Texas Instruments TPS2231MRGPR

Overview

TPS2231MRGPR 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 expansion cards.

For engineers reviewing the TPS2231MRGPR datasheet, TPS2231MRGPR pinout, TPS2231MRGPR application, or TPS2231MRGPR equivalent, key selection criteria include its 24-pin PowerPAD™ HTSSOP package, 1.3 A 3.3VOUT continuous current rating, 650 mA 1.5VOUT output, AUXOUT support up to 275 mA, and ExpressCard-compliant PERST/RCLKEN timing control logic.

Technical Context

The TPS2231MRGPR implements three independent MOSFET power switches (3.3VIN→3.3VOUT, 1.5VIN→1.5VOUT, AUXIN→AUXOUT), each with internal current-limit sensing, thermal shutdown, and discharge FETs. Its control logic interprets CPPE/CPUSB card-present signals, SHDN/STBY mode inputs, and SYSRST to manage rail sequencing and PERST assertion per ExpressCard specification.

It features dual-mode operation: Card Inserted mode enables all outputs upon detection of CPPE or CPUSB low; Standby mode maintains AUXOUT while disabling 3.3VOUT and 1.5VOUT. UVLO thresholds (3.3VIN: 2.6–2.9 V; 1.5VIN: 1.0–1.25 V; AUXIN: 2.6–2.9 V) ensure stable turn-on and prevent brownout operation.

Key Specifications

Pinout & Package

TPS2231MRGPR uses a 24-pin PowerPAD™ HTSSOP (PWP) package with exposed thermal pad for enhanced heat dissipation. Pin 1 is located at top-left corner (marking dot adjacent); pin numbering proceeds counterclockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS2231PW, the TPS2231MRGPR offers 4.5× higher power dissipation capability and superior thermal performance in the same footprint; versus TPS2236DAP, it provides cost-optimized single-slot functionality without redundant channel circuitry.

Availability

TPS2231MRGPR is available at Aetrix Electronics and suitable for notebook computers, desktop ExpressCard adapters, and digital camera docking stations requiring stable component supply, long-term lifecycle support, and ExpressCard-compliant power sequencing.

Supply support for TPS2231MRGPR 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 over 50 years of innovation in high-reliability interface solutions.

The TPS2231MRGPR belongs to TI's ExpressCard power interface product line, engineered specifically to replace discrete MOSFET-based power solutions in host systems complying with PCMCIA ExpressCard 1.0/2.0 standards.

FAQ

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

The TPS2231MRGPR serves as the dedicated power interface switch for single-slot ExpressCard|34 and ExpressCard|54 hosts. It delivers and sequences 3.3 V, 1.5 V, and AUX power rails to the card socket, enforces ExpressCard-compliant timing for PERST and RCLKEN signals, and provides integrated overcurrent and thermal protection. The TPS2231MRGPR replaces multiple discrete components with a single IC that meets all functional and timing requirements specified in the ExpressCard standard.

Does the TPS2231MRGPR support both PCI Express and USB-based ExpressCard modules?

Yes, the TPS2231MRGPR supports both interface types through dedicated CPPE (Card Present PCI Express) and CPUSB (Card Present USB) inputs. These TTL-compatible pins detect card insertion via ground connection and initiate appropriate rail enable sequences. The TPS2231MRGPR generates PERST - required only for PCI Express modules - while maintaining full compatibility with USB-only cards that ignore PERST. Its AUXOUT rail remains active in Standby mode for both interface types.

How does the TPS2231MRGPR handle overcurrent conditions on its output rails?

The TPS2231MRGPR monitors current on all three output rails (3.3VOUT, 1.5VOUT, AUXOUT) using internal sense circuitry. Upon detecting an overcurrent event, it asserts the open-drain OC pin low after a deglitch delay of 6–20 ms. Simultaneously, it limits output current to steady-state values of 2.5 A (3.3VOUT), 1.3 A (1.5VOUT), and 600 mA (AUXOUT). The device does not latch off; recovery occurs automatically once the overload condition clears and junction temperature falls below hysteresis threshold.

What are the key timing parameters governing PERST assertion and de-assertion in the TPS2231MRGPR?

The TPS2231MRGPR asserts PERST (drives low) within 500 ns of any output voltage falling outside tolerance (3.3VOUT < 2.7 V, AUXOUT < 2.7 V, 1.5VOUT < 1.2 V). De-assertion (transition to high) occurs 4–20 ms after all rails rise into tolerance and RCLKEN transitions high. This timing aligns precisely with ExpressCard specification requirements. Additionally, SYSRST can force immediate PERST assertion regardless of rail status - enabling controlled warm resets without power cycling.

Can the TPS2231MRGPR operate without a 1.5VIN supply present?

Yes, the TPS2231MRGPR can operate with 1.5VIN absent, provided AUXIN and 3.3VIN are present. In this configuration, the 1.5VOUT switch remains disabled, but 3.3VOUT and AUXOUT remain fully functional. The device enters Standby mode if STBY is asserted, or No Card mode if no CPPE/CPUSB signal is detected. However, full ExpressCard compliance requires 1.5VIN for USB-based cards; operation without it is valid only for PCI Express-only use cases where 1.5 V is unused.