ATMXT112S-MAU - 112-Node maXTouch Touch Controller | Microchip
MPN: ATMXT112S-MAU β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
ATMXT112S-MAU Overview
A capacitive touch controller is a specialized interface IC that drives and measures a self-capacitance or mutual-capacitance touch sensor matrix, converting raw capacitance changes from finger or stylus contact into processed touch coordinates delivered to a host processor. Within the system hierarchy, it sits between the passive touch sensor (ITO pattern on glass or film) and the application host MCU, making it a core element of human-machine interface (HMI) subsystems in embedded electronics.
Key features of the ATMXT112S-MAU include the maXTouch S Series architecture with 112 touch nodes supporting screens up to 3.5 inches, mutual-capacitance sensing for true multi-touch performance, and integrated touch processing that offloads touch detection, noise filtering, and coordinate calculation from the host processor. The maXTouch family is widely deployed in consumer, industrial, and appliance HMIs where reliable gloved-touch and water-rejection behavior is valued.
Technically, the S Series integrates an acquisition engine that drives transmit lines and measures receive nodes through charge-integration front ends, followed by on-chip digital signal processing for touch classification. Configuration and calibration parameters are stored on-chip, and communication with the host is handled over a standard serial interface, per the manufacturer datasheet.
Typical applications include small-format touchscreen HMI panels for appliances, wearable and handheld devices, automotive-style control panels, and industrial operator interfaces where a compact 3.5-inch or smaller capacitive touchscreen is used.
Design consideration: note that Microchip has marked the ATMXT112S product page with a recommended alternative touch controller, ATMXT144U, so new designs should verify end-of-life status and consider the recommended successor before committing to new layouts.
This page synthesizes distributor stock signals, the manufacturer's recommended-alternative notice, drop-in replacement guidance, and practical design notes not found in the datasheet alone.
Drop-in alternatives for ATMXT112S-MAU β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATMXT112S-MAU (same form factor and footprint).
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMXT144U
β Drop-Inπ Reference alternative (not in catalog)
ATMXT112S-MCU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMXT112S-MAU Maximum Ratings & Electrical Characteristics
| Product Type | Capacitive Touchscreen Controller |
| Family | maXTouch S Series (mXT112S) |
| Touch Channels / Nodes | 112 |
| Max Screen Size | 3.5 inch |
| Sensing Technology | Projected capacitive (mutual capacitance) |
| Package | 32-UQFN (4x4 mm) |
| Mounting Type | Surface Mount |
ATMXT112S-MAU 32-uqfn (4x4 mm) Pin Configuration Guide
Pin configuration for ATMXT112S-MAU (32-uqfn (4x4 mm) package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for ATMXT112S-MAU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMXT112S-MAU is suitable for 6 applications: Small Appliance Touch HMIs, Handheld and Wearable Devices, Industrial Operator Interfaces, Automotive-Style Control Panels, Smart Home and IoT Panels, POS and Payment Terminals.
Small Appliance Touch HMIs
The ATMXT112S-MAU fits appliance control panels where a capacitive touchscreen up to 3.5 inches provides the primary user interface, such as coffee machines, ovens, and smart thermostats. Its 112-node mutual-capacitance S Series architecture delivers accurate multi-touch detection across a compact sensor, while on-chip processing performs touch classification, noise filtering, and coordinate calculation so a low-cost host MCU can be used. Placed directly behind the ITO sensor with a serial link to the host, the controller removes touch burden from the main firmware. Because the part is end-of-life, new appliance platforms should design with the Microchip-recommended ATMXT144U while using the mXT112S only for service and sustainment builds.
Recommended
Handheld and Wearable Devices
Handheld instruments, medical portables, and rugged wearable terminals commonly use 2.4-to-3.5-inch touchscreens, matching the ATMXT112S-MAU's stated maximum panel size exactly. The 32-UQFN 4x4 mm package conserves board area in space-constrained portable designs, and the S Series acquisition engine maintains touch accuracy through the noise environments typical of battery-powered devices. The controller streams processed touch coordinates over its serial host interface, minimizing host firmware complexity. Wet-hand and glove tolerance behavior defined in the maXTouch configuration allows customization for field conditions. Designers of new portable platforms should note the device's end-of-life status and evaluate the ATMXT144U to secure long-term supply while preserving the same touch-user experience.
