Texas Instruments TPS2236DAP

Overview

TPS2236DAP from Texas Instruments is a dual-channel ExpressCard™ power interface switch IC designed to manage 3.3 V, 1.5 V, and AUX power rails for dual-slot ExpressCard|34/|54 host systems. It integrates current-limiting, thermal shutdown, undervoltage lockout (UVLO), and PERST/RCLKEN timing control, delivering up to 1.3 A on 3.3VOUT, 650 mA on 1.5VOUT, and 275 mA on AUXOUT - enabling compliant hot-plug power sequencing in notebook and desktop host controllers.

For engineers reviewing the TPS2236DAP datasheet, TPS2236DAP pinout, TPS2236DAP application, or TPS2236DAP equivalent, key selection criteria include dual-slot ExpressCard power rail coordination, per-rail current limiting with deglitch, PERST assertion/de-assertion timing relative to output voltage stability, RCLKEN-controlled reset sequencing, and thermal protection under sustained load conditions.

Technical Context

The TPS2236DAP implements two independent power switch channels - each with dedicated 3.3VIN→3.3VOUT, 1.5VIN→1.5VOUT, and AUXIN→AUXOUT paths - supporting simultaneous operation of two ExpressCard slots. Each channel includes integrated MOSFETs with on-resistance of 45 mΩ (3.3V), 46 mΩ (1.5V), and 120 mΩ (AUX) at TJ = 25°C, plus discharge FETs for safe rail discharge during card removal or shutdown.

Control logic enforces ExpressCard-compliant behavior: PERST is asserted when any output falls below its UVLO threshold (e.g., 3.3VOUT < 2.7 V), with 500 ns delay from fault onset and 4–20 ms de-assertion delay after all rails stabilize; RCLKEN serves as bidirectional reference clock enable with open-drain output and input capability, directly gating PERST timing via host coordination.

Key Specifications

Pinout & Package

The TPS2236DAP is housed in a 32-pin PowerPAD™ HTSSOP package with exposed thermal pad, optimized for dual-slot ExpressCard host designs requiring high thermal efficiency and board-level EMI control.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS2231 variants, the TPS2236DAP provides true dual-slot independence - including separate SHDN/STBY/PERST/RCLKEN/OC per slot - enabling fault containment and asynchronous power management essential for multi-card host systems.

Availability

TPS2236DAP is available at Aetrix Electronics and suitable for notebook computers, desktop computers, personal digital assistants (PDAs), and digital cameras requiring stable component supply for ExpressCard expansion interfaces.

Supply support for TPS2236DAP 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 for industrial, automotive, and computing markets.

The TPS2236DAP belongs to TI's ExpressCard power interface product line, engineered specifically to meet the stringent voltage sequencing, timing, and safety requirements defined in the ExpressCard standard for dual-slot host systems.

FAQ

What is the primary function of the TPS2236DAP in an ExpressCard host system?

The TPS2236DAP serves as a dual-channel power interface switch that manages independent 3.3 V, 1.5 V, and AUX power delivery to two ExpressCard slots. It enforces ExpressCard-compliant sequencing, provides per-rail current limiting and thermal protection, and generates coordinated PERST and RCLKEN signals - all within a single 32-pin PowerPAD HTSSOP package. The TPS2236DAP ensures safe hot-plug operation and fault isolation between slots.

How does the TPS2236DAP handle overcurrent events on its output rails?

The TPS2236DAP monitors each output rail (3.3VOUT1/2, 1.5VOUT1/2, AUXOUT1/2) with dedicated current-sense circuitry. Upon detecting an overcurrent condition, it asserts the corresponding OC1 or OC2 open-drain output after a 6–20 ms deglitch period to prevent false triggering. The affected rail remains disabled until the fault clears and the device resets - ensuring system-level reliability without latch-up. The TPS2236DAP does not auto-retry.

What is the role of RCLKEN in the TPS2236DAP, and how does it interact with PERST?

RCLKEN in the TPS2236DAP is a bidirectional pin serving as both an output (power-good indicator) and input (reset gate). As an output, it transitions high only after all three output rails stabilize within tolerance; this rising edge starts an internal timer that triggers PERST de-assertion after 4–20 ms. As an input, holding RCLKEN low externally delays PERST de-assertion - allowing host coordination with clock domain readiness. The TPS2236DAP relies on this interaction to meet ExpressCard timing compliance.

Does the TPS2236DAP support independent control of each ExpressCard slot?

Yes, the TPS2236DAP provides fully independent control per slot: SHDN1/SHDN2, STBY1/STBY2, CPPE1/CPPE2, CPUSB1/CPUSB2, PERST1/PERST2, RCLKEN1/RCLKEN2, and OC1/OC2 are electrically isolated signal pairs. This allows asymmetric power states - e.g., Slot 1 active while Slot 2 is in standby - and prevents fault propagation between slots. The TPS2236DAP is explicitly designed for such dual-slot autonomy.

What thermal performance can be expected from the TPS2236DAP in a typical host design?

In a JEDEC low-k board with the PowerPAD soldered to a thermal plane, the TPS2236DAP delivers 993.4 mW continuous power dissipation at TA = 25°C, derating to 366 mW at TA = 85°C. Its thermal shutdown activates at 155–165°C junction temperature with 10°C hysteresis. For sustained dual-rail operation (e.g., 1.3 A on both 3.3VOUTs), proper PCB copper area under the PowerPAD is essential - the TPS2236DAP's thermal design assumes direct pad-to-plane connection.