Texas Instruments TPS2224ADB

Overview

TPS2224ADB from Texas Instruments is a dual-slot CardBus™ power-interface switch IC designed for controlled 3.3 V, 5 V, and 12 V distribution to two PC Card sockets. It integrates independent VCC/VPP switching, break-before-make logic, thermal shutdown (135°C), fast current-limit response (≤10 µs), and 140-µA typical quiescent current. Used in notebook computers and CableCARD™ host systems requiring compliant PC Card power management.

For engineers reviewing the TPS2224ADB datasheet, TPS2224ADB pinout, TPS2224ADB application, or TPS2224ADB equivalent, this page delivers verified functional specifications, validated dual-slot power-switching behavior, confirmed HTSSOP-24 package mapping, and real-world timing and protection parameters aligned with PC Card Standard compliance.

Technical Context

The TPS2224ADB implements two fully independent power-switch channels (AVCC/AVPP and BVCC/BVPP), each supporting 3.3 V, 5 V, and - uniquely among its family - 12 V VPP output. Its serial control interface (CLOCK/DATA/LATCH) enables programmable slot enable/disable sequencing with propagation delays as low as 0.26 ms (xVPP rise) and 0.3 ms (xVCC turn-on).

It features integrated UVLO (2.4–2.9 V on 3.3V pin; 2.3–2.8 V on 5V pin), POR-driven internal RESET assertion below 1.7 V, and open-drain OC reporting with 10 mA sink capability. Thermal trip (135°C) and hysteresis (10°C) are hardware-defined; current limits are internally set - 1 A steady-state for xVCC, 100 mA for xVPP - and not user-adjustable.

Key Specifications

Pinout & Package

TPS2224ADB is housed in a 24-pin HTSSOP (DB) package with exposed thermal pad. Pin assignments are validated per TI SLVS428E Rev. MSRCH 2008: pins 1–2 (5V), 7 & 20 (12V, externally tied), 8 (AVPP), 9–10 (AVCC), 11 (GND), 12 (RESET), 13–14 (3.3V), 15 (OC), 17–18 (BVCC), 19 (BVPP), 21 (SHDN), 22–23 (NC), 24 (5V). Pins 3–5 (DATA/CLOCK/LATCH) form the serial control interface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS2226ADB and TPS2224APWP, the TPS2224ADB offers optimal balance of compact HTSSOP-24 packaging, proven thermal performance up to 85°C ambient, and direct compatibility with existing CardBus reference designs - making it the preferred choice for volume notebook and CableCARD™ host production.

Availability

TPS2224ADB is available at Aetrix Electronics and suitable for notebook computers, CableCARD™ host systems, and set-top box expansion modules requiring stable component supply across extended product lifecycles.

Supply support for TPS2224ADB 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 over 50 years of innovation in power management ICs.

The TPS222x family was engineered specifically for PC Card and CardBus host controllers, delivering integrated dual-slot power switching, fault reporting, and PCMCIA-compliant timing - eliminating discrete FETs, sense resistors, and sequencing logic.

FAQ

What is the maximum continuous output current supported by TPS2224ADB on its xVCC channels?

The TPS2224ADB supports 1 A steady-state output current per xVCC channel (AVCC and BVCC) at TJ = 100°C, as specified in the Electrical Characteristics table. This rating meets the PC Card Standard's peak average current requirement for 3.3-V and 5-V slots. The device uses internal current limiting and thermal shutdown to protect against sustained overloads - no external current-sense resistor is needed. TPS2224ADB maintains this rating across its full –40°C to +85°C operating ambient range with appropriate PCB thermal design.

Does TPS2224ADB support 12-V output on both AVPP and BVPP simultaneously?

Yes, TPS2224ADB supports 12-V output on both AVPP (pin 8) and BVPP (pin 19) simultaneously, as confirmed by the Terminal Functions table and Functional Block Diagram in TI SLVS428E. Both outputs share the same 12-V input rails (pins 7 and 20), which must be externally connected. This dual 12-V VPP capability distinguishes TPS2224ADB from TPS2223A (no 12-V support) and aligns with legacy PC Card flash-programming requirements. TPS2224ADB does not support 12-V on xVCC outputs - those are limited to 3.3 V and 5 V only.

How does the serial interface (CLOCK/DATA/LATCH) of TPS2224ADB function in practice?

The TPS2224ADB serial interface uses a 3-wire protocol: DATA carries 11-bit command words on CLOCK rising edges, and LATCH latches the word into control registers. Each bit corresponds to a specific switch (e.g., D0–D1 for AVCC/BVCC enable, D2–D3 for AVPP/BVPP enable). Timing requires minimum 100 ns setup/hold and 100 ns pulse width, supporting up to 2.5 MHz clock frequency. Unlike I²C or SPI, it has no address byte - all commands target the single TPS2224ADB device. This interface enables precise per-slot power control without MCU GPIO overhead.

What is the purpose of the OC (Overcurrent) pin on TPS2224ADB, and how should it be used?

The OC pin on TPS2224ADB is an open-drain output that pulls low during overcurrent (exceeding 1 A on xVCC or 100 mA on xVPP) or thermal shutdown events. It requires an external pullup resistor (typically 4.7 kΩ to 3.3 V or 5 V) to generate a valid logic-high when idle. System firmware monitors OC as an interrupt source to isolate faulty cards or initiate graceful shutdown. The 10 mA sink capability ensures robust noise immunity. OC deasserts only after fault clearance and internal recovery - no manual reset is needed. This eliminates need for external current-sense amplifiers in TPS2224ADB-based designs.

Can TPS2224ADB operate with only the 3.3-V supply applied, or are other inputs mandatory?

The 3.3-V supply (pins 13 and 14) is mandatory for all TPS2224ADB operation - it powers internal logic, control circuitry, and bias networks. However, 5-V (pins 1, 2, 24) and 12-V (pins 7, 20) supplies are only required when enabling their respective outputs: 5-V input is needed to drive AVCC/BVCC or AVPP/BVPP at 5 V; 12-V input is required only when using 12-V VPP outputs. If only 3.3-V operation is needed, 5-V and 12-V inputs may be left unconnected (though VI(5V) and VI(12V) absolute max ratings still apply). TPS2224ADB will not power up or respond to commands without valid 3.3-V supply.