Texas Instruments TPS2224DBR

Overview

TPS2224DBR from Texas Instruments is a dual-slot CardBus power-interface switch for serial PCMCIA controllers, integrating independent 3.3 V/5 V/12 V switching for two card sockets. It delivers up to 750 mA per xVCC output and 100 mA per xVPP output, features break-before-make switching, thermal shutdown at 135°C, and supports TTL-compatible serial control (DATA/CLOCK/LATCH). It is used in legacy notebook computers and industrial PC Card host systems requiring compliant power sequencing.

For engineers reviewing the TPS2224DBR datasheet, TPS2224DBR pinout, TPS2224DBR application, or TPS2224DBR equivalent, key selection criteria include its dual-slot VCC/VPP independence, 24-pin HTSSOP package with exposed thermal pad, 140-µA quiescent current, and support for PC Card Standard-compliant overcurrent reporting via open-drain OC pin.

Technical Context

The TPS2224DBR implements a serially controlled, dual-channel power-switch architecture with separate high-side switches for AVCC/BVCC (3.3 V/5 V) and AVPP/BVPP (3.3 V/5 V/12 V), each featuring internal current limiting and thermal protection. Its control logic accepts 3-wire serial commands (DATA, CLOCK, LATCH) to configure individual slot outputs without standby-mode pins.

It integrates UVLO on 3.3 V and 5 V inputs (trip points at 2.7 V and 2.5 V respectively), power-on reset (POR) asserting internal RESET below 1.7 V, and independent SHDN pin enabling asynchronous Hi-Z of all switches. The device does not support 12 V on TPS2223 but fully supports it on TPS2224DBR and TPS2226.

Key Specifications

Pinout & Package

TPS2224DBR is housed in a 24-pin HTSSOP (PowerPAD™) package (DB-24) with exposed thermal pad for enhanced power dissipation (890 mW at TA ≤ 25°C). Pin 1 is top-left corner; pin numbering follows standard counter-clockwise sequence.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-slot PCMCIA power-switching applications.

Compared with TPS2226DB and TPS2214DB, the TPS2224DBR offers optimal balance of 12 V support, compact 24-pin HTSSOP packaging, and full serial + SHDN control - making it the preferred choice for new industrial and legacy-compliant notebook host designs requiring dual-slot flexibility.

Availability

TPS2224DBR is available at Aetrix Electronics and suitable for notebook computers, bar code scanners, and digital cameras requiring stable component supply with long-term lifecycle support and traceable sourcing.

Supply support for TPS2224DBR 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management technologies.

The TPS222x family was designed specifically for PCMCIA-compliant dual-slot CardBus host controllers, addressing the need for integrated, standards-compliant power switching with minimal external components and robust fault handling.

FAQ

What is the maximum continuous output current supported by TPS2224DBR on its xVCC and xVPP channels?

The TPS2224DBR supports up to 750 mA per xVCC channel (AVCC/BVCC) at TJ = 100°C and up to 100 mA per xVPP channel (AVPP/BVPP) under the same condition. These values are specified in the recommended operating conditions table and reflect steady-state current limits before thermal or current-limit protection activates. The TPS2224DBR uses internal current sensing and thermal shutdown to enforce these limits reliably.

Does TPS2224DBR support 12 V on both AVPP and BVPP outputs simultaneously?

Yes, the TPS2224DBR supports 12 V on both AVPP (pin 8) and BVPP (pin 19) outputs. This is confirmed by the Terminal Functions table and functional block diagram in the SLVS317 datasheet, which explicitly list 12 V capability for both xVPP outputs - unlike the TPS2223, which omits 12 V entirely. The two 12 V input pins (7 and 20) must be externally connected to enable this functionality.

How does the OC (overcurrent) pin on TPS2224DBR function, and what external components are required?

OC is an open-drain output that pulls low during overcurrent events on any xVCC or xVPP channel. It requires an external pullup resistor (typically 4.7 kΩ to 3.3 V or 5 V) to generate a valid logic-high signal when idle. The TPS2224DBR asserts OC within 10 µs for xVCC faults and 3 µs for xVPP faults, enabling fast system-level fault isolation. No additional filtering or debouncing is required for basic detection.

Can TPS2224DBR operate with only the 3.3 V supply, or are 5 V and 12 V inputs mandatory?

The 3.3 V supply (pins 13/14) is mandatory for all TPS2224DBR operation - it powers internal logic and enables 3.3 V xVCC/xVPP outputs. The 5 V supply (pins 1/2/24) is required only if 5 V outputs are used; the 12 V supply (pins 7/20) is required only if 12 V xVPP outputs are enabled. Unused supplies may be left unconnected, but their corresponding outputs will remain inactive.

What is the purpose of the SHDN pin on TPS2224DBR, and how does it interact with serial control?

The SHDN pin provides asynchronous, hardware-level shutdown: pulling it low forces all xVCC and xVPP outputs into Hi-Z state regardless of serial register contents. It functions identically to the serial D8 command but operates independently of clock/data timing. This allows immediate power isolation during emergency conditions or mechanical card ejection, complementing the programmable serial interface for flexible system-level power management in the TPS2224DBR.