Combination of a laser and a controller for trimming a metallized dielectric film capacitor

Patent · Tue Aug 05 04:00:00 EDT 1986

OSTI ID:5401729

Lim, B Y

A combination of a laser system and a controller for use in vaporizing the material of a capacitor, which is formed from a pair of metallized dielectric films, to form a hole in order to trim the capacitance of the capacitator is described which consists of: a. a laser system including a laser modulator which turns the laser system on and off at a frequency rate of two hundred cycles per second; and b. a controller including a mechanical triggering device, a trigger/reset circuit which is electrically coupled to the mechanical triggering circuit and which provides a trigger signal in its triggered state and a reset signal in its untriggered state, a clock circuit which is electrically coupled to the trigger reset circuit and which provides clock signals in response to the trigger signal, a one-shot monostable, multivibrator circuit having an RC timing circuit which is electrically coupled to the clock circuit and to the laser modulator and which controls the pulse width of its output signal in a range of 0.005 seconds and 0.1 seconds in response to the clock signals, a counter which is electrically coupled to the one-shot monostable, multivibrator circuit and which counts each of the clock signals and a comparator which is electrically coupled to the counter in order to compare the number of the counted clock signals to a selected number and which is electrically coupled to the clock circuit. When the number of the counted clock signal equals the selected number, the comparator provides a clock inhibit signal in order to inhibit the clock circuit from providing any more clock signals.

• Assignee: NOV; EDB-86-159600; NOV-85-019572
• Patent Number(s): US 4604513
• OSTI ID: 5401729
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
420800 -- Engineering-- Electronic Circuits & Devices-- (-1989)
CAPACITANCE
CAPACITORS
COMPARATOR CIRCUITS
CONTROL SYSTEMS
DIELECTRIC MATERIALS
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELECTRONIC CIRCUITS
EQUIPMENT
EVAPORATION
FILMS
FREQUENCY MODULATION
HEATING
LASER-RADIATION HEATING
LASERS
MATERIALS
MODULATION
MULTIVIBRATORS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PLASMA HEATING
PULSE CIRCUITS
SIGNALS
TIMING CIRCUITS