Microchip Technology MTCH105-I/ST

Overview

MTCH105-I/ST from Microchip Technology is a 5-channel capacitive proximity and touch controller with active guarding, operating from 2.05V to 3.6V over –40°C to +85°C, delivering five independent open-drain digital outputs (MTO0–MTO4) for reliable touch detection in space-constrained consumer and appliance interfaces.

For engineers reviewing the MTCH105-I/ST datasheet, MTCH105-I/ST pinout, MTCH105-I/ST application, or MTCH105-I/ST equivalent, this device offers configurable sensitivity via MTSA, selectable low-power mode via MTPM, active guard support on MTI2, and noise-suppressing smart scan scheduling-key selection criteria for robust human-interface designs.

Technical Context

The MTCH105-I/ST implements a dedicated capacitive sensing engine with multi-stage active noise suppression filters and automatic environmental compensation, enabling stable operation in electrically noisy environments without host MCU intervention. It supports up to five sensor inputs (MTI0–MTI4), one of which (MTI2) doubles as an active guard output when enabled via GC control.

Sensing is configured through analog voltage on MTSA (linear sensitivity scaling from GND = max to VDD = min) and digital logic level on MTPM (VDD = fast response/high power, GND = slow response/low power). All five MTOx outputs are open-drain, requiring external pull-ups and asserting low on detection.

Key Specifications

Pinout & Package

MTCH105-I/ST is packaged in a 14-lead SOIC (Small Outline Integrated Circuit) with 1.27 mm pitch, optimized for automated assembly and thermal performance in compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar capacitive proximity and touch controller applications.

Compared with MTCH105-I/ST, MTCH102-I/SN reduces channel count and guard capability but lowers BOM cost and footprint; CY8CMBR2016 adds configurability and scalability at the expense of added firmware complexity and external component dependencies.

Availability

MTCH105-I/ST is available at Aetrix Electronics and suitable for light switch interfaces, portable device enablers, and white goods control panels requiring stable component supply, long-term industrial availability, and RoHS-compliant packaging.

Supply support for MTCH105-I/ST 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

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and interface ICs, headquartered in Chandler, Arizona, with global design and manufacturing operations certified to ISO/TS-16949.

The MTCH105-I/ST belongs to Microchip's mTouch® family of autonomous capacitive controllers, designed specifically for cost-sensitive, low-power human-interface applications where minimal host interaction and high noise immunity are critical.

FAQ

What is the function of the MTSA pin on the MTCH105-I/ST?

The MTSA pin on the MTCH105-I/ST is an analog input that sets global sensitivity across all five channels: applying GND yields maximum sensitivity, VDD yields minimum, and intermediate voltages provide linear scaling. This allows precise tuning for different overlay materials and electrode sizes without firmware changes, making MTCH105-I/ST ideal for production variants with diverse mechanical designs.

How does active guarding work on the MTCH105-I/ST?

Active guarding on the MTCH105-I/ST uses the MTI2 pin (configured as Guard via GC control) to drive a shielding waveform in-phase with the target sensor signal, minimizing voltage differential and capacitive coupling to noise sources. This significantly improves SNR in dense layouts or near noisy traces-confirmed in MTCH105-I/ST's noise suppression architecture and validated in Microchip's application notes for white goods and office equipment.

Can the MTCH105-I/ST operate from a 1.8V supply?

No, the MTCH105-I/ST has a specified minimum supply voltage of 2.05V and will not function reliably below that threshold. Operation outside the 2.05V–3.6V range may result in undefined behavior, failed detection, or brown-out lockup. For 1.8V systems, designers must use level-shifting or select alternative controllers such as Microchip's MTCH6301, not the MTCH105-I/ST.

What package type is used for the MTCH105-I/ST part number?

MTCH105-I/ST uses a 14-lead SOIC package with standard 1.27 mm lead pitch and JEDEC MS-012AC dimensions. The "ST" suffix explicitly denotes this SOIC variant, distinguishing it from the QFN-packaged MTCH105-I/QN (16-lead) and confirming compatibility with conventional reflow and wave-solder processes.

Does the MTCH105-I/ST require firmware or host processor configuration?

No, the MTCH105-I/ST operates autonomously with zero firmware dependency: all sensing, noise filtering, and output generation occur internally. Configuration is done solely via external pin states (MTPM, MTSA, GC) and passive components-no I²C, SPI, or programming interface exists. This makes MTCH105-I/ST uniquely suited for ultra-simple, cost-sensitive designs where host MCU resources are limited or unavailable.