Recommended
Industrial Operator Interfaces
Compact industrial HMI panels - machine status displays, configuration terminals, and small SCADA local interfaces - frequently use sub-3.5-inch capacitive touchscreens where the ATMXT112S-MAU's 112 sensing nodes provide the required resolution. On-chip DSP filtering helps reject interference from nearby switching supplies and motor drives common in industrial cabinets, and the configuration object architecture lets engineers tune sensitivity for gloved operation. The QFN package's exposed pad supports robust grounding for EMI-heavy environments. Since the maXTouch family processes touches autonomously, the industrial host controller only receives finalized coordinates, simplifying software certification. For new industrial designs, migrate to the ATMXT144U per Microchip's recommendation; sustain existing panels with remaining mXT112S stock.
Recommended
Automotive-Style Control Panels
Center-console style capacitive touch controls and aftermarket automotive HMI modules often use small touchscreens within the 3.5-inch class targeted by the mXT112S. The S Series architecture's fast scanning and noise immunity support use near displays, backlight inverters, and vehicle electrical noise sources when the configuration is tuned appropriately. The controller's autonomous touch processing frees the body-control host from real-time touch scanning. Note that the standard ATMXT112S-MAU is not asserted as AEC-Q100 qualified in the reviewed data, so verification of automotive qualification requirements is mandatory before use in production vehicle programs; the maXTouch family's automotive-qualified variants should be evaluated instead where required.
Recommended
Smart Home and IoT Panels
Smart thermostats, door-station displays, and wall-mounted IoT control panels typically integrate 2.8-to-3.5-inch touchscreens, squarely within the ATMXT112S-MAU's supported range. The 112-node sensor supports gesture-class multi-touch interactions used in modern thermostat UIs, while on-chip calibration and self-test routines maintain reliability over long unattended service lives. The compact 32-UQFN package suits the dense, low-profile PCBs used in wall plates. Host processors receive processed coordinates over a simple serial interface, keeping IoT firmware lean. Because the part is end-of-life, IoT platform developers should standardize on the Microchip-recommended ATMXT144U for new product introductions and treat mXT112S stock as bridging inventory for existing SKUs.
Recommended
POS and Payment Terminals
Point-of-sale handhelds and compact payment terminals use small capacitive touchscreens, typically 3.5 inches or smaller, matching the mXT112S design point. Touch reliability is revenue-critical in these devices, and the S Series controller's on-chip processing provides stable, jitter-free coordinate reporting that supports signature capture and PIN-entry UX. The controller's configurable sensitivity settings accommodate fingerprint-worn panels and protective overlays used in commercial environments. Integration consists of connecting the sensor matrix, decoupling supplies, and loading the maXTouch configuration over the host interface. New terminal platforms should adopt the ATMXT144U per Microchip's product page guidance, while service organizations can sustain installed fleets with remaining ATMXT112S-MAU stock.
Recommended
Recommended Products Summary
Engineering reference data for ATMXT112S-MAU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMXT144U |
|---|---|---|
| Brand | Microchip Technology (Atmel) | Microchip Technology |
| Lifecycle Status | EOL (successor recommended) | Active (recommended replacement) |
Key Differentiators
- Manufacturer-endorsed migration path (vs ATMXT144U)
- S Series autonomous touch processing (vs ATMXT144U)
- Compact 32-UQFN 4x4 mm footprint (vs ATMXT144U)
Design Notes
The most critical design pitfall with the ATMXT112S-MAU is its end-of-life status: Microchip's official product page explicitly names the ATMXT144U as the recommended alternative touch controller. Any new PCB layout using the mXT112S carries supply risk. Before committing production, verify remaining distributor stock (Mouser, DigiKey list the part) and qualify the ATMXT144U footprint in parallel, even if the first builds use mXT112S stock.
maXTouch controllers are sensitive to switching-noise coupling into the sensor matrix. Keep the touch controller and its sensor traces away from switching regulators, backlight drivers, and high-current traces; use a solid ground plane beneath the sensor routing and connect the QFN exposed pad solidly to ground with an array of vias. Follow the sensor layout guidance in the manufacturer's maXTouch design application notes for trace pitch and shield (guard) ring usage around the sense lines.
Provide clean, well-decoupled power to the touch controller: place ceramic decoupling capacitors at each supply pin of the 32-UQFN as close as possible to the pads, and if the touch IC shares a rail with a display backlight or radio, add an RC or ferrite-bead filter for the touch supply. Noise on the analog supply directly degrades signal-to-noise ratio of the capacitance measurement, which appears as jittery or missed touches. Exact supply voltage and current figures should be taken from the official datasheet.
Compliance Information
Compliance data not present in reviewed distributor snippets as of 2026-09-19; confirm on the official Microchip product page or request a compliance certificate.
