IMP560

IMP560

4

408-432-9100/www.impweb.com

© 2000 IMP, Inc.

Pin Descriptions

External Components

High–Voltages Present

Pin Number

Name

Function

Positive voltage supply for the IMP560. Inductor L may be connected here or to a

separate unregulated supply.

Boost converter storage capacitor. The voltage across the EL lamp is equal to twice the

Connection to flyback inductance, L.

5

GND

Ground pin.

EL lamp drive. (See above)

The EL lamp oscillator frequency setting pin. The oscillator frequency is controlled

External Component

Description and Selection Guide

Diode

A fast reverse recovery diode, with BV > 100, such as a 1N4148.

This is the high voltage capacitor that stores the inductive energy transferred through the

diode. A 100 volt capacitor between 10nF and 100nF is recommended.

The EL lamp oscillator frequency setting resistor. This resistor, connected between the

Lamp color is also determined by this frequency. A 2M

Ω resistor will give ≈700Hz.

Switching Oscillator frequency setting resistor. The switching oscillator resistor is connected

to the resistor value, dropping as the resistance increases.

Inductor L

The inductor provides the voltage boost needed by means of inductive “flyback”. The internal

MOSFET switch alternately opens and closes the ground connection for the inductor at the

Smaller inductors are preferred to prevent saturation. As the value of the inductor

increases (and the series DC resistance of the inductor decreases), the switching frequency

can handle more current are more desirable when larger area EL lamps must be driven.

The IMP560 generates high voltages and caution should

be exercised.