Half Bridge Controller and Driver for Industrial Linear Tubes

The MC33157 includes the oscillator circuit and two output channels to control a half–bridge power stage.

One of the channels is ground–referenced. The second one is floating to provide a bootstrap operation for the high side switch.

Dedicated Driver for Industrial Linear Tubes

•Main oscillator is current controlled, making it easy to set up by a single external resistor. On top of that, such a feature is useful to implement a dimming function by frequency shift.

•Filament pre–heating time control built–in.

•The strike sequence is controllable by external passive components, the resonnant frequency being independently adjustable. This frequency can be made different from the pre–heating and the steady state values. A frequency sweep between two defined values makes this IC suitable for any series resonnant topologies.

•Dedicated internal comparator provides an easy lamp strike detection implementation.

•Digital RESETpin provides a fast reset of the system (less than 10µs).

Both output MOSFET are set to “OFF” state when RESETis zero.

•Adjustable dead time makes the product suitable for any snubber capacitor and size of MOSFET used as power switches.

•Designed to be used with standard setting capacitors ≤470nF.

•A voltage reference, derived from the internal bandgap, is provided for external usage. This voltage is 100 trimmed at probe level yielding a 2 tolerance over the temperature range.