Intersil’s ISL45041 is a 7-bit, non-volatile programmable Vcom calibrator with I2C interface for setting backplane common voltage in thin film transistor liquid crystal displays (TFT-LCDs). The device is designed to reduce the flicker of an LCD panel by adjusting the Vcom voltage during production, effectively replacing the mechanical potentiometers normally needed to adjust Vcom. The ISL45041 incorporates an I2C interface and a 128-step adjustable sink current output current control. Its digital interface controls the sink-current output that attaches to an external voltage driver to establish the required Vcom voltage setting. Adjusting the Vcom of TFT-LCD panels is a labour-intensive process that can be simplified by using the ISL45041 non-volatile Vcom calibrator.

The device also includes an EEPROM bank. The device lets set and drive the desired Vcom voltage on the TFT-LCD panel via the I2C interface and with a resolution of 7 bits. Once the ideal value is found, it can be programmed and stored in the on-board non-volatile EEPROM memory bank. Then, after it is set, the Vcom voltage can be driven throughout the common backplane via a rail-to-rail input and output, high-output-current Vcom driver. Key features of the ISL45041 include an analogue voltage range of 4.5V to 18V, a digital voltage range from 2.25V to 3.6V, an output adjustment SET pin, and an output that is guaranteed to be monotonic over temperature. Target applications for the device include TFT-LCD screens for televisions, notebook computers, and monitors. The device is available now in a DFN-8 lead-free package measuring 3mm x 3mm, with a maximum thickness of 0.8mm.