STMicroelectronics STMPE2401TBR

Overview

STMPE2401TBR from STMicroelectronics is a 24-bit I²C GPIO port expander with integrated keypad controller (8×12 matrix), three 8-bit PWM channels for LED brightness control, interrupt output, and hotkey wake-up per GPIO - operating at 1.8 V supply voltage in TFBGA36 package. It serves as a system-level peripheral interface IC in mobile multimedia platforms to extend host ASIC GPIO resources while enabling keypad scanning, backlight dimming, and rotator decoding.

For engineers reviewing the STMPE2401TBR datasheet, STMPE2401TBR pinout, STMPE2401TBR application, or STMPE2401TBR equivalent, this device supports low-power embedded human-interface subsystems requiring configurable I/O, hardware-accelerated key scanning, and synchronized PWM timing without host CPU overhead.

Technical Context

The STMPE2401TBR implements a hierarchical register-mapped architecture with independent clock-gated modules: Keypad Controller (KPC) scans rows/columns autonomously using internal state machine logic; PWM controller executes preloaded 8-bit duty-cycle instructions on three dedicated outputs; GPIO module supports input/output/alternate-function configuration per pin with Schmitt-trigger inputs and programmable pull-up/down.

Its I²C interface complies with Philips I²C Specification v2.1, supporting Standard (100 kbps) and Fast (400 kbps) modes with 7-bit slave addressing (four possible addresses via ADDR0/ADDR1 pins), auto-incrementing register access across most modules, and General Call support - enabling multi-device bus coordination in space-constrained portable designs.

Key Specifications

Pinout & Package

STMPE2401TBR is housed in a 3.6 mm × 3.6 mm TFBGA-36 package with 0.5 mm pitch and bottom-side ball layout. The package supports high-density PCB routing and thermal dissipation suitable for handheld consumer electronics.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar GPIO expansion and keypad interface applications.

Compared with TCA6424AIPWR and PCA9555DWR, the STMPE2401TBR uniquely integrates keypad scanning, three PWM channels, and rotator decoding - delivering complete human-interface subsystem functionality in a single 1.8 V device, reducing BOM count and firmware complexity for portable electronics.

Availability

STMPE2401TBR is available at Aetrix Electronics and suitable for smartphone keypad interfaces, portable media player backlight control, game console rotary encoder systems, and industrial handheld terminal GPIO expansion requiring stable component supply and long-term lifecycle support.

Supply support for STMPE2401TBR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, analog ICs, MEMS, and power management solutions for automotive, industrial, and consumer markets.

The STMPE series targets portable and battery-powered human-interface subsystems, combining GPIO expansion with application-specific accelerators like keypad controllers, PWM engines, and rotator decoders to minimize host processor load and power consumption.

FAQ

What is the maximum keypad matrix size supported by the STMPE2401TBR?

The STMPE2401TBR supports up to an 8×12 keypad matrix, using eight KP_X pins as column inputs and twelve KP_Y pins as row outputs. This configuration enables scanning of 96 keys with hardware acceleration, including automatic debouncing, FIFO buffering, and interrupt-on-press/release - all without host CPU intervention.

Does the STMPE2401TBR require an external crystal for operation?

No - the STMPE2401TBR includes an internal 32 kHz RC oscillator for keypad, PWM, and rotator timing. An external 32 kHz crystal can be connected between XTALIN and XTALOUT pins to improve timing accuracy, but it is optional. The internal oscillator remains functional and sufficient for most portable applications.

How does the hotkey wake-up feature operate in low-power modes?

In Sleep or Hibernate mode, any enabled GPIO can generate a wake-up event on rising/falling edge. The hotkey function configures individual pins to assert the open-drain INT pin and restore clocking to the relevant module - allowing immediate key detection while maintaining ≤50 µA or ≤12 µA quiescent current respectively.

Can the STMPE2401TBR's PWM outputs drive LEDs directly?

Yes - the three PWM outputs (PWM1–PWM3) are CMOS-compatible GPIOs capable of sinking up to 4 mA per pin. They can directly drive low-current indicator LEDs or interface with external MOSFETs/transistors for higher-power backlight segments, provided external current-limiting resistors are used per LED string.