SG3525A 13 VCC VC Q5 Q7 Q9 Q10 Q4 5.0k 11, 14 Vref Q8 Q11 Output Q6 2.0k Q1 Q2 Q3 Q6 Omitted in SG3527A 5.0k 10k 10k Clock F/F PWM Figure 9. Output Circuit (1/2 Circuit Shown) Q1 +V To Output Filter supply +Vsupply R1 R1 C1 R2 13 11 VC T1 A Q1 13 R2 VC 11 C2 A SG3525ASG3525A 14 14 B Q2 B GND R3 GND 12 12 For single-ended supplies, the driver outputs are grounded. In conventional push-pull bipolar designs, forward base drive is The VC terminal is switched to ground by the totem-pole controlled by R1-R3. Rapid turn-off times for the power devices source transistors on alternate oscillator cycles. are achieved with speed-up capacitors C1 and C2. Figure 10. Single−Ended SupplyFigure 11. Push−Pull Configuration +Vsupply +Vsupply R1 Q1 T1 C1 13 Q1 T1 11 13 T2 R1 V 11 C A VC A SG3525ASG3525A Q2 Q2 14 14 B B GND GND C2 R2 12 12 The low source impedance of the output drivers provides Low power transformers can be driven directly by the SG3525A. rapid charging of power FET input capacitance while Automatic reset occurs during deadtime, when both ends of the minimizing external components. primary winding are switched to ground. Figure 12. Driving Power FETSFigure 13. Driving Transformers in aHalf−Bridge Configurationwww.onsemi.comShare Feedback7 Your Opinion Matters