초록 ▼

The invention relates to providing a reliable means for controlling a laser diode in an initiator for starting a pyrotechnic reaction in an ordnance. The circuit has an array of capacitors to tune the coupling of the input signal to provide for more efficient power transfer from an electrical energy

The invention relates to providing a reliable means for controlling a laser diode in an initiator for starting a pyrotechnic reaction in an ordnance. The circuit has an array of capacitors to tune the coupling of the input signal to provide for more efficient power transfer from an electrical energy system. The circuit contains a full wave rectifier to provide DC power to operate the circuit. The circuit also contains a two stage current amplifier that is controlled by a differential amplifier. The differential amplifier compares a voltage proportional to the current flowing through the controlled laser diode with a reference voltage. The differential amplifier controls the current amplifier to limit the current that can pass through the laser diode. The circuitry that provides the reference voltage has the ability to drive the reference voltage to zero when the input signal is removed or is too low to drive the circuit properly. This prohibits current spikes from developing in the laser diode when the circuit is shutting down. The reference voltage circuitry also turns the laser diode on relatively slowly to allow the current control circuitry to become stable. This prevents damaging current overshoots that otherwise could occur at the time the laser diode is turned on.

대표청구항 ▼

A driver circuit for defining a controlled current flowing through a device in response to one or more input signals, said driver circuit comprising: a reference voltage control circuit for generating a reference signal from one or more input signals, said reference signal being a function of said o

A driver circuit for defining a controlled current flowing through a device in response to one or more input signals, said driver circuit comprising: a reference voltage control circuit for generating a reference signal from one or more input signals, said reference signal being a function of said one or more input signals; a current detector for producing a sense signal proportional to the amplitude of said controlled current; a differential amplifier for comparing said reference signal with said sense signal to produce a control signal proportional to the difference between said reference signal and said sense signal; a current amplifier that generates said controlled current from said control signal; and circuit output terminals at which said controlled current can be applied to said device.