STMPE821QTR

Touch Capacitive Sensor Overview

The STMPE821QTR is an obsolete S-Touch 8-channel capacitive touchkey controller manufactured by STMicroelectronics. It integrates up to 8 configurable GPIOs and capacitive touch key inputs within a QFN16 package (2.6 x 1.8 mm). The device operates on a supply voltage of 2.7 V to 3.6 V, featuring an internal regulator for core operation. Communication is handled via an I2C interface supporting standard and fast modes with 7-bit and 10-bit addressing. Key electrical specifications include 8 kV HBM ESD protection, 50 fF capacitance measurement resolution across 128 steps, and a sleep mode current consumption of 25 μA.

Touch Capacitive Sensor Feature Summary

• Configurable 8-channel architecture allowing flexible assignment between general-purpose I/O and capacitive touch sensing
• Integrated environment tracking calibration and advanced data filtering to maintain sensitivity under varying conditions
• Low-power management capabilities including sleep mode with continuous touch detection capability
• Built-in basic PWM controller for driving external loads such as LEDs or buzzers

Touch Capacitive Sensor Applications

• Mobile phones and smartphones
• Portable media players
• Game consoles

Touch Capacitive Sensor Procurement Notes

This component is officially listed as obsolete by the manufacturer. Verification of availability requires checking secondary market distributors or surplus suppliers. Designers should confirm lead times and authenticity carefully, as original stock may be limited. Replacement strategies should be evaluated immediately to ensure long-term supply chain stability.

Touch Capacitive Sensor Selection Notes

Select this part only if the specific 8-channel capacitive touch requirement matches the legacy design constraints. Verify that the QFN16 footprint and 2.7-3.6 V operating range align with the system power budget. Consider the I2C address configuration and interrupt pin requirements during schematic capture to ensure compatibility with the host microcontroller.

Touch Capacitive Sensor Part Context

The STMPE821 belongs to the STMPE series of peripheral controllers from STMicroelectronics. It is specifically designed for capacitive touch interfaces in portable electronics. The 'QTR' suffix indicates the tape and reel packaging format suitable for automated surface-mount assembly processes.

Touch Capacitive Sensor Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation due to the product's obsolete status. Engineers must consult official STMicroelectronics replacement guides or contact technical support for qualified alternatives.