BU21078MUV-E2

Overview

The BU21078MUV-E2 is a capacitive sensor controller IC designed for switch operation, supporting both simple and matrix configurations. It features 12 capacitive sensor ports capable of detecting up to 36 matrix switches. The device includes an integrated LED controller with PWM functionality for brightness control. Communication with the host system occurs via a 2-wire serial bus interface compatible with the I2C protocol. Key electrical specifications include a power supply voltage range of 3.0V to 5.5V, an operating temperature range of -20°C to +85°C, and a typical operating current of 3.5mA. The scan rate is typically 16msec.

Feature Summary

• Supports matrix switch arrangements with automatic self-calibration to handle external noise and temperature drift.
• Integrates an LED controller with PWM timers enabling fade-in/fade-out brightness adjustments.
• Utilizes a 2-wire serial bus interface to reduce host CPU load by sending interrupt signals upon state changes.

Applications

• Appliances requiring multiple switch inputs
• Information appliances such as printers
• AV appliances including digital TVs and HDD recorders
• Notebook PCs

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to ensure correct package type and environmental compliance. Confirm that the component meets the required RoHS standards for your target market. Cross-reference the datasheet revision number to ensure compatibility with existing design files and application notes.

Selection Notes

Select this component when a design requires handling up to 36 matrix keys or 12 simple switches within a single integrated circuit. Ensure the host microcontroller supports the required 2-wire serial communication protocol. Verify that the available GPIO pins can accommodate the necessary SCL, SDA, and INT lines for proper system integration.

Part Context

This part belongs to the BU2107x series of capacitive switch controllers from ROHM Semiconductor. It shares architectural similarities with the BU21072MUV but offers increased channel capacity. The E2 suffix typically denotes specific manufacturing or environmental compliance variations within the product line.

Replacement Considerations

BU21072MUV: Offers fewer sensor channels (10) and supports fewer matrix switches (16). BU21078FV: Provides identical functional specifications but utilizes an SSOP-B28 package instead of VQFN-28. Verify pinout compatibility before substitution.