Abstract: A dc-to-ac inverter employing a control low power section and a power section. The low power section comprises a square wave generator, cross-coupled NOR latches and low level transistor switches for providing switching current to the power section. The power section employs complementary FET drivers and power switches connected to a battery or other source of dc and a ferro-resonant transformer for changing dc to ac.The power section is protected by a voltage sensor. In a preferred embodiment, this voltage is proportional to the current through the respective power switches and is used to unlatch the applicable NOR latch, thereby causing shut off of the protected network of the power section.

Abstract: A battery charger with an SCR providing high charging current to a battery until a predetermined high voltage level is sensed. When the voltage sensed reduces to a float voltage minimum level, a trickle charge current is supplied through another SCR until a float voltage maximum level is sensed, which suspends trickle charge current until the voltage again reduces to the float voltage minimum level. When a load reduces the battery voltage so that the sensed voltage is reduced to a predetermined low level below the float voltage minimum level, then the high charging current SCR is again gated on to charge the battery.