digital converter (SAR ADC) with integrated 14-channel analog multiplexer, on-chip 2.048-V/4.096-V selectable internal reference, and SPI-compatible serial interface. It delivers up to 200-kSPS throughput at 5 V and 150-kSPS at 3 V, features inherent sample-and-hold, programmable MSB/LSB-first output, and operates across –40°C to +85°C for industrial data acquisition.

For engineers reviewing the TLV2556IDWR datasheet, TLV2556IDWR pinout, TLV2556IDWR application, or TLV2556IDWR equivalent, key selection considerations include its 11 external analog input channels plus 3 internal self-test voltages, dual-reference programmability, INT/EOC status pin configuration, and SOIC-20 package compatibility with TSSOP-20 footprints in space-constrained embedded systems.

Technical Context

The TLV2556IDWR implements a switched-capacitor SAR architecture with an internal oscillator (2.56–4.15 MHz), differential high-impedance reference inputs (REF+/REF−), and configurable conversion status output (INT or EOC). Its control logic accepts 4-bit address/command via DATA IN and shifts out 12-bit conversion results via DATA OUT synchronized to I/O CLOCK.

It integrates an 11-channel analog multiplexer (AIN0–AIN10), three built-in self-test modes (0, 2048, 4095 codes), and supports unipolar/bipolar operation. Configuration registers (CFGR1, CFGR2) enable programmable power-down, output data length, and reference source selection-enabling flexible integration into microcontroller-based sensor interfaces without external timing or reference components.

Key Specifications

Pinout & Package

TLV2556IDWR is packaged in a 20-pin SOIC (DW) with 7.50 mm × 12.80 mm body size, lead pitch of 1.27 mm, and surface-mount footprint compatible with JEDEC MS-013AC. Thermal resistance RθJA is 66.0°C/W, supporting convection-cooled PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and TLV2548IPW, TLV2556IDWR provides the highest channel count (11) and integrated reference among TI's pin-compatible 20-pin SAR ADC family, making it optimal for multi-sensor industrial and portable systems requiring minimal external components.

Availability

TLV2556IDWR is available at Aetrix Electronics and suitable for industrial process control, portable data logging, and battery-powered instrumentation requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for TLV2556IDWR 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 industrial-grade IC design.

The TLV2556IDWR belongs to TI's TLV25xx low-power SAR ADC product line, engineered for high-resolution sensing in resource-constrained, battery-operated, and thermally demanding applications where integration, accuracy, and supply flexibility are critical.

FAQ

What is the maximum sampling rate of the TLV2556IDWR under recommended operating conditions?

The TLV2556IDWR achieves up to 200 kSPS at VCC = 4.5–5.5 V with I/O CLOCK = 15 MHz, and 150 kSPS at VCC = 2.7–3.6 V with I/O CLOCK = 10 MHz. Conversion time is determined by internal oscillator frequency (2.56–4.15 MHz) and fixed at 13.5 × (1/fOSC) + 25 ns, ensuring deterministic timing for real-time control loops. TLV2556IDWR maintains this rate across its full –40°C to +85°C operating range.

Does the TLV2556IDWR require an external reference voltage, or can it operate with its internal reference?

The TLV2556IDWR can operate with either its internal 2.048-V or 4.096-V reference (selected via CFGR2), eliminating the need for external reference ICs. When using the internal reference, REF– must be connected to analog GND, and a 0.1-μF capacitor is required between REF+ and REF–. External references are supported but require additional decoupling and drive capability verification. TLV2556IDWR's internal reference exhibits ±50 ppm/°C temperature coefficient, enabling stable full-scale accuracy in industrial environments.

How many analog input channels does the TLV2556IDWR support, and what are their functions?

The TLV2556IDWR supports 11 external analog input channels (AIN0 through AIN10) and three internal self-test voltages (0 V, VREF+/2, and VREF+), selectable via 4-bit address input. The on-chip 14-channel multiplexer routes one selected input to the SAR core per conversion cycle. All 11 external inputs are high-impedance (≥500 Ω) with leakage current ≤±1 µA, allowing direct connection to passive sensors and resistive dividers without buffering. TLV2556IDWR's channel mapping is defined in Configuration Register 1 and supports sequential or random access.

What is the purpose of the INT/EOC pin on the TLV2556IDWR, and how is it configured?

The INT/EOC pin (Pin 19) serves as a programmable status indicator: configured as INT, it asserts a low pulse upon conversion completion to trigger MCU interrupts; configured as EOC, it holds low until data is ready for readout. Configuration is controlled via CFGR1 bits. The pin operates in open-drain mode and requires an external pull-up. Timing is tightly coupled to I/O CLOCK edges-INT clears on the next rising I/O CLOCK, while EOC remains asserted until CS goes high. TLV2556IDWR's dual-mode flexibility simplifies integration with both interrupt-driven and polling-based firmware architectures.

Is the TLV2556IDWR compatible with standard SPI interfaces, and what are its timing requirements?

Yes, the TLV2556IDWR implements an SPI-compatible serial interface with CPOL = 0 and CPHA = 0, supporting I/O CLOCK frequencies up to 15 MHz (at VCC = 4.5–5.5 V) and 10 MHz (at VCC = 2.7–3.6 V). It requires precise setup/hold times: DATA IN must be valid ≥12 ns before I/O CLOCK rising edge (tsu1), and CS must go low ≥25 ns before the first I/O CLOCK edge (tsu2). TLV2556IDWR's timing is fully documented in Sections 6.9 and 6.10 of its datasheet, including propagation delays (e.g., td1 = 28 ns) and transition times (tt1 = 1 µs), ensuring reliable interfacing with common microcontrollers.