| MICROCHIP TECHNOLOGY INCORPORATED Patent applications |
| Patent application number | Title | Published |
|---|
| 20110093639 | Secure Communications Between and Verification of Authorized CAN Devices - Encrypted encoding and decoding of identification data of CAN bus devices for communications therebetween provides deterrence of theft and unauthorized access of these secure CAN bus devices. Each one of the CAN bus devices is considered a “node” on the CAN bus for communications purposes. By using a unique encryption code stored in each of the “authorized” CAN bus devices, unauthorized CAN bus nodes will not be able to communicate with the authorized, e.g., secure, CAN bus nodes functioning in a CAN system. | 04-21-2011 |
| 20100148678 | LED Brightness Control by Variable Frequency Modulation - Perceived intensity (brightness) of light from a light emitting diode (LED) is controlled with a pulse train signal having fixed pulse width and voltage amplitude and then increasing or decreasing the frequency (increasing or decreasing the number of pulses over a time period) of this pulse train signal so as to vary the average current through the LED. This reduces the level of electro-magnetic interference (EMI) at any one frequency by varying the pulse train energy spectrum over a plurality of frequencies. | 06-17-2010 |
| 20100103013 | Method and Apparatus for Dithering in Multi-Bit Sigma-Delta Digital-to-Analog Converters - A multi-bit (M-bit, M>1) Sigma-Delta digital-to-analog converter (DAC) with a variable resolution multi-bit quantizer that has its digital value inputs that are truncated or rounded to a resolution that follows a random or pseudo-random sequence to provide automatic dynamic dithering for removing undesired idle tones in the analog output of the Sigma-Delta DAC. Random numbers N(n) between 1 and M are provided, and M−N(n) least significant bits in each M-bit digital value at the output of the quantizer are forced to zero with a digital truncator or rounder. The random numbers N(n) may be provided by a random or pseudo-random sequence generator, e.g., Galois linear feedback shift register in combination with digital comparators and an adder. | 04-29-2010 |
| 20100103005 | Self Auto-Calibration of Analog Circuits in a Mixed Signal Integrated Circuit Device - Auto-calibration of the analog circuits occurs when requested by a user and/or the occurrence of an event(s). The user may invoke an auto-calibration on demand through an auto-calibration (A | 04-29-2010 |
| 20100102851 | P-Type Source Bias Virtual Ground Restoration Apparatus - A virtual ground restoration circuit is used to substantially eliminate excessive current from occurring in an integrated circuit device having two or more logic circuit modules in different voltage domains. Excessive current is caused when a signal between the two or more logic circuit modules in different voltage domains is at logic “0” and one of the logic circuit modules is biased at a voltage level above the true ground or common power source voltage, V | 04-29-2010 |
| 20100102832 | Automated Capacitive Touch Scan - A scan module of an electronic device scans a capacitive keypad for detection of the actuation of any capacitive touch sensor. This scan module remains in operation even when major power consuming circuits of the electronic device are in a sleep mode, and will not wake up the major power consuming circuits until an action requiring the circuits is needed, thereby, reducing overall power consumption of the electronic device while still maintaining scanning of the capacitive keypad. Upon detection of a valid key press of a capacitive touch sensor, an interrupt to the electronic device brings it out of a sleep mode and into an operating mode for further processing and appropriate action commensurate with the actuation of the specific capacitive touch sensor. | 04-29-2010 |
| 20100102830 | Physical Force Capacitive Touch Sensor - A physical force capacitive touch sensor comprises a capacitive sensor element on a substrate, a physically deformable electrically insulating spacer over the capacitive sensor element, and a conductive plane over the physically deformable electrically insulating spacer that is substantially parallel to the capacitive sensor element. The conductive plane is connected to a power supply common and/or grounded to form a capacitor with the capacitive sensor element and for improved shielding of the capacitive sensor element from electrostatic disturbances and false triggering thereof. A protective cover may be placed over the conductive plane to act as an environmental seal for improved physical and weather protection, but is not essential to operation of the capacitive touch sensor. | 04-29-2010 |
| 20100079078 | Using Pulse Density Modulation for Controlling Dimmable Electronic Lighting Ballasts - Pulse Density Modulation (PDM) controls light brightness from a fluorescent lamp by applying voltages to the lamp filaments at two or more sequential signal frequencies. A low frequency, an intermediate frequency and a high frequency may be used to control the brightness of the lamp. The lamp gas ionizes to produce light only when the low or intermediate frequency voltage is applied thereto. The lamp gas is not ionized at the high frequency voltage, but the high frequency voltage keeps the lamp filaments warm during low brightness conditions. The low frequency, intermediate frequency, no and/or high frequency voltages have time periods that occur within a modulation frame time period that repeats continuously. The ratio of the low frequency and intermediate frequency time periods, and the no and/or high frequency voltage time periods determine the light output of the fluorescent lamp, and also maintain a proper temperature of the filaments. | 04-01-2010 |
| 20100017490 | Serial Communications Device with Dynamic Allocation of Acceptance Masks Using Serial Implementation - A CAN module or a microcontroller comprises a CAN module which receives a serial bit stream. The CAN module comprises a filter register with a bit select input and a single bit output, a bit select unit for selecting a bit of the filter register in accordance with the serial bit stream, a comparator coupled with the single bit output and with the serial bit stream for generating a comparison signal, and a register receiving the comparison signal for accumulating a plurality of comparison results and for generating an acceptance signal. | 01-21-2010 |
| 20090316847 | Automatic Synchronization of an Internal Oscillator to an External Frequency Reference - An internal integrated circuit clock oscillator is automatically synchronized to an external frequency reference by counting the number of periods of the internal clock oscillator (hereinafter “count”) that occur within a period of a lower frequency external frequency reference then comparing the count to the reference count. When the reference count is greater than the count, the frequency of the internal clock oscillator is increased. When the reference count is less than the count, the frequency of the internal clock oscillator is decreased. When the reference count and the count are substantially the same, the frequency of the internal clock oscillator is not changed. | 12-24-2009 |
| 20090256674 | Programmable Selective Wake-Up for Radio Frequency Transponder - A remote keyless entry (RKE) transponder has a programmable selective wake-up filter for determining whether the RKE transponder should wake-up to process a received signal. The wake-up filter correlates the timing of an input signal's carrier amplitude on and off time periods to a predefined programmable time period profile for a desired signal which has a certain carrier on time (time period on) and a certain carrier off time (time period off) arranged into a coded “header.” When a received signal matches the predefined time period profile, then the RKE transponder will wake-up to process the incoming signal data. The predefined time period profile may be programmable and may be stored in a header configuration register. Each RKE transponder has unique predefined time period on and time period off profiles. | 10-15-2009 |
| 20080272830 | Variable Power and Response Time Brown-Out-Reset Circuit - A brown-out-reset circuit having programmable power and response time characteristics. These characteristics may be programmed over an n-bit wide bus for 2 | 11-06-2008 |
