JAJSAH6H January 2006 – October 2017 LM3100
PRODUCTION DATA.
The LM3100 integrates an N-Channel buck (high-side) switch and associated floating high voltage gate driver. The gate drive circuit works in conjunction with an external bootstrap capacitor and an internal high voltage diode. A 33 nF capacitor (CBST) connected between BST and SW pins provides voltage to the high-side driver during the buck switch on-time. During each off-time, the SW pin falls to approximately –1 V and CBST charges from the VCC supply through the internal diode. The minimum off-time of 260 ns ensures adequate time each cycle to recharge the bootstrap capacitor.