摘要:
In an electrostatic micromotor, a mobile substrate faces a fixed substrate, and electrostatic-interaction elements are provided to allow a relative movement of the mobile substrate with respect to the fixed substrate in a direction of movement. The electrostatic-interaction elements include electrodes arranged on a facing surface of the fixed substrate (2) facing the mobile substrate. The mobile substrate has indentations, which extend within the mobile substrate starting from a respective facing surface that faces the fixed substrate and define between them projections staggered with respect to the electrodes in the direction of movement. Side walls of the indentations have a first distance of separation at the respective facing surface, and a second distance of separation, greater than the first distance of separation, at an internal region of the indentations.
摘要:
A power amplifier comprising at least a load element and at least an active element inserted, in series to each other, between a first and a second voltage reference is described. Advantageously, according to an embodiment of the invention, the load element comprises a DMOS transistor.
摘要:
The electronic device is formed in a die including a body of semiconductor material having a first face covered by a covering structure and a second face. An integral thermal spreader of metal is grown galvanically on the second face during the manufacture of a wafer, prior to cutting into dice. The covering structure comprises a passivation region and a protective region of opaque polyimide; the protective region and the passivation region are opened above the contact pads for the passage of leads.
摘要:
The manufacture process includes: forming a first wafer of semiconductor material housing integrated electronic components forming a microactuator control circuit and a signal preamplification circuit; forming microactuators, each including a rotor and a stator, in a surface portion of a second wafer of semiconductor material; attaching the second wafer to the first wafer, with the surface portion of the second wafer facing the first wafer; thinning the second wafer; attaching the second wafer to a third wafer to obtain a composite wafer; thinning the first wafer; cutting the composite wafer into a plurality of dice connected to a protection chip; removing the protection chip; attaching read/write transducers to the dice; and attaching the dice to supporting blocks for hard-disk drivers.
摘要:
An electromagnetic head for a storage device comprises a magnetic core forming a magnetic circuit, and a magnetoresistive means. The magnetic core is interrupted by an air-gap, thereby separating a first pole and second pole of the magnetic core. The magnetoresistive means is disposed in the region of the air-gap, and is connected to the magnetic core so as to be connected in the magnetic circuit.
摘要:
An anti-tampering circuit for a vehicle includes an operational circuit providing a predetermined function for the vehicle to be protected, and a control circuit connected to the operational circuit for enabling and disabling operation thereof. The control circuit includes a semiconductor substrate, a communications circuit formed on the semiconductor substrate receiving data corresponding to an identification code from at least one external source within the vehicle, and a non-volatile memory formed on the semiconductor substrate and connected to the communications circuit for storing only once a predetermined identification code. The communications circuit writes the received data to the non-volatile memory as the predetermined identification code when the control circuit is within the vehicle if the predetermined identification code has not already been stored therein. The control circuit further includes a comparator formed on the substrate for comparing the received data with the predetermined identification code and providing a comparison signal. A selector is also formed on the substrate for enabling and disabling the operational circuit responsive to the comparison signal.
摘要:
A wafer of semiconductor material for fabricating integrated devices, including a stack of superimposed layers including first and second monocrystalline silicon layers separated by an intermediate insulating layer made of a material selected from the group comprising silicon carbide, silicon nitride and ceramic materials. An oxide bond layer is provided between the intermediate layer and the second silicon layer. The wafer is fabricated by forming the intermediate insulating layer on the first silicon layer in a heated vacuum chamber; depositing the oxide layer; and superimposing the second silicon layer. When the stack of silicon, insulating material, oxide and silicon layers is heat treated, the oxide reacts so as to bond the insulating layer to the second silicon layer. As a ceramic material beryllium oxide, aluminium nitride, boron nitride and alumina may be used.
摘要:
A voltage regulator comprising a first power switch connected between the input terminal and output terminal; a storage condenser connected to the input terminal via a one-way switch; a second power switch connected between the condenser and the input terminal; and a regulating element connected to the output terminal and driving the power switches in such a manner as to maintain the output voltage constant. For better distributing electric and thermal stress and improving the reliability and working life of the regulator by reducing the interference caused by switching of the two power switches, a drive device is provided between the regulating element and the switches for detecting the input voltage and the voltage of the condenser, and keeping both switches on as long as the input voltage is above two given thresholds, turning off the second switch when the input voltage is higher than the condenser voltage and below the first threshold, and turning off the first switch when the input voltage is lower than the condenser voltage and below the second threshold.
摘要:
A series of Zener diodes (25) and an electronic power switch, such as an IGBT (18), are connected across a power supply. A circuit including a resistor (20) in series on the electronic switch, a threshold device (36, 38) connected to the resistor and a ramp generator with multiplier (40, 42, 44, 46, FIG. 2) or a thermal sensor (50, 44, 46 FIG. 3) detect the energy level dissipated in the electronic power switch when a transient occurs when the level exceeds a present value, the circuit supplies an output signal to a monostable circuit (26, 28, 48) to drive the electronic power switch with low resistance conditions for a preset time starting from the occurrence of the output signal. Another threshold device, connected to a resistor (30, 32), preferably senses the instantaneous power dissipated in the electronic switch to control the monostable circuit when the instantaneous power is higher than a preset threshold.
摘要:
This integrated semiconductor device aims at drastic reduction of the direct secondary breakdown phenomena and has a plurality of side-by-side elementary transistors forming an interdigited structure. To reduce the thermal interaction between the elementary transistors, the latter are spaced apart from one another by a distance approximately equal to the width of one elementary transistor and are driven by current sources. Spacing apart reduces electrothermal interaction. Further, in order to minimize the device area requirements, the space between any two adjacent elementary transistors is made to accommodate drive transistors operating as current sources, or the elementary transistors of the complementary stage where the device forms a class B output stage, the two output transistors whereof are alternatively switched on.