Patent application number | Description | Published |
20100017610 | Authentication system - An authentication system determines if a counterfeit ineligible unit is installed in a main device. When connected with a battery pack, a notebook PC generates and combines a random number and a function determination signal using a signal combining unit and transmits same to the battery pack. A first function calculation unit calculates the function of the random number. The battery pack has a signal separation unit to separate the combined signal into the random number and function determination signal, and a second function calculation unit to calculate the function of the random number for transmitting back to the notebook PC. A comparison unit compares the calculation results by the first and second function calculation units to determine whether the connected battery pack is an authorized one and denies connection if the pack is an unauthorized one. | 01-21-2010 |
20100017611 | Authentication system - An authentication system determines if a counterfeit ineligible unit is installed in a main device. When connected with a battery pack, a notebook PC generates and combines a random number and a function determination signal using a signal combining unit and transmits same to the battery pack. A first function calculation unit calculates the function of the random number. The battery pack has a signal separation unit to separate the combined signal into the random number and function determination signal, and a second function calculation unit to calculate the function of the random number for transmitting back to the notebook PC. A comparison unit compares the calculation results by the first and second function calculation units to determine whether the connected battery pack is an authorized one and denies connection if the pack is an unauthorized one. | 01-21-2010 |
20100024002 | Authentication system - An authentication system determines if a counterfeit ineligible unit is installed in a main device. When connected with a battery pack, a notebook PC generates and combines a random number and a function determination signal using a signal combining unit and transmits same to the battery pack. A first function calculation unit calculates the function of the random number. The battery pack has a signal separation unit to separate the combined signal into the random number and function determination signal, and a second function calculation unit to calculate the function of the random number for transmitting back to the notebook PC. A comparison unit compares the calculation results by the first and second function calculation units to determine whether the connected battery pack is an authorized one and denies connection if the pack is an unauthorized one. | 01-28-2010 |
Patent application number | Description | Published |
20090072908 | GAIN CONTROL CIRCUIT AND OPTICAL RECORDING AND REPRODUCING DEVICE USING THEREOF - A gain control circuit to determine gain by a current ratio of mutual conductance. The gain control circuit includes a first gain control circuit in which positive and negative phase input signals are supplied, gain is changed based on a first control signal, and positive and negative phase output signals are outputted, a second gain control circuit in which the positive and negative phase input signals are supplied, gain is changed based on a second control signal, and the positive and negative phase output signals are outputted, and a load circuit in which the positive phase output signal of the first gain control circuit and the negative phase output signal of the second gain control circuit are synthesized and supplied to a first input terminal, and the negative phase output signal of the first gain control circuit and the positive phase output signal of the second gain control circuit are synthesized and supplied to a second input terminal, and the synthesized signals are lead out through mutual conductance. | 03-19-2009 |
20100260219 | Laser drive - Disclosed herein is a laser driver including a light emission controlling section configured to stop generation of a control voltage by a control voltage generating section, causing a given voltage corresponding to a magnitude of a reference current to be outputted to an input node of a first emitter follower to operate the first emitter follower for a first time period from start of a light emission time period, release stop of the generation of the control voltage by the control voltage generating section, causing the control voltage to be outputted to the input node of the first emitter follower to operate the first emitter follower until end of the light emission time period of the laser, and operate a second emitter follower to discharge electric charges accumulated in the laser for a second time period after the end of the light emission time period of the laser. | 10-14-2010 |
20110075691 | Correction circuit, drive circuit, light emitting device, and method of correcting current pulse waveform - A correction circuit is provided, which may reduce dullness of a light output waveform due to wavelength detuning. The correction circuit includes an RC time constant circuit. The RC time constant circuit is used to correct a waveform of a current pulse outputted from a current source, the current source driving a surface-emitting semiconductor laser in a pulsed manner, so that a pulse waveform of light output of the semiconductor laser is approximately a rectangle. | 03-31-2011 |
