AT42QT2120-SUR

AT42QT2120-SUR is Microchip’s two-key capacitive touch controller in the QT2120 family. It senses two self-capacitance touch inputs (pads on your PCB) and reports events to a host MCU over a serial interface (I2C-like). Highlights: two touch channels, on‑chip baseline tracking, programmable thresholds and debounce, wake/sleep modes for low power, and support for shield/guard to improve noise immunity. The SUR suffix indicates a specific surface-mount package variant.
Typical use: simple two-button keypads on consumer devices, appliances, remotes, or control panels where you want touch sensing with minimal MCU load.
Getting started: wire VDD/GND, connect the two touch pads to channels 0 and 1, attach shield if used, connect the serial lines to your MCU, then configure thresholds and debounce in registers (via the Microchip QT software or your firmware). See the datasheet for exact pinout and package details.

AT42QT2120-SUR is a 12-channel capacitive touch sensor controller in a SUR (surface-mount) package. Key features:
- 12 touch channels with self-capacitance (and mutual-capacitance options) sensing
- I2C-like serial interface for easy MCU integration
- Shield drive and proximity sensing for EMI/noise rejection and near-field detection
- Per-channel programmable sensitivity, touch thresholds, and baseline tracking with drift compensation
- Noise immunity and robust operation in presence of EMI or moisture
- Interrupt/status outputs for host communication
- Low-power operation with wake-on-touch and sleep modes
- On-chip oscillator; no external components required
- Wide operating voltage range with low power consumption
- Suitably packaged for compact surface-mount designs (SUR)
Note: Exact voltage range and timing details are defined in the datasheet.

- Pin count: 8 pins (AT42QT2120-SUR is an 8‑pin SUR/SOIC package).
- Function: Two‑channel capacitive touch sensor (QT2120) with I2C interface. It reads two external touch electrodes (E0, E1) and reports touch status via I2C, with VDD, GND and an optional interrupt/reset line.

Manufacturer: Microchip Technology (brand: Atmel). Microchip is a US-based semiconductor company that designs and manufactures microcontrollers, analog/mixed-signal ICs, memory, and touch-sensing solutions (the AT42QT2120-SUR comes from the Atmel/QTouch line, now under Microchip after the acquisition).

AT42QT2120-SUR is a surface-mount capacitive touch keypad controller (12-key input) for robust, low-profile user interfaces. Suitable application areas include:
- Consumer electronics: remote controls, audio/video gear, set-top boxes, keyboards
- Home appliances: microwaves, ovens, coffee makers, washing machines
- Automotive interiors: touch controls for HVAC/infotainment
- Industrial controls: sealed front-panel keypads and HMIs
- Medical devices: non-critical touch interfaces on portable equipment
- Any space-limited device needing waterproof, quiet capacitive switches

The AT42QT2120-SUR is in a 16‑pin QFN (3×3 mm) surface‑mount package with an exposed pad.