November 1993

8

Philips Semiconductors

Product specification

Control circuit for switched mode power supplies

TDA8380A

Figure 7 illustrates synchronization using a pulse transformer. Internal circuitry causes a DC shift which informs the

device that synchronization pulses are present (spikes around 0 V at the output of the pulse transformer) or not present

(DC 0 V at the output of the pulse transformer). When synchronization is not used the SYNC pin must be connected to

Fig.7 Synchronization using a pulse transformer.

Synchronization pulses present.

Synchronization pulses not present.