Abstract: A power converter includes a primary winding for providing a primary current, a secondary winding for providing an output current and an output voltage, and a current sense node for receiving a current sense signal related to the primary current. The power converter also includes a control circuit configured to limit the current sense signal to be lower than or equal to a predetermined reference peak current. Moreover, the power converter includes a first circuit configured to modify the current sense signal using a first signal related to the output voltage to cause an variation in the output current.

Abstract: An electrical plug, for example an AC adaptor, has a pair of pins that may be moved between an operative position and a non-operative position in which the pins are received within slots formed in a body. When in the non-operative position the pins are completely received within the slots and a mechanism is provided for releasing the pins from the slots when it is desired to move the pins into their operative position. The pins pivot about a pivot axis located adjacent an edge of the body so that the pins pivot outwardly towards the edge into their operative position.

Abstract: An automated self-service mail processing and storing system is disclosed which is capable of receiving input from and providing instructions to a user via a touch-sensitive screen or a digitized voice system. The system is capable of weighing the mail item, receiving user identification information from a credit/debit card, for example, for payment, calculating the charge for shipment and deducting that amount from the user's charge account, and securely storing the item for subsequent pickup. The system contains a novel weighing means capable of detecting minute vibrations for purposes of obtaining an accurate weight amount. The system may also contain a tracking bar code generation means and a tracking bar code verification system. Optionally, a dual floppy disk system allows the user to send electronic mail, and a built-in facsimile apparatus allows the user to send “FAX” information through the telephone line.

Abstract: An in-rush current controller for a mains power rectification circuit including a fill wave rectifier and a capacitor. A serial resistor suppresses in-rush currents. The controller includes a sensing circuit that controls a pair of silicon controlled rectifiers to cyclically shunt or isolate the resistor during normal operation. Thus, power is not dissipated by the resistor and undesirable heat is not generated during normal operation. The sensing circuit responds to abrupt rises in voltage (typical of in-rush current conditions) to inhibit turn ON of the rectifiers so that the resistor is not shunted or isolated at such times.

Abstract: A voltage clamp for a single-ended flyback converter provides partial leakage energy recovery and noise suppression. The voltage clamp is an improved version of a conventional RCD clamp. The voltage clamp includes two switches with different turn-off speeds. The voltage clamp includes a capacitor and two resistors. One resistor is connected in parallel with a capacitor and the other resistor is connected in parallel with the faster switch. The faster switch enables at least partial recovery of energy dissipated in a clamp resistor immediately after turn OFF of the slower switch. When the slower switch opens after the faster switch closes, noise in the circuit is suppressed by a damping resistor which remains effectively in a current path after the faster switch has re-opened.

Abstract: A DC-to-DC converter is described that provides resonant-transition switching by ensuring that the voltage across a first switch falls to zero between cycles.

Abstract: A voltage clamp for a single-ended flyback converter provides partial leakage energy recovery and noise suppression. The voltage clamp is an improved version of a conventional RCD clamp. The voltage clamp includes two switches with different turn-off speeds. The voltage clamp includes a capacitor and two resistors. One resistor is connected in parallel with a capacitor and the other resistor is connected in parallel with the faster switch. The faster switch enables at least partial recovery of energy dissipated in a clamp resistor immediately after turn OFF of the slower switch. When the main switch opens after the faster switch closes, noise in the circuit is suppressed by a damping resistor which thereby remains effectively in a current path after the faster switch has re-opened.

Abstract: An automated self-service mail processing and storing system is disclosed which is capable of receiving input from and providing instructions to a user via a touch-sensitive screen or a digitized voice system. The system is capable of weighing the mail item, receiving user identification information from a credit/debit card, for example, for payment, calculating the charge for shipment and deducting that amount from the user's charge account, and securely storing the item for subsequent pickup. The system contains a novel weighing means capable of detecting minute vibrations for purposes of obtaining an accurate weight amount. The system may also contain a tracking bar code generation means and a tracking bar code verification system. Optionally, a dual floppy disk system allows the user to send electronic mail, and a built-in facsimile apparatus allows the user to send "FAX" information through the telephone line.

Abstract: A power circuit for a fluorescent discharge lamp comprising a converter for producing a DC output. A voltage controlled oscillator is driven by the output from the converter, the oscillator providing a high voltage output for driving the lamp. The frequency of the output increases and decreases with increases and decreases in the powering voltage from the converter. A current detector detects the current passing through the lamp and controls the output voltage of the converter according to that current to increase the the voltage to strike the lamp and then control the voltage to give the required running current.

Abstract: An apparatus capable of automatically handling envelopes through various stages of processing, including electronic display of the envelope, electronic weighing of the envelope and printing of a stamp, date, time, location and ZIP+4 code in numerical and bar code form, name/address, advertising messages; maintaining mailing lists; maintaining and printing postage records; securing postage usage; buying postage electronically; retrieving user postage usage information; electronic keeping of time and date; updating of postage rates, ZIP+4 directory and mailing list; and having an integrated built-in ZIP+4 directory.