STK984-090A-E Gate Driver Voltage: High-side and low-side The high-side MOSFETs are driven with an internal charge pump. The gate voltage VG from the built-in charge pump circuit is set at VG=VB1+12V. Figure 8: Gate drive voltage variation with battery voltage for high-side MOSFETs The gate drive voltage for the low-side MOSFETs follows the voltage on VB1. If VB1 exceeds 18.5V, the gate drive voltage is limited to 17V. Figure 9: Gate drive voltage versus battery voltage for low-side MOSFETs www.onsemi.com 10