Broadcom Corporation

Xin Dai

David A Sobel

Sumant Ranganathan

Fang Lin

An apparatus that is configurable to perform a forward scan, a row scan, and a column scan is disclosed. The apparatus includes a path selection module coupled to a transmitter and a receiver. The path selection module includes a row-transmit switch, a column-receive switch, a row-receive switch, and a column-transmit switch that are configurable to form various transmit paths and receive paths to perform the forward scan, a row scan, and a column scan. The row-transmit switch and the column-transmit switch cascades switching transistors to protect against large voltage swings present in an output of the transmitter, controls the gate voltage that is applied to these switching transistors to protect against the large voltage swings, and includes additional protection circuitry to ensure their reliability. The column-receive switch and the row-receive switch uses thick oxide transistors to protect thin oxide transistors against the large voltage swings and/or includes additional protection circuitry to ensure their reliability.

Transmit/receive switch for a touch-screen system

A mode-configurable amplifier comprises a single-ended input for receiving a received signal from a capacitive touch panel, a differential output operable to carry a differential processed signal to a subsequent processing stage, and processing circuitry in communication with the single ended input and the differential output. The processing circuitry comprises mode selection inputs and mode selection circuitry in communication with the mode selection inputs. The mode selection circuitry is operable to configure the processing circuitry into a current operating mode selected from a high-pass filter mode, bandpass filter mode, and a trans-capacitive gain mode. The high-pass filter mode is operable to high-pass filter the received signal to obtain the differential processed signal. The bandpass filter mode is operable to bandpass filter the received signal to obtain the differential processed signal. The wideband gain mode is operable to amplify the received signal to obtain the differential processed signal.

Growing community of inventors

Fremont, CA, United States of America

Xin Dai