LM8300IMT9B/NOPB

Overview

The LM8300IMT9B/NOPB is a four-wire resistive touchscreen controller manufactured by Texas Instruments. It integrates a 10-bit analog-to-digital converter capable of sampling up to 500 coordinate pairs per second at a baud rate of 38400 bps via UART. The device operates within a voltage range of 2.7 V to 5.5 V and features an automatic power-saving mode with standby current typically less than 2 µA. Configuration data, including calibration points, is stored in internal non-volatile memory, eliminating the need for external EEPROM.

Feature Summary

• Integrated 10-bit A/D converter supporting up to 500 coordinate pairs per second
• Internal non-volatile storage for configuration and calibration data
• Automatic wake-up from low-power standby mode upon touch detection
• On-chip current drivers eliminate requirement for external hardware

Applications

• Personal Digital Assistants
• Smart Hand-Held Devices
• Point-of-Sales Terminals
• KIOSK Systems
• Cell Phones

Procurement Notes

Verify the package designation matches the required form factor, as the LM8300 series is available in WQFN, PLCC, and TSSOP configurations. Confirm that the specific suffix corresponds to the intended operating temperature range and packaging style. Ensure compatibility with the host system's UART interface requirements before finalizing procurement.

Selection Notes

Select this component for designs requiring a standalone four-wire resistive touch solution without external processing overhead. The internal averaging algorithms reduce noise sensitivity. Verify that the host microcontroller can handle the 38400 bps UART communication protocol and supports the necessary command byte structure for calibration and control.

Part Context

This part belongs to the LM8300/LM8500 family of touchscreen controllers. While the LM8500 supports higher clock frequencies (up to 10 MHz), the LM8300 is optimized for 3.27 MHz operation. Both devices share similar functional architectures but differ in maximum speed capabilities and specific pin functionalities related to clock selection.

Replacement Considerations

Direct replacements within the same family include the LM8500, which offers higher frequency support. Cross-family alternatives may require significant schematic and firmware modifications due to differences in interface protocols and pinouts.