20110241571 | Correction circuit, drive circuit, light-emitting device and correction method of current pulse waveform - A drive circuit and a drive current correcting method are described herein. The drive circuit comprises a current source that outputs a drive current, and a correction circuit that outputs a correction current. The correction circuit includes a first RC time constant circuit. An output terminal of the current source is connected to an output terminal of the correction circuit. | 10-06-2011 |
20120250713 | CORRECTION CIRCUIT, DRIVING CIRCUIT, LIGHT EMITTING APPARATUS, AND METHOD OF CORRECTING ELECTRIC CURRENT PULSE WAVEFORM - A correction circuit includes: a temperature rise derivation section which derives a temperature rise amount of a first channel of a multi-channel surface-emitting laser array due to the heating by at least one or a plurality of second channels adjacent to the first channel out of all channels included in the laser array; and a first correction section which corrects a waveform of an electric current pulse which is output from an electric current source capable of independently driving the laser array for each channel, to the first channel, based on the temperature rise amount derived by the temperature rise derivation section. | 10-04-2012 |
20140098832 | DRIVING DEVICE AND LIGHT-EMITTING UNIT - A driving device includes: a driving circuit configured to provide a drive current; a first detecting circuit; a second detecting circuit configured to detect a first reference current or a physical quantity corresponding thereto, as well as a second reference current or a physical quantity corresponding thereto; a first generating circuit configured to generate an additive voltage as a control voltage at a light-emission time of a light-emitting element, and further to generate a second voltage as a control voltage at a non-light-emission time of the light-emitting element; and a second generating circuit configured to generate a third reference current. The second detecting circuit has a first adder circuit that generates the first reference current by adding the second reference current and the third reference current with each other. | 04-10-2014 |
20140105234 | CORRECTION CIRCUIT, DRIVE CIRCUIT, LIGHT EMISSION UNIT, AND METHOD OF CORRECTING CURRENT PULSE WAVEFORM - A correction circuit includes a correction section configured to superpose a second current pulse on a first current pulse, and thereby correcting a waveform of the first current pulse, the first current pulse being output from a current source configured to drive a surface-emitting semiconductor laser in a pulsed manner, the correction section being configured to allow the second pulse to have a waveform obtained through attenuating a crest value of the second current pulse with time, increasing an initial crest value of the second current pulse by an amount that is larger as magnitude of the first current pulse is larger, and allowing the amount by which the initial crest value is increased to be smaller as ambient temperature of the semiconductor laser is higher, and being configured to output the second pulse having the waveform. | 04-17-2014 |
Patent application number | Description | Published |
20080309378 | SEMICONDUCTOR DEVICE - A semiconductor device | 12-18-2008 |
20090161813 | SEMICONDUCTOR DEVICE - In a semiconductor device including an N-line M-stage shift register circuit operated at high speed of, for example, several hundreds MHz. Input circuits input a common test pattern to each of pairs of shift registers in, for example, two lines out of the N lines. A plurality of outputs of the pairs of shift registers in the two lines are compared in comparators, and the comparison results are output. The N-line M-stage shift register circuit and the comparators are operated in synchronization with a clock signal at several hundreds MHz. Hence, even when the circuit scale (area) of the N-line M-stage shift register circuit is increased to involve apparent wiring delay, a defect in the shift register circuit can be detected at an actual speed. | 06-25-2009 |
20110307752 | SEMICONDUCTOR DEVICE, AND DESIGN METHOD, DESIGN TOOL, AND FAULT DETECTION METHOD OF SEMICONDUCTOR DEVICE - A bridging fault which has occurred between clock signal lines in a semiconductor device can be easily detected. A semiconductor device having a plurality of hold circuits and configured such that a scan test can be performed includes a first and a second clock signal lines supplied with normal operational clock signals having at least either frequencies or phases different from each other during normal operation, and a test clock signal controller which switches, during a test, between a state in which a first test clock signal, which is the same as that supplied to the first clock signal line, is supplied to the second clock signal line, and a state in which a second test clock signal, which is inverted or phase-shifted relative to the first test clock signal, is supplied to the second clock signal line. | 12-15-2011 |