Device for recognition of firing of high pressure gas discharge lamp for car headlamp

摘要

The invention relates to an arrangement for detecting the ignition of a high-pressure gas discharge lamp, in particular for use in a vehicle headlight. Said arrangement contains a circuit for supplying the high-pressure gas discharge lamp with burning power, a control circuit and an ignition circuit. Said ignition circuit is acted upon, for ignition, by an auxiliary voltage. The control circuit is designed so that it detects ignition of the high-pressure gas discharge lamp immediately as a result of the behaviour or the status of the auxiliary voltage (UH). Said control circuit can be provided with a microcontroller (20). The auxiliary voltage supplied during ignition is connected to the microcontroller in such a manner that it detects ignition immediately. To this end, the auxiliary voltage is applied at the external interrupt entry (21) of the microcontroller by way of a voltage divider (22,23, 24) with logical potential. The falling edge which occurs during ignition as a result of the breakdown of the auxiliary voltage or the low voltage level is detected immediately by the microcontroller and interpreted as ignition.