Many of today’s modern alarm systems employ a moving coil loudspeaker as the siren element. To interface between the alarm system’s processing unit and the speaker, the usual circuits consist of a signal generation IC and a discrete ’H’-bridge.

The following note describes some of the features, benefits and applications of the FMMT617 NPN and FMMT717 PNP SOT23 transistors developed by Zetex.

LCD Backl ighting has generated widespread interest from many diverse disciplines within the engineering industry.

This note outlines the features, benefits and applications of the Zetex PNP SuperSOT series, plus some additional NPN applications, and follows on from application note AN11 which covered the low voltage variant NPN types FMMT618 and FMMT619.

At first sight the performance of the FMMT618 and FMMT619 transistors may appear unbelievable for SOT23 packaged devices, however the following note describes how this has been achieved.

The following note explains the popularity of relays as high current switches in automobiles, some of the problems to be solved in designing driver circuits, a standard driver circuit and an improved ZVN4206AV based circuit.

This application note gives some basic background information, examines the important parameters and specifications for the Zetex range of devices, and suggests a few application circuit examples.

This Application Note outlines the principle of avalanche mode operation, gives details on important parameter and operating conditions, and suggests a few application circuit examples.

DC-DC Converters are circuits designed to match loads to the power sources available. Generally, they accept power input at one voltage and supply one or more loads requiring power at different voltage levels.

The majority of modern printers use steppermotors and solenoids for driving the various transport and print mechanisms. These applications usually involve using drive signals directly from the control logic; and handling high-pulsed currents and voltages.