Motorola Corporation

Cts Corporation

Sang Hoon Kim

Robert S Witte

Glen O Reeser

Kevin L Haas

Edward E Li

Brian D Chapman

Lunal Khuon

Ralph M Mitchell

Beverly A Carroll

Weiping Zhang

Andrew V Schultz

Harold Papazian

Edward Bruzgo

A power supply system (300) provides a staged startup of multiple loads (303, 305). Preferably, the power supply (300) is a switching power supply that provides power, in the form of a primary output voltage to a first output terminal (319) and to a second output terminal (325). A first load (303) demands a first startup power from the switching power supply through the first output terminal (319). A voltage comparator (333) provides an enable signal (335) when a primary output signal, present at the first output terminal, exceeds a predetermined threshold (335). A load coupling device, preferably a gateable voltage regulator (331), is coupled to the second output terminal (325). The gateable voltage regulator (331) has an output (327) coupled to a second load (305). The gateable voltage regulator (331), responsive to the enable signal (335), provides a coupling between the second output terminal (325) and the second load (305), whereby the second load (305) demands a second startup power from the power supply through the second output terminal (325).

Power supply distributed load startup system

A method (100) for mechanically tuning a VCO that has a resonant stripline having vias in predetermined locations connected through a circuit board to ground. This includes a step (104) of measuring the operating frequency of the VCO. A following step (106) includes calculating an amount of frequency shift needed to achieve a desired frequency. A following step (108) matches the amount of frequency shift needed to values in a look-up table of frequency shifts versus via locations to determine which vias locations will provide the proper amount of frequency shift. A last step (110) includes mechanically disconnecting from ground the via locations indicated in the third step such that the desired frequency is achieved. This method (100) of tuning allows VCO frequency adjustment after final assembly avoiding problems of frequency shifts that can occur due to the placement of a metal lid on the circuit board after assembly.

Method for mechanically tuning a voltage controlled oscillator

A piezoelectric resonator (10) with electrodes (14) having a periodic pattern (28) along a portion of an edge (30) of at least one of the electrodes (26). The periodic pattern (28) has a periodicity that destructively interferes with the undesirable vibrational mode. For example, a rectangular AT-cut quartz resonator, which vibrates in a thickness-shear mode may also possess undesirable flexure and face-shear modes. These modes not only present undesirable spurious frequencies, they also change over temperature, disturbing a frequency-temperature response (16) of the quartz crystal. The periodic pattern (28) substantially reduces these undesirable modes, providing a more uniform frequency-temperature response which is beneficial in temperature compensated crystal oscillator applications.

Electrode edge wave patterns for piezoelectric resonator

A method (202) for etching photolithographically produced quartz crystal blanks for singulation. In a first step (202), a quartz wafer is plated on both sides with metal and subsequently coated on both sides with photoresist. In a second step (204), the photoresist is patterned and developed and the metal layer on one side is etched through to form a narrow channel in the quartz defining a perimeter of a quartz blank. In a third step (206), the quartz channel is preferentially etched partially into the wafer along parallel atomic planes to provide a mechanically weak junction between the quartz wafer and the blanks to be singulated. In a fourth step (208), the photoresist layers are stripped from the quartz wafer. In a final step (210), the quartz blank is cleaved substantially along the bottom of the quartz channel to singulate the crystal blanks from the quartz wafer.

Method for etching photolithographically produced quartz crystal blanks

A method and system (400) for controlling battery charging including applying a predetermined voltage to a battery (500) to be charged, increasing the voltage applied to the battery (500) to a known maximum battery charging voltage, measuring a current supplied to the battery (500) at the maximum battery charging voltage, supplying a predetermined set of constant current charging levels, and setting a charging current level equal to one of the set of predetermined constant current charging levels based on the current supplied to the battery at the maximum battery charging voltage for minimizing an amount of time needed to charge the battery (500) and maximizing a useful life of the battery (500).

Method and system for battery charging

An electric motor control with integral battery charger includes battery terminals (201) for connection to a battery (203). A boost converter circuit (111) is coupled to an armature winding (209) of the electric motor (117), and has an input (131) coupled to a power source (211). A buck converter circuit (105) is coupled to a field winding (207) of the electric motor (117), and an input (133) coupled to the power source (211). A controller (205), is coupled to the battery terminals (201) and the power source (211). The controller (205) couples a boost output (107) of the boost converter circuit (111 ) to the battery terminals (201) while a terminal voltage of the power source (211) is lower than a terminal voltage of the battery (203) measured at the battery terminals (201), and couples a buck output (107) of the buck converter circuit (105) to the battery terminals (201 ) while the terminal voltage of the power source (211) is higher than the terminal voltage of the battery (203).

Growing community of inventors

Hoffman Estates, IL, United States of America

Sang Hoon Kim