Texas Instruments TPS2231MRGPR-2

Overview

TPS2231MRGPR-2 from Texas Instruments is a single-slot ExpressCard™ power interface switch that distributes and regulates 3.3 V, 1.5 V, and AUX power rails to ExpressCard|34/|54 sockets with integrated current limiting, thermal protection, and undervoltage lockout. It supports notebook and desktop computers requiring compliant hot-plug power sequencing for PCI Express and USB-based ExpressCards.

For engineers reviewing the TPS2231MRGPR-2 datasheet, TPS2231MRGPR-2 pinout, TPS2231MRGPR-2 application, or TPS2231MRGPR-2 equivalent, key selection criteria include its 24-pin PowerPAD™ HTSSOP package, dual-rail current-limiting (1.3 A @ 3.3VOUT, 650 mA @ 1.5VOUT), PERST/RCLKEN timing coordination, and ExpressCard™ compliance per SLVS536A.

Technical Context

The TPS2231MRGPR-2 implements three independent MOSFET power switches - one each for 3.3VIN→3.3VOUT, 1.5VIN→1.5VOUT, and AUXIN→AUXOUT - each with internal current-sense circuitry, thermal shutdown (trip at 155–165°C), and UVLO thresholds (3.3VIN: 2.6–2.9 V; 1.5VIN: 1.0–1.25 V; AUXIN: 2.6–2.9 V). Its control logic interprets CPPE/CPUSB, SHDN, STBY, and SYSRST to manage power states including Off, Shutdown, No Card, Standby, and Card Inserted.

It features open-drain OC fault reporting, active-low PERST with programmable delay (500 ns assertion, 4–20 ms de-assertion), and bidirectional RCLKEN I/O that synchronizes host clock enable with power-good status. All outputs support soft-start via controlled rise/fall times (0.1–6 ms) and discharge FETs activated during card removal or shutdown.

Key Specifications

Pinout & Package

TPS2231MRGPR-2 uses a 24-pin PowerPAD™ HTSSOP (PWP) package with exposed thermal pad soldered to PCB ground plane for optimal thermal performance (θ_JA = 33.19 mW/°C; P_D = 3153 mW at T_A = 25°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ExpressCard power interface applications.

Compared with TPS2231PWPR, TPS2231MRGPR-2 delivers 4.5× higher thermal power handling and robust hot-swap reliability; compared with TPS2236DAPR, it offers optimized cost and footprint for single-slot implementations without redundant channel logic.

Availability

TPS2231MRGPR-2 is available at Aetrix Electronics and suitable for notebook computers, desktop motherboards, and portable embedded systems requiring stable component supply, ExpressCard™ compliance, and industrial temperature operation.

Supply support for TPS2231MRGPR-2 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 decades of power management innovation.

The TPS2231 product line delivers fully integrated ExpressCard™ power interface solutions designed specifically for seamless, standards-compliant hot-plug power delivery in mobile and desktop computing platforms.

FAQ

What is the primary function of the TPS2231MRGPR-2 in an ExpressCard system?

The TPS2231MRGPR-2 serves as the dedicated power interface switch for single-slot ExpressCard|34 and ExpressCard|54 systems. It manages three independent power rails (3.3V, 1.5V, and AUX), enforces ExpressCard™-mandated sequencing, generates PERST and RCLKEN signals, and provides hardware-level fault protection including overcurrent and thermal shutdown. Its design eliminates external discrete components required for compliant hot-plug operation.

How does the TPS2231MRGPR-2 handle card insertion and removal events?

The TPS2231MRGPR-2 detects card presence via CPPE and CPUSB inputs, which are internally pulled up to AUXIN. Upon card insertion (grounding either input), it transitions from No Card mode to Card Inserted mode, enabling all three power rails with controlled rise times. On removal, discharge FETs activate within milliseconds to safely sink residual charge from 3.3VOUT, 1.5VOUT, and AUXOUT, preventing bus contention or latch-up in the host system.

What are the key timing relationships between RCLKEN and PERST in the TPS2231MRGPR-2?

In the TPS2231MRGPR-2, RCLKEN functions as a hardware-synchronized gate for PERST de-assertion. Once all output rails stabilize within tolerance, the internal discharge FET releases RCLKEN, allowing it to rise (pulled up to AUXIN). This rising edge initiates an internal timer; PERST is then de-asserted (goes high) after a fixed 4–20 ms delay. This ensures PERST remains asserted until both rail stability and host clock readiness are confirmed.

Can the TPS2231MRGPR-2 operate without a 1.5VIN supply?

Yes - the TPS2231MRGPR-2 can operate without 1.5VIN applied. The 1.5V rail is optional and only required when powering ExpressCard modules that need 1.5 V. If 1.5VIN is absent or below its UVLO threshold (1.0–1.25 V), the 1.5VOUT switch remains disabled, but AUXOUT and 3.3VOUT continue functioning normally provided their respective inputs (AUXIN and 3.3VIN) are present and valid.

What thermal considerations apply to the TPS2231MRGPR-2's PowerPAD™ HTSSOP package?

The TPS2231MRGPR-2's 24-pin PowerPAD™ HTSSOP (PWP) package requires the exposed thermal pad to be soldered to a PCB copper pour connected to ground for effective heat dissipation. With proper thermal design (JEDEC low-k board, 2-oz traces), it achieves 33.19 mW/°C derating above 25°C, enabling 3153 mW total power dissipation. Without soldered thermal pad, thermal performance degrades significantly - always follow TI's layout guidelines in SLVS536A.