Texas Instruments TPS65231A2DCA

Overview

TPS65231A2DCA from Texas Instruments is a highly integrated power management IC (PMIC) for digital set-top boxes, featuring one adjustable PWM buck controller (3.3–6.1 V, 500 kHz), two synchronous step-down regulators (0.9–3.3 V, 1 MHz, 3-A each), dual 1-A USB power switches with overcurrent protection, and a dual-input supply voltage supervisor with brownout and thermal warning flags. It operates from a 10.8–22-V input and delivers precise rail sequencing in satellite STB and xDSL modem applications.

For engineers reviewing the TPS65231A2DCA datasheet, TPS65231A2DCA pinout, TPS65231A2DCA application, or TPS65231A2DCA equivalent, key selection considerations include its triple-buck architecture with independent enable control, I²C/parallel interface flexibility, integrated 1-A USB switches with fault flagging, thermal shutdown at 160°C, and HTSSOP-48 package with thermally enhanced layout for high-density STB designs.

Technical Context

The TPS65231A2DCA integrates three independent DC-DC conversion blocks: BUCK1 is a high-voltage PWM controller (VIN = 10.8–22 V, VOUT = 3.3–6.1 V, fSW = 500 kHz); BUCK2 and BUCK3 are low-voltage synchronous buck regulators (VINB = 4.75–6.1 V, VOUT = 0.9–3.3 V, fSW = 1 MHz, 3-A continuous). Each includes Type III compensation, programmable current limit via external TRIP resistor, and hiccup-mode overcurrent protection.

It supports dual control modes: parallel I/O (EN_BCKx, EN_USBx pins) or I²C (address selectable via I2C_ADD pin), with USBFLAG2/nINT serving as shared interrupt/fault output. The supply voltage supervisor monitors VMON1 (3.3-V rail) and VMON2 (scalable via divider), asserting nRST (≥180 ms) and nBOR/nHOT on undervoltage (<9.3 V) or thermal warning (>120°C).

Key Specifications

Pinout & Package

TPS65231A2DCA is housed in a 48-pin HTSSOP (DCA) package with exposed thermal pad. Pin functions are validated per TI SLVSA10A datasheet, including dedicated enable, feedback, compensation, bootstrap, switching, ground, and monitoring terminals for all three buck stages, dual USB switches, and SVS inputs/outputs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power management IC applications.

Compared with TPS65231A2DCA, TPS65230A2DCA offers identical power architecture but reduced USB current capability, while TPS65217CZQW shifts focus toward portable applications with added analog functions and incompatible packaging - neither serves as a pin-compatible upgrade or direct substitute for STB/modem use cases.

Availability

TPS65231A2DCA is available at Aetrix Electronics and suitable for digital set-top box, xDSL/cable modem, and home gateway applications requiring stable component supply, long-term lifecycle support, and traceable sourcing for volume production.

Supply support for TPS65231A2DCA 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 power management technologies, with decades of expertise in high-reliability power solutions for consumer and communications infrastructure.

The TPS65231A2DCA belongs to TI's digital STB PMIC product line, designed specifically to consolidate power delivery, USB control, and system supervision into a single IC for satellite and broadband residential equipment.

FAQ

What is the maximum continuous output current supported by each buck regulator in the TPS65231A2DCA?

The TPS65231A2DCA supports 3-A continuous output current for both BUCK2 and BUCK3 (0.9–3.3 V range), and BUCK1 delivers up to 3-A depending on input/output voltage differential and thermal design. All three regulators include cycle-by-cycle overcurrent protection and hiccup-mode recovery to sustain safe operation under sustained overload.

How does the TPS65231A2DCA handle power-up sequencing across its three buck regulators?

The TPS65231A2DCA enables flexible power-up sequencing via EN_BCK1, EN_BCK2, and EN_BCK3 pins. Connecting them directly to V3P3 yields default order (BUCK1 → BUCK2 → BUCK3, ≥1.5 ms spacing); adding capacitors to ground creates custom delays (0.2 ms/nF). In I²C mode, sequencing is controlled by writing to ENABLE register bits with identical timing constraints.

Can the TPS65231A2DCA be used in I²C mode and parallel I/O mode simultaneously?

No - the TPS65231A2DCA operates exclusively in one control mode at a time. I²C mode is enabled only when the USBFLAG2/nINT pin has a pull-up resistor connected to ≥4.8 V (e.g., V6V); otherwise, it defaults to parallel I/O mode. Mixing control signals causes undefined behavior and is not supported.

What is the function of the nBOR/nHOT pin on the TPS65231A2DCA, and how does it differ from the nRST pin?

The nBOR/nHOT pin is an open-drain output that asserts low on either input brownout (<9.3 V) or thermal warning (>120°C), giving the host processor time to save data before shutdown. In contrast, nRST is a dedicated reset output triggered solely by SVS monitoring (VMON1/VMON2 undervoltage) and holds low for ≥180 ms - it has no thermal or brownout role.

Does the TPS65231A2DCA support external synchronization of its switching frequency?

No - the TPS65231A2DCA does not support external clock synchronization. BUCK1 operates at a fixed 500 kHz, and BUCK2/BUCK3 operate at a fixed 1 MHz. Frequency is internally generated and not adjustable via external components or control registers.